New technologies in surgery

MINIMALLY INVASIVE SURGERY: INTRODUCTION

Minimally-invasive surgery describes an area of surgery that crosses all traditional disciplines, from general surgery to neurosurgery. It is not a discipline unto itself, but more a philosophy of surgery, a way of thinking. Minimally-invasive surgery is a means of performing major operations through small incisions, often using miniaturized, high-tech imaging systems, to minimize the trauma of surgical exposure. Some believe that minimal access surgery more accurately describes the small incisions generally necessary to gain access to surgical sites in high-tech surgery, but John Wickham’s term minimally-invasive surgery (MIS) is widely used because it describes the paradox of postmodern high-tech surgery—small holes, big operations—and the “minimalness” of the access and invasiveness of the procedures, captured in three words.

Historical Background

While the term minimally-invasive surgery is relatively recent, the history of its component parts is nearly 100 years old. What is considered the newest and most popular variety of MIS, laparoscopy, is in fact the oldest. Primitive laparoscopy, placing a cystoscope within an inflated abdomen, was first performed by Kelling in 1901. 1 Illumination of the abdomen required hot elements at the tip of the scope and was dangerous. In the late 1950s Hopkins described the rod lens, a method of transmitting light through a solid quartz rod with no heat and little light loss. 1 Around the same time, thin quartz fibers were discovered to be capable of trapping light internally and conducting it around corners, opening the field of fiberoptics and allowing the rapid development of flexible endoscopes. 2,3 In the 1970s the application of flexible endoscopy grew faster than that of rigid endoscopy except in a few fields such as gynecology and orthopedics. 4 By the mid-1970s rigid and flexible endoscopes made a rapid transition from diagnostic instruments to therapeutic ones. The explosion of video-assisted surgery in the past 10 years was a result of the development of compact, high-resolution charge-coupled devices which could be mounted on the internal end of flexible endoscopes or on the external end of a Hopkins telescope. Coupled with bright light sources, fiberoptic cables, and high-resolution video monitors, the videoendoscope has changed our understanding of surgical anatomy and reshaped surgical practice.

While optical imaging produced the majority of MIS procedures, other (traditionally radiologic) imaging technologies allowed the development of innovative procedures in the 1970s. Fluoroscopic imaging allowed the adoption of percutaneous vascular procedures, the most revolutionary of which was balloon angioplasty. Balloon-based procedures spread into all fields of medicine, assisting in a minimally-invasive manner to open up clogged lumens. Stents were then developed that were used in many disciplines to keep the newly ballooned segment open. The culmination of fluoroscopic balloon and stent proficiency is exemplified by the transvenous intrahepatic portosystemic shunt (TIPS) (FIG. 1).

MIS procedures using ultrasound imaging have been limited to fairly crude exercises, such as fragmenting kidney stones and freezing liver tumors, because of the relatively low resolution of ultrasound devices. Newer, high-resolution ultrasound methods with high-frequency crystals may act as a guide while performing minimally-invasive resections of individual layers of the intestinal wall.

FIG. 1.

With the transvenous intrahepatic portosystemic shunt (TIPS), percutaneous access to the superior vena cava is followed by the retrograde cannulation of the hepatic veins. Next a needle is advanced through the hepatic parenchyma until the portal venous radicle is located. A guidewire is passed across this connection, and after dilation a metallic stent is expanded with a balloon. While not often performed by surgeons, TIPS represents a particularly creative example of minimally-invasive surgery. (Reproduced with permission from Hunter JG, Sackier JM (eds): Minimally-Invasive Surgery. New York: McGraw-Hill, 1993, p 271.)

Axial imaging, such as computed tomography (CT), has allowed the development of an area of MIS that is not often recognized because it requires only a CT scanner and a long needle. CT-guided drainage of abdominal fluid collections and percutaneous biopsy of abnormal tissues are minimally-invasive means of performing procedures that previously required a celiotomy. Recently, CT-guided percutaneous radiofrequency ablation has emerged as a useful treatment for primary and metastatic liver tumors. This procedure has also been performed laparoscopically under ultrasound guidance. 5

A powerful, noninvasive method of imaging that will allow the development of the least invasive—and potentially noninvasive—surgery is magnetic resonance imaging (MRI).

MRI is an extremely valuable diagnostic tool, but it is only slowly coming to be of therapeutic value. One obstacle to the use of MRI for MIS is that image production and refreshment of the image as a procedure progresses are slow. Another is that all instrumentation must be nonmetallic when working with the powerful magnets of an MRI scanner. Moreover, MRI magnets are bulky and limit the surgeon’s access to the patient. Open magnets have been developed that allow the surgeon to stand between two large MRI coils, obtaining access to the portion of the patient being scanned. The advantage of MRI, in addition to the superb images produced, is that there is no radiation exposure to patient or surgeon. Some neurosurgeons are accumulating experience using MRI to perform frameless stereotactic surgery.

The Minimally-Invasive Team

From the beginning, the tremendous success of minimally-invasive surgery has been founded on the understanding that a team approach is necessary. The numerous laparoscopic procedures range from basic to advanced complexity, and require that the surgical team have an intimate understanding of the operative conduct (Table 13-1). Minimally-invasive procedures require complicated and fragile equipment that demands constant maintenance. In addition, multiple intraoperative adjustments to the equipment, camera, insufflator, monitors, and patient/surgeon position are made during these procedures. As such, a coordinated team approach is mandated in order to ensure patient safety and excellent outcomes.

A typical MIS team may consist of a laparoscopic surgeon and an operating room nurse with an interest in laparoscopic surgery. Adding dedicated laparoscopic assistants and circulating staff with an intimate knowledge of the equipment will add to and enhance the team nucleus. Studies have demonstrated that having a designated laparoscopic team reduces the conversion rate and overall operative time, which is translated into a cost savings for patient and hospital. 6

Physiology

Even with the least invasive of the MIS procedures, physiologic changes occur. Many minimally-invasive procedures require minimal or no sedation, and there are few alterations to the cardiovascular, endocrinologic, or immunologic systems. The least invasive of such procedures include stereotactic biopsy of breast lesions and flexible gastrointestinal endoscopy. Minimally-invasive procedures that require general anesthesia have a greater physiologic impact because of the anesthetic agent, the incision (even if small), and the induced pneumoperitoneum.

Laparoscopy

The unique feature of endoscopic surgery in the peritoneal cavity is the need to lift the abdominal wall from the abdominal organs. Two methods have been devised for achieving this. 7 The first, used by most surgeons, is the induction of a pneumoperitoneum. Throughout the early twentieth century intraperitoneal visualization was achieved by inflating the abdominal cavity with air, using a sphygmomanometer bulb. 8 The problem with using air insufflation is that nitrogen is poorly soluble in blood and is slowly absorbed across the peritoneal surfaces. Air pneumoperitoneum was believed to be more painful thaitrous oxide pneumoperitoneum but less painful than carbon dioxide pneumoperitoneum. Subsequently, carbon dioxide and nitrous oxide were used for inflating the abdomen. N2O had the advantage of being physiologically inert and rapidly absorbed. It also provided better analgesia for laparoscopy performed under local anesthesia when compared with CO2 or air. 9 Despite initial concerns that N2O would not suppress combustion, controlled clinical trials have established its safety within the peritoneal cavity. 10 In addition, nitrous oxide has recently been shown to reduce the intraoperative end-tidal CO2 and minute ventilation required to maintain homeostasis when compared to CO2 pneumoperitoneum. 10 The effect of N2O on tumor biology and the development of port site metastasis are unknown. As such, caution should be exercised when performing laparoscopic cancer surgery with this agent. Finally, the safety of N2O pneumoperitoneum in pregnancy has yet to be elucidated.

The physiologic effects of CO2 pneumoperitoneum can be divided into two areas: (1) gas-specific effects and (2) pressure-specific effects (FIG. 2). CO2 is rapidly absorbed across the peritoneal membrane into the circulation. In the circulation, CO2 creates a respiratory acidosis by the generation of carbonic acid. 11 Body buffers, the largest reserve of which lies in bone, absorb CO2 (up to 120 L) and minimize the development of hypercarbia or respiratory acidosis during brief endoscopic procedures. 11 Once the body buffers are saturated, respiratory acidosis develops rapidly, and the respiratory system assumes the burden of keeping up with the absorption of CO2 and its release from these buffers.

FIG. 2.

Carbon dioxide gas insufflated into the peritoneal cavity has both local and systemic effects that cause a complex set of hemodynamic and metabolic alterations. [Reproduced with permission from Hunter JG (ed): Baillière’s Clinical Gastroenterology Laparoscopic Surgery. London/Philadelphia: Baillière Tindall, 1993, p 758.]

In patients with normal respiratory function this is not difficult; the anesthesiologist increases the ventilatory rate or vital capacity on the ventilator. If the respiratory rate required exceeds 20 breaths per minute, there may be less efficient gas exchange and increasing hypercarbia. 12 Conversely, if vital capacity is increased substantially, there is a greater opportunity for barotrauma and greater respiratory motion–induced disruption of the upper abdominal operative field. In some situations it is advisable to evacuate the pneumoperitoneum or reduce the intra-abdominal pressure to allow time for the anesthesiologist to adjust for hypercarbia. 13 While mild respiratory acidosis probably is an insignificant problem, more severe respiratory acidosis leading to cardiac arrhythmias has been reported. 14 Hypercarbia also causes tachycardia and increased systemic vascular resistance, which elevates blood pressure and increases myocardial oxygen demand. 11,14

The pressure effects of the pneumoperitoneum on cardiovascular physiology also have been studied. In the hypovolemic individual, excessive pressure on the inferior vena cava and a reverse Trendelenburg position with loss of lower extremity muscle tone may cause decreased venous return and cardiac output. 11,15 This is not seen in the normovolemic patient. The most common arrhythmia created by laparoscopy is bradycardia. A rapid stretch of the peritoneal membrane often causes a vagovagal response with bradycardia and occasionally hypotension. 16 The appropriate management of this event is desufflation of the abdomen, administration of vagolytic agents (e.g., atropine), and adequate volume replacement. 17

With the increased intra-abdominal pressure compressing the inferior vena cava, there is diminished venous return from the lower extremities. This has been well documented in the patient placed in the reverse Trendelenburg position for upper abdominal operations. Venous engorgement and decreased venous return promote venous thrombosis. 18,19 Many series of advanced laparoscopic procedures in which deep venous thrombosis (DVT) prophylaxis was not used demonstrate the frequency of pulmonary embolus. This usually is an avoidable complication with the use of sequential compression stockings, subcutaneous heparin, or low-molecular-weight heparin. 20 In short-duration laparoscopic procedures, such as appendectomy, hernia repair, or cholecystectomy, the risk of DVT may not be sufficient to warrant extensive DVT prophylaxis.

The increased pressure of the pneumoperitoneum is transmitted directly across the paralyzed diaphragm to the thoracic cavity, creating increased central venous pressure and increased filling pressures of the right and left sides of the heart. If the intra-abdominal pressures are kept under 20 mm Hg, the cardiac output usually is well maintained. 19,20,21 The direct effect of the pneumoperitoneum on increasing intrathoracic pressure increases peak inspiratory pressure, pressure across the chest wall, and also the likelihood of barotrauma. Despite these concerns, disruption of blebs and consequent pneumothoraces are rare after uncomplicated laparoscopic surgery. 21

Increased intra-abdominal pressure decreases renal blood flow, glomerular filtration rate, and urine output. These effects may be mediated by direct pressure on the kidney and the renal vein. 22,23 The secondary effect of decreased renal blood flow is to increase plasma renin release, thereby increasing sodium retention. Increased circulating antidiuretic hormone (ADH) levels also are found during the pneumoperitoneum, increasing free water reabsorption in the distal tubules. 24 Although the effects of the pneumoperitoneum on renal blood flow are immediately reversible, the hormonally mediated changes, such as elevated ADH levels, decrease urine output for up to 1 hour after the procedure has ended. Intraoperative oliguria is common during laparoscopy, but the urine output is not a reflection of intravascular volume status; intravenous fluid administration during an uncomplicated laparoscopic procedure should not be linked to urine output. Because fluid losses through the open abdomen are eliminated with laparoscopy, the need for supplemental fluid during a laparoscopic surgical procedure is rare.

The hemodynamic and metabolic consequences of pneumoperitoneum are well tolerated by healthy individuals for a prolonged period and by most individuals for at least a short period. Difficulties can occur when a patient with compromised cardiovascular function is subjected to a long laparoscopic procedure. It is during these procedures that alternative approaches should be considered or insufflation pressure reduced. Alternative gases that have been suggested for laparoscopy include the inert gases helium, neon, and argon. These gases are appealing because they cause no metabolic effects, but are poorly soluble in blood (unlike CO2 and N2O) and are prone to create gas emboli if the gas has direct access to the venous system. 19 Gas emboli are rare but serious complications of laparoscopic surgery. 20,25 They should be suspected if hypotension develops during insufflation. Diagnosis may be made by listening (with an esophageal stethoscope) for the characteristic “mill wheel” murmur. The treatment of gas embolism is to place the patient in a left lateral decubitus position with the head down to trap the gas in the apex of the right ventricle. 20 A rapidly placed central venous catheter then can be used to aspirate the gas out of the right ventricle.

In some situations minimally-invasive abdominal surgery should be performed without insufflation. This has led to the development of an abdominal lift device that can be placed through a 10- to 12-mm trocar at the umbilicus. 26 These devices have the advantage of creating little physiologic derangement, but they are bulky and intrusive. The exposure and working room offered by lift devices also are inferior to those accomplished by pneumoperitoneum. Lifting the anterior abdominal wall causes a “pinching in” of the lateral flank walls, displacing the bowel medially and anteriorly into the operative field. A pneumoperitoneum, with its well-distributed intra-abdominal pressure, provides better exposure. Abdominal lift devices also cause more postoperative pain, but they do allow the performance of MIS with standard (nonlaparoscopic) surgical instruments.

Early it was predicted that the surgical stress response would be significantly lessened with laparoscopic surgery, but this is not always the case. Serum cortisol levels after laparoscopic operations are often higher than after the equivalent operation performed through an open incision. 27 In terms of endocrine balance, the greatest difference between open and laparoscopic surgery is the more rapid equilibration of most stress-mediated hormone levels after laparoscopic surgery. Immune suppression also is less after laparoscopy than after open surgery. There is a trend toward more rapid normalization of cytokine levels after a laparoscopic procedure than after the equivalent procedure performed by celiotomy. 28

Transhiatal mobilization of the thoracic esophagus is commonly performed as a component of many laparoscopic upper abdominal procedures. Entering the posterior mediastinum transhiatally exposes the thoracic organs to positive insufflation pressure and may result in decreased venous return and a resultant decrease in cardiac output. If there is compromise of the mediastinal pleura with resultant CO₂ pneumothorax, the defect should be enlarged so as to prevent a tension pneumothorax.

Thoracoscopy

The physiology of thoracic MIS (thoracoscopy) is different from that of laparoscopy. Because of the bony confines of the thorax it is unnecessary to use positive pressure when working in the thorax. 29 The disadvantages of positive pressure in the chest include decreased venous return, mediastinal shift, and the need to keep a firm seal at all trocar sites. Without positive pressure, it is necessary to place a double-lumen endotracheal tube so that the ipsilateral lung can be deflated when the operation starts. By collapsing the ipsilateral lung, working space within the thorax is obtained. Because insufflation is unnecessary in thoracoscopic surgery, it can be beneficial to utilize standard instruments via extended port sites in conjunction with thoracoscopic instruments. This approach is particularly useful when performing advanced procedures such as thoracoscopic anatomic pulmonary resection.

Extracavitary Minimally-Invasive Surgery

Many new MIS procedures are creating working spaces in extrathoracic and extraperitoneal locations. Laparoscopic inguinal hernia repair usually is performed in the anterior extraperitoneal Retzius space. 30,31 Laparoscopic nephrectomy often is performed with retroperitoneal laparoscopy. Recently, an endoscopic retroperitoneal approach to pancreatic necrosectomy has been introduced. 32 Lower extremity vascular procedures and plastic surgical endoscopic procedures require the development of working space in unconventional planes, often at the level of the fascia, sometimes below the fascia, and occasionally ionanatomic regions. 33 Some of these techniques use insufflation of gas, but many use balloon inflation to develop the space, followed by low-pressure gas insufflation or lift devices to maintain the space (FIG. 3). These techniques produce fewer and less severe adverse physiologic consequences than does the pneumoperitoneum, but the insufflation of gas into extraperitoneal locations can spread widely, causing subcutaneous emphysema and metabolic acidosis.

FIG. 3.

Balloons are used to create extra-anatomic working spaces. In this example a balloon is introduced into the space between the posterior rectus sheath and the rectus abdominis muscle. The balloon is inflated in the preperitoneal space to create working room for extraperitoneal endoscopic hernia repair.

Anesthesia

The most important factors in appropriate anesthesia management are related to CO₂ pneumoperitoneum. 17 The laparoscopic surgeon can influence cardiovascular performance by releasing intra-abdominal retraction and dropping the pneumoperitoneum. Insensible fluid losses are negligible, and therefore intravenous fluid administration should not exceed a maintenance rate. MIS procedures usually are outpatient procedures, and short-acting anesthetic agents are preferable. Because the factors that require hospitalization after laparoscopic procedures include the management of nausea, pain, and urinary retention, the anesthesiologist should minimize the use of agents that provoke these conditions and maximize the use of medications that prevent such problems. Critical to the anesthesia management of these patients is the use of nonnarcotic analgesics (e.g., ketorolac) and the liberal use of antiemetic agents.

General Principles of Access and Equipment

The most natural ports of access for MIS are the anatomic portals of entry and exit. The nares, mouth, urethra, and anus are used to access the respiratory, gastrointestinal, and urinary systems. The advantage of using these points of access is that no incision is required. The disadvantages lie in the long distances between the orifice and the region of interest.

Access to the vascular system may be accomplished under local anesthesia by cutting down and exposing the desired vessel, usually in the groin. Increasingly, vascular access is obtained with percutaneous techniques using a small incision, a needle, and a guidewire, over which are passed a variety of different sized access devices. This approach, known as the Seldinger technique, is most frequently used by general surgeons for placement of Hickman catheters, but also is used to gain access to the arterial and venous system for performance of minimally-invasive procedures. Guidewire-assisted, Seldinger-type techniques also are helpful for gaining access to the gut for procedures such as percutaneous endoscopic gastrostomy, for gaining access to the biliary system through the liver, and for gaining access to the upper urinary tract.

In thoracoscopic surgery, the access technique is similar to that used for placement of a chest tube. In these procedures general anesthesia and split-lung ventilation are essential. A small incision is made over the top of a rib and, under direct vision, carried down through the pleura. The lung is collapsed, and a trocar is inserted across the chest wall to allow access with a telescope. Once the lung is completely collapsed, subsequent access may be obtained with direct puncture, viewing all entry sites through the videoendoscope. Because insufflation of the chest is unnecessary, simple ports that keep the small incisions open are all that is required to allow repeated access to the thorax.

Laparoscopic Access

The requirements for laparoscopy are more involved, because the creation of a pneumoperitoneum requires that instruments of access (trocars) contain valves to maintain abdominal inflation.

Two methods are used for establishing abdominal access during laparoscopic procedures. 34,35 The first, direct puncture laparoscopy, begins with the elevation of the relaxed abdominal wall with two towel clips or a well-placed hand. A small incision is made in the umbilicus, and a specialized spring-loaded (Veress) needle is placed in the abdominal cavity (FIG. 4A and B). With the Veress needle, two distinct pops are felt as the surgeon passes the needle through the abdominal wall fascia and the peritoneum. The umbilicus usually is selected as the preferred point of access because in this location the abdominal wall is quite thin, even in obese patients. The abdomen is inflated with a pressure-limited insufflator. CO2 gas is usually used, with maximal pressures in the range of 14 to 15 mm Hg. During the process of insufflation it is essential that the surgeon observe the pressure and flow readings on the monitor to confirm an intraperitoneal location of the Veress needle tip (FIG. 5). Laparoscopic surgery can be performed under local anesthesia, but general anesthesia is preferable. Under local anesthesia, N2O is used as the insufflating agent, and insufflation is stopped after 2 L of gas is insufflated or when a pressure of 10 mm Hg is reached.

FIG. 4.

A. Insufflation of the abdomen is accomplished with a Veress needle held at its serrated collar with a thumb and forefinger. B. Because linea alba is fused to the umbilicus, the abdominal wall is grasped with fingers or penetrating towel clip in order to elevate the abdominal wall away from the underlying structures.

It is essential to be able to interpret the insufflator pressure readings and flow rates. These readings indicate proper intraperitoneal placement of the Veress needle.

After peritoneal insufflation, direct access to the abdomen is obtained with a 5- or 10-mm trocar. The critical issues for safe direct-puncture laparoscopy include the use of a vented stylet for the trocar, or a trocar with a safety shield or dilating tip. The trocar must be pointed away from the sacral promontory and the great vessels. 36 Patient position should be surveyed prior to trocar placement to ensure a proper trajectory. For performance of laparoscopic cholecystectomy, the trocar is angled toward the right upper quadrant.

Occasionally the direct peritoneal access (Hasson) technique is advisable. 37 With this technique, the surgeon makes a small incision just below the umbilicus and under direct vision locates the abdominal fascia. Two Kocher clamps are placed on the fascia, and with a curved Mayo scissors a small incision is made through the fascia and underlying peritoneum. A finger is placed into the abdomen to make sure that there is no adherent bowel. A sturdy suture is placed on each side of the fascia and secured to the wings of a specialized trocar, which is then passed directly into the abdominal cavity (FIG. 6). Rapid insufflation can make up for some of the time lost with the initial dissection. This technique is preferable for the abdomen of patients who have undergone previous operations in which small bowel may be adherent to the undersurface of the abdominal wound. The close adherence of bowel to the peritoneum in the previously operated abdomen does not eliminate the possibility of intestinal injury, but should make great vessel injury extremely unlikely. Because of the difficulties in visualizing the abdominal region immediately adjacent to the primary trocar, it is recommended that the telescope be passed through a secondary trocar in order to inspect the site of initial abdominal access. 35 Secondary punctures are made with 5- and 10-mm trocars. For safe access to the abdominal cavity, it is critical to visualize all sites of trocar entry. 35,36 At the completion of the operation, all trocars are removed under direct vision and the insertion sites are inspected for bleeding. If bleeding occurs, direct pressure with an instrument from another trocar site or balloon tamponade with a Foley catheter placed through the trocar site generally stops the bleeding within 3 to 5 minutes. When this is not successful, a full-thickness abdominal wall suture has been used successfully to tamponade trocar site bleeding.

FIG. 6.

The open laparoscopy technique involves identification and incision of the peritoneum, followed by the placement of a specialized trocar with a conical sleeve to maintain a gas seal. Specialized wings on the trocar are attached to sutures placed through the fascia to prevent loss of the gas seal.

It is generally agreed that 5-mm trocars need no site suturing. Ten-millimeter trocars placed off the midline and above the transverse mesocolon do not require repair. Conversely, if the fascia has been dilated to allow the passage of the gallbladder, all midline 10-mm trocar sites should be repaired at the fascial level with interrupted sutures. Specialized suture delivery systems similar to crochet needles have been developed for mass closure of the abdominal wall in obese patients, in whom it is difficult to visualize the fascia through a small skin incision. Failure to close lower abdominal trocar sites that are 10 mm in diameter or larger can lead to an incarcerated hernia.

Access for Subcutaneous and Extraperitoneal Surgery

There are two methods for gaining access to nonanatomic spaces. For retroperitoneal locations, balloon dissection is effective. This access technique is appropriate for the extraperitoneal repair of inguinal hernias and for retroperitoneal surgery for adrenalectomy, nephrectomy, lumbar discectomy, pancreatic necrosectomy, or para-aortic lymph node dissection. 38,39 The initial access to the extraperitoneal space is performed in a way similar to direct puncture laparoscopy, except that the last layer (the peritoneum) is not traversed. Once the transversalis fascia has been punctured, a specialized trocar with a balloon on the end is introduced. The balloon is inflated in the extraperitoneal space to create a working chamber. The balloon then is deflated and a Hasson trocar is placed. An insufflation pressure of 10 mm Hg usually is adequate to keep the extraperitoneal space open for dissection and will limit subcutaneous emphysema. Higher gas pressures force CO2 into the soft tissues and may contribute to hypercarbia. Extraperitoneal endosurgery provides less working space than laparoscopy, but eliminates the possibility of intestinal injury, intestinal adhesion, herniation at the trocar sites, and ileus. These issues are important for laparoscopic hernia repair because extraperitoneal approaches prevent the small bowel from sticking to the prosthetic mesh. 31

Subcutaneous surgery, the newest method of access in minimally-invasive surgery, uses the creation of working room in nonanatomic spaces. This technique has been most widely used in cardiac, vascular, and plastic surgery. 33 In cardiac surgery, subcutaneous access has been used for saphenous vein harvesting, and in vascular surgery for ligation of subfascial perforating veins (Linton procedure). With minimally-invasive techniques the entire saphenous vein above the knee may be harvested through a single incision 40,41 (FIG. 7). Once the saphenous vein is located, a long retractor that holds a 5-mm laparoscope allows the coaxial dissection of the vein and coagulation or clipping of each side branch. A small incision above the knee also can be used to ligate perforating veins in the lower leg.

Subcutaneous access is also used for plastic surgical procedures. 41 Minimally-invasive approaches are especially well suited to cosmetic surgery, in which attempts are made to hide the incision. It is easier to hide several 5-mm incisions than one long incision. The technique of blunt dissection along fascial planes combined with lighted retractors and endoscope-holding retractors is most successful for extensive subcutaneous surgery. Some prefer gas insufflation of these soft tissue planes. The primary disadvantage of soft tissue insufflation is that subcutaneous emphysema can be created.

Hand-Assisted Laparoscopic Access

Hand-assisted laparoscopic surgery (HALS) is thought to combine the tactile advantages of open surgery with the minimal access of laparoscopy and thoracoscopy. This approach is commonly used to assist with difficult cases before conversion to celiotomy is necessary. Additionally, HALS is employed to help surgeons negotiate the steep learning curve associated with advanced laparoscopic procedures. 42 This technology employs a “port” for the hand which preserves the pneumoperitoneum and enables endoscopic visualization in combination with the use of minimally-invasive instruments (FIG. 8). Formal investigation of this modality has been limited primarily to case reports and small series, and has focused primarily on solid organ and colon surgery.

FIG. 8.

This is an example of hand-assisted laparoscopic surgery during left colectomy. The surgeon uses a hand to provide retraction and counter tension during mobilization of the colon from its retroperitoneal attachments, as well as during division of the mesocolon. This technique is particularly useful in the region of the transverse colon.

Port Placement

Trocars for the surgeon’s left and right hand should be placed at least 10 cm apart. For most operations it is possible to orient the telescope between these two trocars and slightly retract from them. The ideal trocar orientation creates an equilateral triangle between the surgeon’s right hand, left hand, and the telescope, with 10 to 15 cm on each leg. If one imagines the target of the operation (e.g., the gallbladder or gastroesophageal junction) oriented at the apex of a second equilateral triangle built on the first, these four points of reference create a diamond (FIG. 9). The surgeon stands behind the telescope, which provides optimal ergonomic orientation but frequently requires that a camera operator (or robotic arm) reach between the surgeon’s hands to guide the telescope.

FIG. 9.

The diamond configuration created by placing the telescope between the left and the right hand, recessed from the target by about 15 cm. The distance between the left and the right hand is also ideally 10 to 15 cm. In this “baseball diamond” configuration, the surgical target occupies the second base position.

The position of the operating table should permit the surgeon to work with both elbows in at the sides, with arms bent 90° at the elbow. 43 It usually is necessary to alter the operating table position with left or right tilt with the patient in the Trendelenburg or reverse Trendelenburg position, depending on the operative field. 44,45

Imaging Systems

Two methods of videoendoscopic imaging are widely used. Both methods use a camera with a charge-coupled device (CCD), which is an array of photosensitive sensor elements (pixels) that convert the incoming light intensity to an electric charge. The electric charge is subsequently converted into a black-and-white image. 46 The first of these is flexible videoendoscopy, where the CCD camera is placed on the internal end of a long, flexible endoscope. In the second method, thin quartz fibers are packed together in a bundle, and the CCD camera is mounted on the external end of the endoscope. Most standard gastrointestinal endoscopes have the CCD chip at the distal end, but small, delicate choledochoscopes and nephroscopes are equipped with fiberoptic bundles. 47 Distally-mounted CCD chips were developed for laparoscopy, but are unpopular.

Video cameras come in two basic designs. The one-chip camera has a black-and-white video chip that has an internal processor capable of converting gray scales to approximate colors. Perfect color representation is not possible with a one-chip camera, but perfect color representation is rarely necessary for endosurgery. The most accurate color representation is obtained using a three-chip video camera. A three-chip camera has red, green, and blue (RGB) input, and is identical to the color cameras used for television production. 46 RGB imaging provides the highest fidelity, but is probably not necessary for everyday use. An additional feature of newer video cameras is digital enhancement. Digital enhancement detects edges, areas where there are drastic color or light changes between two adjacent pixels. 48 By enhancing this difference, the image appears sharper and surgical resolution is improved. Digital enhancement is available on one- and three-chip cameras. Priorities in a video system for MIS are illumination first, resolution second, and color third. Without the first two attributes, video surgery is unsafe. Imaging for laparoscopy, thoracoscopy, and subcutaneous surgery uses a rigid metal telescope, usually 30 cm in length. This telescope contains a series of quartz optical rods with differing optical characteristics that provide a specific character to each telescope. 49 These metal telescopes vary in size from 2 to 10 mm in diameter. Since light transmission is dependent on the cross-sectional area of the quartz rod, when the diameter of a rod/lens system is doubled, the illumination is quadrupled. Little illumination is needed in highly-reflective, small spaces such as the knee, and a very small telescope will suffice. When working in the abdominal cavity, especially if blood is present, the full illumination of a 10-mm telescope usually is necessary.

Rigid telescopes may have a flat or angled end. The flat end provides a straight view (0°), and the angled end provides an oblique view (30 or 45°). 46 Angled scopes allow greater flexibility in viewing a wider operative field through a single trocar site (FIG. 10); rotating an angled telescope changes the field of view. The use of an angled telescope has distinct advantages for most videoendoscopic procedures, particularly in visualizing the common bile duct during laparoscopic cholecystectomy or visualizing the posterior esophagus or the tip of the spleen during laparoscopic fundoplication.

FIG. 10.

The laparoscope tips come in a variety of angled configurations. All laparoscopes have a 70° field of view. A 30° angled scope enables the surgeon to view this field at a 30° angle to the long axis of the scope.

Light is delivered to the endoscope through a fiberoptic light cable. These light cables are highly inefficient, losing more than 90% of the light delivered from the light source. Extremely bright light sources (300 watts) are necessary to provide adequate illumination for video endosurgery.

The quality of the videoendoscopic image is only as good as the weakest component in the imaging chain (FIG. 11). Therefore it is important to use a video monitor that has a resolution equal to or greater than the camera being used. 49  Resolution is the ability of the optical system to distinguish between line pairs. The larger the number of line pairs per millimeter, the sharper and more detailed the image. Most high-resolution monitors have up to 700 horizontal lines. High definition television (HDTV) can deliver up to eight times more resolution than the standard NTSC/PAL monitors; when combined with digital enhancement, a very sharp and well-defined image can be achieved. 46,49 A heads-up display (HUD) is a high-resolution liquid crystal monitor that is built into eyewear worn by the surgeon. 50 This technology allows the surgeon to view the endoscopic image and operative field simultaneously. The proposed advantages of HUD include a high-resolution monocular image, which affords the surgeon mobility and reduces vertigo and eyestrain. However, this technology has not yet been widely adopted.

FIG. 11.

The Hopkins rod lens telescope includes a series of optical rods that effectively transmit light to the eyepiece. The video camera is placed on the eyepiece to provide the working image. The image is only as clear as the weakest link in the image chain. (Reproduced with permission from Prescher et al. 46 )

There has been recent interest in three-dimensional endoscopy. Three-dimensional laparoscopy provides the additional depth of field that is lost with two-dimensional endosurgery and allows greater facility for novice laparoscopists performing complex tasks of dexterity, including suturing and knot tying. 51 The advantages of three-dimensional systems are less obvious to experienced laparoscopists. Additionally, because three-dimensional systems require the flickering of two similar images, which are resolved with special glasses, the images’ edges become fuzzy and resolution is lost. The optical accommodatioecessary to rectify these slightly differing images negates any advantage offered by the additional depth of field.

Energy Sources for Endoscopic and Endoluminal Surgery

MIS uses conventional energy sources, but the requirement of bloodless surgery to maintain optimal visualization has spawned new ways of applying energy. The most common energy source is radiofrequency (RF) electrosurgery using an alternating current with a frequency of 500,000 cycles/s (Hz). Tissue heating progresses through the well-known phases of coagulation (60°C), vaporization and desiccation (100°C), and carbonization (>200°C). 52

The two most common methods of delivering RF electrosurgery are with monopolar and bipolar electrodes. With monopolar electrosurgery a remote ground plate on the patient’s leg or back receives the flow of electrons that originate at a point source, the surgical electrode. A fine-tipped electrode causes a high current density at the site of application and rapid tissue heating. Monopolar electrosurgery is inexpensive and easy to modulate to achieve different tissue effects. 53 A short-duration, high-voltage discharge of current (coagulation current) provides extremely rapid tissue heating. Lower-voltage, higher-wattage current (cutting current) is better for tissue desiccation and vaporization. When the surgeon desires tissue division with the least amount of thermal injury and least coagulation necrosis, a cutting current is used.

With bipolar electrosurgery the electrons flow between two adjacent electrodes. The tissue between the two electrodes is heated and desiccated. There is little opportunity for tissue cutting when bipolar current is used, but the ability to coapt the electrodes across a vessel provides the best method of small-vessel coagulation without thermal injury to adjacent tissues 54 (FIG. 12).

FIG. 12.

An example of bipolar coagulation devices. The flow of electrons passes from one electrode to the other and the intervening tissue is heated and desiccated.

In order to avoid thermal injury to adjacent structures, the laparoscopic field of view must include all uninsulated portions of the electrosurgical electrode. In addition, the integrity of the insulation must be maintained and assured. Capacitive coupling occurs when a plastic trocar insulates the abdominal wall from the current; in turn the current is bled off of a metal sleeve or laparoscope into the viscera 52 (Fig. 13–13A). This may result in thermal necrosis and a delayed fecal fistula. Another potential mechanism for unrecognized visceral injury may occur with the direct coupling of current to the laparoscope and adjacent bowel 52 (FIG. 13B).

FIG. 13.

A. Capacitive coupling occurs as a result of high current density bleeding from a port sleeve or laparoscope into adjacent bowel. B. Direct coupling occurs when current is transmitted directly from the electrode to a metal instrument or laparoscope, and then into adjacent tissue. (Reproduced with permission from Odell. 52 )

Another method of delivering radiofrequency electrosurgery is argon beam coagulation. This is a type of monopolar electrosurgery in which a uniform field of electrons is distributed across a tissue surface by the use of a jet of argon gas. The argon gas jet distributes electrons more evenly across the surface than does spray electrofulguration. This technology has its greatest application for coagulation of diffusely bleeding surfaces such as the cut edge of liver or spleen. It is of less use in laparoscopic procedures because the increased intra-abdominal pressures created by the argon gas jet can increase the chances of a gas embolus. It is paramount to vent the ports and closely monitor insufflation pressure when using this source of energy within the context of laparoscopy.

With endoscopic endoluminal surgery, radiofrequency alternating current in the form of a monopolar circuit represents the mainstay for procedures such as snare polypectomy, sphincterotomy, lower esophageal sphincter ablation, and “hot” biopsy. 55,56 A grounding (“return”) electrode is necessary for this form of energy. Bipolar electrocoagulation is used primarily for thermal hemostasis. The electrosurgical generator is activated by a foot pedal so the endoscopist may keep both hands free during the endoscopic procedure.

Gas, liquid, and solid-state lasers have been available for medical application since the mid-1960s. 57 The CO₂ laser (wavelength 10.6 m) is most appropriately used for cutting and superficial ablation of tissues. It is most helpful in locations unreachable with a scalpel such as excision of vocal cord granulomas. The CO₂ laser beam must be delivered with a series of mirrors and is therefore somewhat cumbersome to use. The next most popular laser is the neodymium yttrium-aluminum-garnet (Nd:YAG) laser. Nd:YAG laser light is 1.064 m (1064 nm) in wavelength. It is in the near-infrared portion of the spectrum, and, like CO₂ laser light, is invisible to the naked eye. A unique feature of the Nd:YAG laser is that 1064-nm light is poorly absorbed by most tissue pigments and therefore travels deep into tissue. 58 Deep tissue penetration provides deep tissue heating (FIG. 14). For this reason the Nd:YAG laser is capable of the greatest amount of tissue destruction with a single application. 57 Such capabilities make it the ideal laser for destruction of large fungating tumors of the rectosigmoid, tracheobronchial tree, or esophagus. A disadvantage is that the deep tissue heating may cause perforation of a hollow viscus.

When it is desirable to coagulate flat lesions in the cecum, a different laser should be chosen. The frequency-doubled Nd:YAG laser, also known as the KTP laser (potassium thionyl phosphate crystal is used to double the Nd:YAG frequency), provides 532-nm light. This is in the green portion of the spectrum, and at this wavelength, selective absorption by red pigments in tissue (such as hemangiomas and arteriovenous malformations) is optimal. The depth of tissue heating is intermediate, between those of the CO₂ and the Nd:YAG lasers. Coagulation (without vaporization) of superficial vascular lesions can be obtained without intestinal perforation. 58

In flexible gastrointestinal endoscopy, the CO₂ and Nd:YAG lasers have largely been replaced by heater probes and endoluminal stents. The heater probe is a metal ball that is heated to a temperature (60 to 100°C) that allows coagulation of bleeding lesions without perforation.

Photodynamic therapy (PDT) is a palliative treatment for obstructing cancers of the gastrointestinal tract. 59 Patients are given an intravenous dose of porfimer sodium, which is a photosensitizing agent that is taken up by malignant cells. Two days after administration, the drug is endoscopically activated using a laser. The activated porfimer sodium generates oxygen free radicals, which kills the tumor cells. The tumor is later endoscopically débrided. The use of this modality for definitive treatment of early cancers is in experimental phases and has yet to become established.

A unique application of laser technology provides extremely rapid discharge (<10^–6 s) of large amounts of energy (>10³ volts). These high-energy lasers, of which the pulsed dye laser has seen the most clinical use, allow the conversion of light energy to mechanical disruptive energy in the form of a shock wave. Such energy can be delivered through a quartz fiber, and with rapid repetitive discharges, can provide sufficient shock-wave energy to fragment kidney stones and gallstones. 60 Shock waves also may be created with miniature electric spark-plug discharge systems known as electrohydraulic lithotriptors. These devices also are inserted through thin probes for endoscopic application. Lasers have the advantage of pigment selectivity, but electrohydraulic lithotriptors are more popular because they are substantially less expensive and are more compact.

Methods of producing shock waves or heat with ultrasonic energy are also of interest. Extracorporeal shockwave lithotripsy creates focused shock waves that intensify as the focal point of the discharge is approached. When the focal point is within the body, large amounts of energy are capable of fragmenting stones. Slightly different configurations of this energy can be used to provide focused internal heating of tissues. Potential applications of this technology include the ability to noninvasively produce sufficient internal heating to destroy tissue without an incision.

A third means of using ultrasonic energy is to create rapidly-oscillating instruments that are capable of heating tissue with friction; this technology represents a major step forward in energy technology. 61 An example of its application is the laparoscopic coagulation shears (LCS) device (Harmonic Scalpel), which is capable of coagulating and dividing blood vessels by first occluding them and then providing sufficient heat to weld the blood vessel walls together and to divide the vessel (FIG. 15). This nonelectric method of coagulating and dividing tissue with a minimal amount of collateral damage has facilitated the performance of numerous endosurgical procedures. 62 It is especially useful in the control of bleeding from medium-sized vessels that are too big to manage with monopolar electrocautery and require bipolar desiccation followed by cutting.

FIG. 15.

The Harmonic Scalpel has revolutionized hemostasis and dissection in minimally-invasive surgery and has significantly facilitated the performance of advanced laparoscopic and thoracoscopic procedures. Ultrasonic energy is used to create a rapidly oscillating “working arm” which serves to heat intervening tissue with friction, which fuses the cell membranes together.

Instrumentation

Hand instruments for MIS usually are duplications of conventional surgical instruments made longer, thinner, and smaller at the tip. It is important to remember that when grasping tissue with laparoscopic instruments, a greater force is applied over a smaller surface area, which increases the risk for perforation or injury. 63

Certain conventional instruments such as scissors are easy to reproduce with a diameter of 3 to 5 mm and a length of 20 to 45 cm, but other instruments, such as forceps and clamps, cannot provide remote access. Different configurations of graspers were developed to replace the various configurations of surgical forceps and clamps. Standard hand instruments are 5 mm in diameter and 30 cm in length, but smaller and shorter hand instruments are now available for pediatric surgery, for microlaparoscopic surgery, and for arthroscopic procedures. 63 A unique laparoscopic hand instrument is the monopolar electrical hook. This device is usually configured with a suction and irrigation apparatus to eliminate smoke and blood from the operative field. The monopolar hook allows tenting of tissue over a bare metal wire with subsequent coagulation and division of the tissue.

Robotic Assistance

The term “robot” defines a device that has been programmed to perform specific tasks in place of those usually performed by people. The equipment that has been introduced under the heading of robotic assistance would perhaps be more aptly termed computer-assisted surgery, as it is controlled entirely by the surgeon for the purpose of improving team performance. An example of computer-assisted surgery includes laparoscopic camera holders, which enable the surgeon to maneuver the laparoscope either with head movements or voice activation (FIG. 16). Randomized studies with such camera holders have demonstrated a reduction in operative time, steadier image, and a reduction in the number of required laparoscope cleanings. 64 This device has the advantage of eliminating the need for a human camera holder, which serves to free valuable operating room personnel for other duties.

FIG. 16.

The surgeon controlled computer-assisted camera holder obviates the need for an additional assistant. This device may reduce operative times and provide a steadier image.

Another form of computer assistance involves the use of voice-activated system controls for the camera, light source, insufflators, and telephone. Studies have demonstrated a reduction in the time required to perform these tasks when compared to human intervention. 65

Room Setup and the Minimally-Invasive Suite

Nearly all MIS, whether using fluoroscopic, ultrasound, or optical imaging, incorporates a video monitor as a guide. Occasionally two images are necessary to adequately guide the operation, as in procedures such as endoscopic retrograde cholangiopancreatography (ERCP), laparoscopic common bile duct exploration, and laparoscopic ultrasonography. When two images are necessary, the images should be displayed on two adjacent video monitors or projected on a single screen with a picture-in-picture effect. The video monitor(s) should be set across the operating table from the surgeon. The patient should be interposed between the surgeon and the video monitor; ideally, the operative field also lies between the surgeon and the monitor. In pelviscopic surgery it is best to place the video monitor at the patient’s feet, and in laparoscopic cholecystectomy, the monitor is placed at the 10 o’clock position (relative to the patient) while the surgeon stands on the patient’s left at the 4 o’clock position. The insufflating and patient-monitoring equipment ideally also is placed across the table from the surgeon, so that the insufflating pressure and the patient’s vital signs and end-tidal CO₂ tension can be monitored.

The development of the minimally-invasive surgical suite has been a tremendous contribution to the field of laparoscopy in that it has facilitated the performance of advanced procedures and techniques (FIG. 17). By having the core equipment (monitors, insufflators, and imaging equipment) located within mobile, ceiling-mounted consoles, the surgery team is able to accommodate and make small adjustments rapidly and continuously throughout the procedure. The specifically designed minimally-invasive surgical suite serves to decrease equipment and cable disorganization, ease the movements of operative personnel around the room, improve ergonomics, and facilitate the use of advanced imaging equipment such laparoscopic ultrasound. 66 While having a minimally-invasive surgical suite available is very useful, it is not essential to successfully carry out advanced laparoscopic procedures.

FIG. 17.

An example of a typical minimally-invasive surgery suite. All core equipment is located on easily movable consoles. These operating rooms tend to be larger in size because of the need for multiple types of equipment.

Patient Positioning

Patients usually are placed in the supine position for laparoscopic surgery. When the operative field is the gastroesophageal junction or the left lobe of the liver, it is easiest to operate from between the legs. The legs may be elevated in Allen stirrups or abducted on leg boards to achieve this position. When pelvic procedures are performed, it usually is necessary to place the legs in Allen stirrups to gain access to the perineum. A lateral decubitus position with the table flexed provides the best access to the retroperitoneum when performing nephrectomy or adrenalectomy. For laparoscopic splenectomy, a 45°-tilt of the patient provides excellent access to the lesser sac and the lateral peritoneal attachments to the spleen. For thoracoscopic surgery, the patient is placed in the lateral position with table flexion in order to open the intercostal spaces and the distance between the iliac crest and costal margin (FIG. 18).

When the patient’s knees are to be bent for extended periods or the patient is going to be placed in a reverse Trendelenburg position for more than a few minutes, deep venous thrombosis prophylaxis should be used. Sequential compression of the lower extremities during prolonged (more than 90 min) laparoscopic procedures increases venous return and provides inhibition of thromboplastin activation.

Special Considerations

Pediatric Considerations

The advantages of MIS in children may be more significant than in the adult population. 67 MIS in the adolescent is little different from that in the adult, and standard instrumentation and trocar positions can usually be used. However, laparoscopy in the infant and young child requires specialized instrumentation. The instruments are shorter (15 to 20 cm), and many are 3 mm in diameter rather than 5 mm. 68 Because the abdomen of the child is much smaller than that of the adult, a 5-mm telescope provides sufficient illumination for most operations. The development of 5-mm clippers and bipolar devices has obviated the need for 10-mm trocars in pediatric laparoscopy. 68 Because the abdominal wall is much thinner in infants, a pneumoperitoneum pressure of 8 mm Hg can provide adequate exposure. Deep venous thrombosis is rare in children, and prophylaxis against thrombosis is probably unnecessary.

Pregnancy

Concerns about the safety of laparoscopic cholecystectomy or appendectomy in the pregnant patient have been eliminated. The pH of the fetus follows the pH of the mother linearly, and therefore fetal acidosis may be prevented by avoiding a respiratory acidosis in the mother. 69 A second concern was that of increased intra-abdominal pressure, but it has been proved that midpregnancy uterine contractions provide a much greater pressure in utero than a pneumoperitoneum. Experience in well over 100 cases of laparoscopic cholecystectomy in pregnancy have been reported with uniformly good results. 70 The operation should be performed during the second trimester if possible. Protection of the fetus against intraoperative x-rays is imperative. Some believe it advisable to track fetal pulse rates with a transvaginal ultrasound probe. Access to the abdomen in the pregnant patient should take into consideration the height of the uterine fundus, which reaches the umbilicus at 20 weeks. In order not to damage the uterus or its blood supply, most surgeons feel that the open (Hasson) approach should be used in favor of direct puncture laparoscopy. The patient should be positioned slightly on the left side in order to avoid compression of the vena cava by the uterus. Because pregnancy poses a risk for thromboembolism, sequential compression devices are essential for all procedures.

Cancer

MIS techniques have been used for many decades to provide palliation for the patient with an obstructive cancer. Laser treatment, intracavitary radiation, stenting, and dilation are outpatient techniques that can be used to reestablish the continuity of an obstructed esophagus, bile duct, ureter, or airway. MIS techniques also have been used in the staging of cancer. Mediastinoscopy is still used occasionally before thoracotomy to assess the status of the mediastinal lymph nodes. Laparoscopy also is used to assess the liver in patients being evaluated for pancreatic, gastric, or hepatic resection. New technology and greater surgical skills allow for accurate minimally-invasive staging of cancer. 71 Occasionally it is appropriate to perform palliative measures (e.g., laparoscopic gastrojejunostomy to bypass a pancreatic cancer) at the time of diagnostic laparoscopy if diagnostic findings preclude attempts at curative resection. 72

The most controversial role of MIS techniques is that of providing potentially curative surgery to the patient with cancer. It is possible to perform laparoscopy-assisted colectomy, gastrectomy, pancreatectomy, and hepatectomy in patients with intra-abdominal malignant disease, as well as thoracoscopic esophagectomy and pneumonectomy in patients with intrathoracic malignant disease. There are not yet enough data to indicate whether minimally-invasive surgical techniques provide survival rates or disease-free intervals comparable to those of conventional surgical techniques. It has been proven that in laparoscopy-assisted colectomy and gastrectomy a number of lymph nodes equal to that of an open procedure can be removed without any compromise of resection margins. A second concern centers on excessive tumor manipulation and the possibility that cancer cells would be shed during the dissection. Alarming reports of trocar site implantation with viable cancer cells have appeared in the literature.

Considerations in the Elderly and Infirm

Laparoscopic cholecystectomy has made possible the removal of a symptomatic gallbladder in many patients previously thought to be too elderly or too ill to undergo a laparotomy. Older patients are more likely to require conversion to celiotomy because of disease chronicity. 73

Operations on these patients require close monitoring of anesthesia. The intraoperative management of these patients may be more difficult with laparoscopic access than with open access. The advantage of MIS lies in what happens after the operation. Much of the morbidity of surgery in the elderly is a result of impaired mobility. 73 In addition, pulmonary complications, urinary tract sepsis, deep venous thrombosis, pulmonary embolism, congestive heart failure, and myocardial infarction often are the result of improper fluid management and decreased mobility. By allowing rapid and early mobilization, laparoscopic surgery has made possible the safe performance of procedures in the elderly and infirm.

Cirrhosis and Portal Hypertension

Patients with hepatic insufficiency pose a significant challenge for any type of surgical intervention. 74 The ultimate surgical outcome in this population relates directly to the degree of underlying hepatic dysfunction. 75 Often, this group of patients has minimal reserve, and the stress of an operation will trigger complete hepatic failure or hepatorenal syndrome. These patients are at risk for major hemorrhage at all levels, including trocar insertion, operative dissection in a field of dilated veins, and secondary to an underlying coagulopathy. 75 Additionally, ascitic leak from a port site may occur, leading to bacterial peritonitis. Therefore a watertight port site closure should be carried out in all patients.

It is essential that the surgeon be aware of the Child class of severity of cirrhosis of the patient prior to intervening so that appropriate preoperative optimization can be completed. For example, if a patient has an eroding umbilical hernia and ascites, a preoperative paracentesis or transjugular intrahepatic portosystemic shunt (TIPS) procedure in conjunction with aggressive diuresis may be considered. Because these patients commonly are intravascularly depleted, insufflation pressures should be reduced in order to prevent a decrease in cardiac output and minimal amounts of low-salt intravenous fluids should be given.

Economics of Minimally-Invasive Surgery

Minimally-invasive surgical procedures reduce the costs of surgery most when length of hospital stay can be shortened. For example, shorter hospital stays can be demonstrated in laparoscopic cholecystectomy, fundoplication, splenectomy, and adrenalectomy. Procedures such as inguinal herniorrhaphy that are already performed as outpatient procedures are less likely to provide cost advantage. Procedures that still require a 4- to 7-day hospitalization, such as laparoscopy-assisted colectomy, are even less likely to deliver a lower bottom line than their open-surgery counterparts. Nonetheless, with responsible use of disposable instrumentation and a commitment to the most effective use of the inpatient setting, most laparoscopic procedures can be made less expensive than their conventional equivalents.

Robotic Surgery

With the development of advanced laparoscopic procedures, the limitations of minimally-invasive surgical techniques and instrumentation have become accentuated. For example, the mobility and positioning of a laparoscopic instrument is limited by the placement of the port site on the abdominal wall. This may prevent the surgeon from obtaining the desired instrument angle and position to perform a complex maneuver. In addition, the fine motor movements required to perform complex minimally-invasive surgical procedures may be difficult to perform with standard laparoscopic instruments and imaging. Computer-enhanced (“robotic”) surgery was developed with the intent of circumventing the limitations of laparoscopy and thoracoscopy, and to make minimally-invasive surgical techniques accessible to those without a laparoscopic background. 76 In addition, remote site surgery (telesurgery), in which the surgeon is a great distance from the patient (e.g., combat or space), has potential future applications. This was recently exemplified when a team of surgeons located in New York performed a cholecystectomy on a patient located in France. 77

These devices offer a three-dimensional view with hand- and wrist-controlled instruments that possess multiple degrees of freedom, thereby facilitating surgery with a one-to-one movement ratio that mimics open surgery (FIG. 19). Additionally, computer-enhanced surgery also offers tremor control. The surgeon is physically separated from the operating table and the working arms of the device are placed over the patient (FIG. 20). An assistant remains at the bedside and changes the instruments as needed.

FIG. 19.

Robotic instruments and hand controls. The surgeon is in a sitting position and the arms and wrists are in an ergonomic and relaxed position.

FIG. 20.

Room set-up and position of surgeon and assistant for robotic surgery.

Because this equipment is very costly, a primary limitation to its uniform acceptance has been attempting to achieve increased value in the form of improved clinical outcomes. There have been two randomized controlled trials that compared robotic and conventional laparoscopic approaches to Nissen fundoplication. 78,79 While there was a reduction in operative time, there was no difference in ultimate outcome. Similar results have been achieved for laparoscopic cholecystectomy. 80 Finally, it may be too early in its development (due to bulky equipment, difficulty in accessing patients, and limited instrumentation) for widespread adoption of this technology.

Endoluminal Surgery

The fields of vascular surgery, interventional radiology, neuroradiology, gastroenterology, general surgery, pulmonology, and urology all encounter clinical scenarios that require the urgent restoration of luminal patency of a “biologic cylinder.” 81 Based on this need, fundamental techniques have been pioneered that are applicable to all specialties and virtually every organ system. As a result, all minimally-invasive surgical procedures, from coronary artery angioplasty to palliation of pancreatic malignancy, involve the use of an endoluminal balloon, dilator, prostheses, biopsy forceps, chemical agent, or thermal technique 81 (Table 13-2). Endoluminal balloon dilators may be inserted through an endoscope, or they may be fluoroscopically guided. Balloon dilators all have low compliance—that is, the balloons do not stretch as the pressure within the balloon is increased. The high pressures achievable in the balloon create radial expansion of the narrowed vessel or orifice, usually disrupting the atherosclerotic plaque, the fibrotic stricture, or the muscular band (e.g., esophageal achalasia). 82

Once the dilation has been attained, it is frequently beneficial to hold the lumen open with a stent. 83 Stenting is particularly valuable in treating malignant lesions and in endovascular procedures (FIG. 21). Stenting usually is not applicable for long-term management of benign gastrointestinal strictures except in patients with limited life expectancy 83–85 (FIG. 22A and B).

FIG. 21.

The deployment of a metal stent across an isolated vessel stenosis is illustrated. [Reproduced with permission from Hunter JG, Sackier JM (eds): Minimally-Invasive Surgery. New York: McGraw-Hill, 1993, p 325.]

FIG. 22.

This is an esophagram in a patient with severe dysphagia secondary to advanced esophageal cancer (A) before and (B) after placement of a covered self-expanding metal stent.

A variety of stents are available that are divided into two basic categories, plastic stents and expandable metal stents 84 (FIG. 23). Plastic stents came first and are used widely as endoprostheses for temporary bypass of obstructions in the biliary or urinary systems. Metal stents generally are delivered over a balloon and expanded with the balloon to the desired size. These metal stents usually are made of titanium or nitinol. Although great progress has been made with expandable metal stents, two problems remain: propensity for tissue ingrowth through the interstices of the stent and stent migration. Ingrowth may be an advantage in preventing stent migration, but such tissue ingrowth may occlude the lumen and cause obstruction anew. This is a particular problem when stents are used for palliation of gastrointestinal malignant growth, and may be a problem for the long-term use of stents in vascular disease. Filling the interstices with Silastic or other materials may prevent tumor ingrowth, but also makes stent migration more likely. In an effort to minimize stent migration, stents have been incorporated with hooks and barbs.

FIG. 23.

Covered self-expanding metal stents. These devices can be placed fluoroscopically or endoscopically.

Most recently, anticoagulant-eluding coronary artery stents have been placed in specialized centers. 86 This exciting technological advance may dramatically increase the long-term patency rates of stents placed in patients with coronary artery disease and peripheral atherosclerosis.

Intraluminal Surgery

The successful application of minimally-invasive surgical techniques to the lumen of the gastrointestinal tract has hinged upon the development of a port that maintains access to the gastrointestinal lumen while preventing intraperitoneal leakage of intestinal contents and facilitating adequate insufflation 87 (FIG. 24). Procedures that are gaining acceptance include resection of benign and early malignant gastric tumors, transanal resection of polyps (transanal endoscopic microsurgery), pancreatic cyst gastrostomy, and biliary sphincterotomy.

FIG. 24.

An illustration of a radially expanding trocar used for intraluminal surgery. The stomach is insufflated using a nasogastric tube, and the anterior gastric wall is pierced with the trocar under laparoscopic guidance. A balloon is inflated and used to draw the stomach up to the anterior abdominal wall. [Reproduced with permission from Eubanks WS, Swanstrom LL, Soper NJ (eds): Mastery of Endoscopic and Laparoscopic Surgery. Philadelphia: Lippincott Williams & Wilkins, 1999, p 215.]

The location of the lesion within the gastrointestinal tract is of utmost importance when considering an intraluminal approach. For example, a leiomyoma that is located on the anterior gastric wall may not be amenable to intraluminal resection because the working ports must also penetrate the anterior surface of the stomach. Preoperative endoscopy and endoscopic ultrasound should be routinely employed in order to determine resectability. 87

Education and Skill Acquisition

Surgeons in Training and Skill Acquisition

Surgeons in training acquire their skills in minimally-invasive techniques through a series of operative experiences of graded complexity. This training occurs on patients. With the recent constraints placed on resident work hours, providing adequate minimally-invasive training to future surgeons within a relatively brief time frame has become of paramount importance.

Laparoscopic surgery demands a unique set of skills that require the surgeon to function at the limit of his or her psychomotor abilities. The introduction of virtual reality training devices presents a unique opportunity to improve and enhance experiential learning in endoscopy and laparoscopy for all surgeons. This technology has the advantage of enabling objective measurement of psychomotor skills, which can be used to determine progress in skill acquisition, and ultimately technical competency. 88,89 This technology will most likely be used to create benchmarks for the performance of future minimally-invasive techniques. In addition, virtual reality training enables the surgeon to build an experience base prior to venturing into the operating room. 90 Be that as it may, no studies have demonstrated that simulator training improves overall patient outcome.

Some hospitals and training programs have established virtual reality and laparoscopic training centers that are accessible at all hours for surgeons’ use.

Telementoring

In response to the Institute of Medicine’s call for the development of unique technologic solutions to deliver health care to rural and underserved areas, surgeons are beginning to explore the feasibility of telementoring. Teleconsultation or telementoring is two-way audio and visual communication between two geographically separated providers. This communication can take place in the office setting, or directly in the operating room when complex scenarios are encountered. Although local communication channels may limit its performance in rural areas, the technology is available and currently being employed (FIG. 25).

FIG. 25.

Teleconsultation and telementoring are carried out between two providers who are geographically separated. The console has a video camera, microphone, and flat screen display which can be positioned at the operating room table or in the clinic.

Innovation and Introduction of New Procedures

The revolution in minimally-invasive general surgery, which occurred in 1990, created ethical challenges for the profession. The problem was this: If competence is gained from experience, how was the surgeon to climb the competence curve (otherwise known as the learning curve) without injuring patients? If it was indeed impossible to achieve competence without making mistakes along the way, how should one effectively communicate this to patients such that they understand the weight of their decisions? Even more fundamentally important is determining the path that should be followed before one recruits the first patient for a new procedure.

Although procedure development is fundamentally different than drug development (i.e., there is great individual variation in the performance of procedures, but no difference between one tablet and the next), adherence to a process similar to that used to develop a new drug is a reasonable path for a surgical innovator. At the outset the surgeon must identify the problem that is not solved with current surgical procedures. For example, while the removal of a gallbladder through a Kocher incision is certainly effective, it creates a great deal of disability, pain, and scarification. As a result of those issues, many patients with very symptomatic biliary colic delayed operation until life-threatening complications occurred. Clearly there was a need for developing a less invasive approach (FIG. 26).

Once the opportunity has been established, the next step involves a search through other disciplines for technologies and techniques that might be applied. Again, this is analogous to the drug industry, where secondary drug indications have often turned out to be more therapeutically important than the primary indication for drug development. The third step is in vivo studies in the most appropriate animal model. Certainly these types of studies are controversial because of the resistance to animal experimentation, and yet without such studies many humans would be injured or killed during the developmental phase of medical drugs, devices, and techniques. These steps are often called the preclinical phase of procedure development.

The decision as to when such procedures are ready to come out of the lab is a difficult one. Put simply, the procedure should be reproducible, provide the desired effect, and not have serious side effects. Once these three criteria are reached, the time for human application has arrived. Before the surgeon discusses the new procedure with his patient, it is important to achieve full institutional support. Clearly, involvement of the medical board, the chief of the medical staff, and the institutional review board are essential before commencing on a new procedure. These bodies are responsible for the use of safe, high quality medical practices within their institution, and they will demand that great caution and all possible safeguards are in place before proceeding.

The dialogue with the patient who is to be first must be thorough, brutally honest, and well documented. The psychology that allows a patient to decide to be first is quite interesting, and may under certain circumstances require psychiatric evaluation. Certainly if a dying cancer patient has a chance with a new drug, this makes sense. Similarly, if the standard surgical procedure has a high attendant morbidity and the new procedure offers a substantially better outcome, the decision to be first is understandable. On the other hand, when the benefits of the new approach are small and the risks are largely unknown, a more complete psychological profile may be necessary before proceeding.

For new surgical procedures, it is generally wise to assemble the best possible operative team, including a surgeon experienced with the old technique, and assistants who have participated in the earlier animal work. This initial team of experienced physicians and nurses should remain together until full competence with the procedure is attained. This may take 10 procedures, or it may take 50 procedures. The team will know that it has achieved competence when the majority of procedures take the same length of time, and the team is relaxed and sure of the flow of the operation. This will complete phase I of the procedure development.

In phase II, the efficacy of the procedure is tested in a nonrandomized fashion. Ideally, the outcome of new techniques must be as good or better than the procedure that is being replaced. This phase should occur at several medical centers to prove that good outcomes are achievable outside of the pioneering institution. These same requirements may be applied to the introduction of new technology into the operating room. The value equation requires that the additional measurable procedure quality exceeds the additional measurable cost to the patient or health care system. In phase III, a randomized trial pits the new procedure against the old.

Once the competence curve has been climbed, it is appropriate for the team to engage in the education of others. During the ascension of the competence curve, other learners in the institution (i.e., surgical residents) may not have the opportunity to participate in the first case series. While this may be difficult for them to swallow, the best interest of the patient must be put before the education of the resident.

The second stage of learning occurs when the new procedure has proven its value and a handful of experts exist, but the majority of surgeons have not been trained to perform the new procedure. In this setting, it is relatively unethical for surgeons to forge ahead with a new procedure in humans as if they had spent the same amount of time in intensive study that the first team did. The fact that one or several surgical teams were able to perform an operation does not ensure that all others with the same medical degrees can perform the operation with equal skill. It behooves the learners to contact the experts and request their assistance to ensure an optimal outcome at the new center. While it is important that the learners contact the experts, it is equally important that the experts be willing to share their experience with their fellow professionals. As well, the experts should provide feedback to the learners as to whether they feel the learners are equipped to forge ahead on their own. If not, further observation and assistance from the experts are required. While this approach may sound obvious, it is fraught with difficulties. In many situations ego, competitiveness, and monetary concerns have short-circuited this process and led to poor patient outcomes. To a large extent, MIS has recovered from the black eye that it received early in development, when inadequately trained surgeons caused an excessive number of significant complications.

If innovative procedures and technologies are to be developed and applied without the mistakes of the past, surgeons must be honest when they answer these questions: Is this procedure safe? Would I consider undergoing this procedure if I developed a surgical indication? Is the procedure as good or better than the procedure it is replacing? Do I have the skills to apply this procedure safely and with equivalent results to the more experienced surgeon? If the answer to any of these questions is “no,” or “I don’t know,” there is a professional obligation to seek another procedure or outside assistance before subjecting a patient to the new procedure.

LAPAROSCOPIC MANAGEMENT OF BILIARY STONE DISEASE

The management of biliary stones diseases has dramatically changed with the advent of the Laparoscopic Cholecystectomy. It has now become a true outpatient laparoscopic procedure with negligible morbidity.

In the past few years, our surgical team has designed and revised numerous management protocols for various clinical settings effectively achieving impressive improvements in our surgical performance for the treatment of biliary stone diseases. This chapter will describe these management protocols and our latest technical updates.

The original Laparoscopic Cholecystectomy technique has undergone a vast maturation process over the past decade. Various technical steps has been modified and adapted to improve surgical performance and clinical outcome. As a result, nowadays, most surgeons in the Western World can safely perform a Laparoscopic Cholecystectomy with a minimal conversion rate.

 ROUTINE INTRA-OPERATIVE CHOLANGIOGRAPHY

Routine operative cholangiography is recommended by most laparoscopic authors in the United States. However, recent  reports demonstrate it does not significantly decrease the rate of common bile duct injury in cases where the anatomy is well-identified. Our recommendation is that routine intraoperative cholangiography should be performed by inexperienced laparoscopic surgeons and in cases where the anatomy is not well-defined.

 IDENTIFYING PATIENTS WITH CHOLEDOCHOLITHIASIS

In order to achieve the level of Maximum Surgical Performance with this procedure, patients at high risk of presenting with Common Bile Duct Stones need to be identified pre-operatively. The simplest methods to initially identify these patients are:

1) History and Physical Examination,

2) Liver Function Studies,

3) Sonographic Findings.

Patients with a recent history of gallstone pancreatitis, jaundice, or presenting with such symptoms are at a high risk of having common bile duct pathology; the same is valid for patients with altered liver function studies. The most accurate studies are the Serum Transaminases (SGOT, SGPT). Elevations of these enzymes over 20% of their normal values are significant. But patients with severe, acute cholecystitis can occasionally generate such elevations. Also,  extreme elevations of these two enzymes could represent hepatocytes necrosis as seen in hepatitis. The bilirubin level may also be elevated in certain patients with acute cholecystitis, but elevations above 2.5 or 3.0 mg/dl could identify a patient with choledocholithiasis. Finally, we find the enzymes LDH and GGTP to have no real specific value in this clinical setting.

It is interesting that in spite of our intensive efforts to identify Common Bile Duct pathology preoperatively, missed Common Bile Duct Stones are found in 1.92% of all patients. Of these patients 76% will require additional surgical intervention (ERCP).

 ROUTINE INTRA-OPERATIVE CHOLANGIOGRAPHY

This technology is being used with increasing frequency in our surgical service to identify patients with choledocholithiasis. A GE Magnetic Resonance machine was used for all studies. To date the specificity and accuracy of these studies in our services is 98.2% for common bile duct stones over 1 mm in size. 

 ROUTINE INTRA-OPERATIVE CHOLANGIO-SONOGRAPHY

Intra-operative cholangio-sonography is being used in many medical centers to rule out common bile duct stone. Although this modality was used oumerous occasions, we found it too time consuming to be used on a routine basis.

 ANTERIOR OR SUBTOTAL LAPAROSCOPIC CHOLECYSTECTOMY

In our never-ending quest of increasing surgical performance,  we meticulously analyzed when and why conversion occurred during the performance of a laparoscopic cholecystectomy.  Most of them occurred in patients with acute, severe and gangrenous cholecystitis. Thus, we introduced the anterior-subtotal laparoscopic cholecystectomy to be used ONLY in these clinical settings when a standard laparoscopic Cholecystectomy could not be completed safely. (Refer to Technique and Surgical Performance later in chapter).

 THE DECREASING IMPACT OF THE LAPAROSCOPIC CBD EXPLORATION

Significant problems have impaired the growth of Laparoscopic Common Bile Duct exploration. This technique is simply not easy to perform and good results are only achieved by experienced operators. In addition, this procedure is hardware intensive and the choledochoscopes are not as reliable as they are touted to be. For these reasons it quickly become obvious to us, the indications for this procedure were becoming more and more limited. 

Our surgical team promotes the use of Endoscopic Retrograde Cholangiography and Papillotomy. When not feasible, a laparoscopic transcystic or via anterior choledochotomy CBDE is performed. It should be mentioned that some critics claim there are no studies available on the long term effects of endoscopic papillotomies and that it represents a significant additional cost. Although, this statement is correct, there are also no reports of long term adverse effects of such procedures. 

 CLASSIFYING THE BILIARY STONE PATIENT

   IDENTIFYING PATIENTS WITH CHOLEDOCHOLITHIASIS

 MANAGEMENT PROTOCOL DIAGRAM

THE TECHNIQUES

·        Operating Room Set-up

·        Instruments

·        Trocars Placement

·        Additional Informed Consent

·        Technique: Standard Lap- Cholecystectomy

·        Technique: Intra-operative Cholangiography

·        Technique: Laparoscopic Common Bile Duct Exploration – Transcystic

·        Technique: Laparoscopic Common Bile Duct Exploration – Choledochotomy

·        Technique: Anterior/subtotal Laparoscopic Cholecystectomy

·        Technique: LapChole with Cystic Duct Cannulation

·        Return to Chapter Table of Contents

·         

OPERATING ROOM SET-UP

TROCARS PLACEMENT

STANDARD LAPAROSCOPIC CHOLECYSTECTOMY

The pneumoperitoneum is obtained in the usual fashion. The trocars are inserted as indicated.

 STEP 1: EXPOSING THE CYSTIC DUCT AND ARTERY

The stationary grasper [1: lateral position] is utilized to grasp the tip of the gallbladder and push it over the anterior edge of the liver by progressive traction. Hartmann’s pouch is pulled upward. This exposes the cystic duct and artery as well as the common bile duct. It is important to constantly maintain this traction. In most cases, the scrub nurse or assistant hold this retractor. In difficult, longer cases, the handle of the grasper is clamped onto the skin of the abdomen or onto the protective field. The patient is now positioned head down.

CAUTION: It is not always possible to push the tip of the gallbladder (Re: cirrhotic patients) over the anterior hepatic edge. In these cases, gently push its tip against the liver, being very meticulous not to penetrate the parenchyma of the liver.

 STEP 2: DISSECTING THE CYSTIC DUCT AND ARTERY

Once the field is exposed, Hartmann’s pouch is grasped with the lateral working grasper and pulled laterally, further exposing Calot’s triangle. The operator will then pass a dissecting grasper through the subxyphoid trocar and begin to identify the cystic duct. In acute cholecystitis, edematous layers of tissue will have to be stripped downward to expose the cystic duct.

The subxyphoid  Dolphin Nose Grasper instrument is passed behind the cystic duct or actually between the cystic duct and the cystic artery. In most cases, the duct is anterior to the artery.

CAUTION : Hartmann’s pouch should always be identified and visualized. The dissection of Calot’s triangle can be done safely starting from the pouch and moving toward the cystic duct. This is particularly important in acute cases, when anatomical landmarks are difficult to find. It is essential to visualize Calot’s triangle, which includes the cystic artery, cystic duct and the common bile duct. If visualization of this area becomes difficult, always check the tension on the stationary grasper and the intra-abdominal pressure.

 STEP 3: ROUTINE INTRA-OPERATIVE CHOLANGIOGRAM

To view the technique of Routine Intra-operative Cholangiography.

 STEP 4: TRANSECTING THE CYSTIC DUCT AND ARTERY

At this juncture, the cystic window is created (i.e., free space behind the cystic duct and the cystic artery). The clip applier is inserted via the subxyphoid trocar. The cystic duct and artery are clipped (three clips) as close as possible to the gallbladder. The ENDO CLIP* Applier is then withdrawn and the EndoShears™ instrument is inserted to cut them.

CAUTION: Be very careful to clearly identify the junction of the gallbladder and cystic duct and plan your transection from this anatomical landmark. In doubt, always check with an IOC.

 STEP 5: DISSECTING THE BODY OF THE GALLBLADDER

Hartmann’s pouch is now retracted upward. Using the EndoShears* instrument, the most lower lateral aspect of Hartmann’s pouch should be dissected meticulously.

The ENDO SHEARS*instrument is withdrawn and replaced by the electrocautery hook. The gallbladder is retracted upward and tension is placed on the surgical plane between the gallbladder and its liver bed. The dissection is extended to the top of the gallbladder. Occasionally the grasper holding the cystic duct stump can be used to flip the body of the gallbladder around the stationary grasper which is still holding the fundus of the gallbladder.

In most instances, this dissection will generate smoke which can impair the surgeon’s visualization. This smoke can be aspirated by opening the insufflation of the lateral trocar.

STEP 6: EXTRACTING THE GALLBLADDER

A 10 mm, large grasper is introduced via the sub-xyphoid trocar. The two lateral graspers holding the gallbladder present the gallbladder to the newly introduced large grasper. The gallbladder is pulled from the the intra-abdominal cavity through the same trocar site. This trocar site can enlarged bluntly with a peon clamp of a few millimeters. An Endocatch™ Instrument can be used to remove the specimen.

The intra-abdominal cavity is then thoroughly irrigated with normal saline. All stones that have dropped into the intra-abdominal cavity are retrieved with a morcilator or stone retrieving forceps.

The abdomen is deflated; the trocars removed, and the trocar insertion sites are closed in the usual fashion.

ROUTINE INTRA-OPERATIVE CHOLANGIOGRAM

Additional Instruments:

1.     Storz Cholangiograsper 5 mm

2.     1 Ureteral Catheter 4 or 5 F with Adapter

3.     Dye Used: Renographin 60

 STEP 1: EXPOSING THE CYSTIC DUCT AND ARTERY

The cystic duct is dissected meticulously as close as possible to the gallbladder. The ENDO CLIP* Applier is inserted via the sub-xyphoid trocar and the cystic duct is clipped at its junction with the gallbladder. While maintaining the same exposure, the ENDO CLIP* applier is withdrawn, an ENDO SHEARS* instrument is inserted via the subxyphoid trocar.

An anterior incision is made on the cystic duct.

The ENDO SHEARS* instrument is then withdrawn and a cholangiocatheter grasper with a French #4 catheter is inserted. All the side ports of the catheter have been eliminated by cutting the last 3 cm of the tip. The catheter is inserted into the duct.

In most cases, the intraluminal valves on the cystic duct will make this insertion difficult. However, with the cholangiocatheter only the very tip of the catheter needs to be inserted to ensure the flow of bile enters the common bile duct. The grasper is closed around the duct; the jaws should enclose the entire width of the duct for better performance. The catheter is irrigated, and no leak should be seen around the entry site.

If the injection of dye is difficult and slow, and in most cases it is, use a 10cc syringe to inject the dye.

The cholangiogram is obtained. The following should be visible on the radiogram:

1. The cystic duct

2. The common bile duct with its hepatic bifurcation

3. Renografin in the duodenum

4. Absence of CBD stones

After completing the operative cholangiogram, the cholangiocatheter and grasper are removed.

LAPAROSCOPIC COMMON BILE DUCT EXPLORATION:

TRANS-CYSTIC DUCT

As previously mentioned, the number of laparoscopic common bile duct explorations performed on our surgical service has  dramatically decreased over the past few years. These explorations are now rare and usually performed in post-cholecystectomy patients with Choledocholithiasis who have failed endoscopic retrieval. We strongly believe  Choledocholithiasis is best treated by non-surgical methods such as an Endoscopic Retrograde Cholangiography and Papillotomy.

Two techniques are used to perform a common bile duct exploration via laparoscopy. These are

1) the cystic duct dilatation and retrieval and,

2) the anterior choledochotomy. Nowadays, we almost exclusively use the laparoscopic anterior choledochotomy.

Pre-exploration Work-up: A correct diagnosis should be made prior to the actual initiation of the procedure. An intraoperative cholangiogram or another imaging study should demonstrate common bile duct pathology unequivocally.

 OPERATING ROOM SET-UP:

 Additional Instruments and Hardware:

A second Storz Camera with a monitor

1 – 5 mm trocar (available)

Additional Instruments

1 Storz Ureteroscope- 3.0 mm or 3.5 mm with a 1.5 mm working channel

1 Phantom 5 Plus Balloon Catheter (Microvasive /75cm, 5 Fr./6 mm, 18 Fr.) with Catheter Introducer

1 LeVeen Inflator 10 cc with Pressure Gauge

1 Glide Wire 0.35/150 cm with straight tip

1 Segura Stone Retrieval Stone Basket 2.4F Mini (120 cm)

 The Technique

 STEP 1: THE INTRA-OPERATIVE CHOLANGIOGRAM

This technique is used at the time of a laparoscopic cholecystectomy. An operative cholangiogram has confirmed the presence of a common bile duct stone. At this point, a clip has been placed at the junction of the gallbladder and the cystic duct. The cholangio-catheter has been removed. The cystic duct should not be cut. An intact common bile duct is necessary to maintain sufficient tension for easy access into the cystic duct and the common bile duct.

 STEP 2: CANNULATING THE CYSTIC DUCT

The Phantom 5 Plus Catheter is connected to the LeVeen Inflator with Pressure Gauge. The catheter is inserted via the lateral 5 mm trocar into the intraabdominal cavity. A long 4.5 mm sealed, steel shaft is used to minimize air leaks and to facilitate insertion of the catheter into the cystic duct.

A glide wire is inserted into the central channel of the Phantom 5 Plus Catheter. This glide wire is inserted into the Cystic duct and into the common bile duct using direct vision. The dilating catheter is then passed over the glide wire into the common bile duct. The balloon of the catheter entering the cystic duct is positioned at the entrance of the cystic duct. The balloon is inflated for five minutes at 12 atmospheres of pressure. The entrance of the cystic duct has now been dilated to accommodate a standard 3.0 mm ureteroscope.

 STEP 3: INSERTING THE CHOLEDOCHOSCOPE

The Phantom 5 Plus Catheter is then removed and replaced by the ureteroscope. This scope is either connected to an additional camera and monitor, or to an additional camera with a image splitter. The ureteroscope is inserted into the cystic duct with a high pressure saline flow. It is pushed into the common bile duct which is visualized and fully explored.

 STEP 4: RETRIEVING THE CBD STONES

Once a stone is seen, the tip of the ureteroscope is placed proximal to the stone. A Segura Basket is inserted into the working channel of the ureteroscope, advanced into the common bile duct and passed beyond the stone. It is then opened and slowly withdrawn under direct vision. When the stone is in the basket, the basket is closed and the stone grasped. The entire apparatus, including the ureteroscope and the wire basket, is pulled out of the common bile duct and the cystic duct. The stone is then released into the intraabdominal cavity and retrieved in the usual manner.

LAPAROSCOPIC COMMON BILE DUCT EXPLORATION: CHOLEDOCHOTOMY

 Additional Instruments and Hardware:

A second Storz Camera with a monitor

1 – 5 mm trocar (available)

Biliary Fogarty Catheters (5, 6 F)

Zsabo-Berci Needle Driver or EndoStitch Instrument

Laparoscopic Sutures

T Tube ( Sizes 12 – 18 should be available)

The Technique

This can be performed at the time of a laparoscopic cholecystectomy or in the post-cholecystectomy patient. In the latter group, the trocars used are the same as for a standard laparoscopic cholecystectomy.

 STEP 1: EXPOSING THE CBD

The common bile duct should be equivocally identified. We rarely proceed with a common bile duct exploration if the duct is 1cm or less in diameter. A confirmation of the diagnosis  is imperative either via an intra-operative cholangiography or with an intra-operative sonographic study. A meticulous dissection of the common bile duct is performed using the ENDO SHEARS* Instrument and a non traumatic grasper from the hepatic bifurcation to the superior aspect of the pancreas. A section of the common bile duct of about 2 cm should be exposed. In some cases, the gallbladder is used to give additional retraction as demonstrated in the following picture. An endoscopic suture can be placed on the lower portion of the gallbladder and the lateral aspect of the common bile duct. In most cases however, we perform a choledochotomy without retraction sutures.

 STEP 2: THE ANTERIOR CHOLEDOCHOTOMY

The anterior choledochotomy is performed by inserting the ENDO SHEARS* Instrument via the subxyphoid trocar, grasping the common bile duct with an ENDO DISSECT* Instrument (via the lateral trocar) and incising the CBD (15 to 20mm).

 STEP 3: CLEARING THE CBD

Once the choledochotomy is done,  the common bile duct is flushed using our high pressure irrigation device. A Biliary Fogarty Catheter is then used. It is inserted via the subxyphoid trocar and into the common bile duct, run proximally and distally. This step usually retrieves most of the common bile stones.

 STEP 4: THE CHOLEDOCHOSCOPY

A Choledochoscopy is  performed. An additional camera and monitor are used to connect the flexible 3 mm choledochoscope or ureteroscope. In this setting, larger ureteroscopes can be utilized as the choledochotomy can accommodate larger sizes. Stones are retrieved using a Secura Basket via the working channel of the telescope.

 STEP 5: INSERTING THE T TUBE

Once the common bile duct is shown to be free of stones, a T Tube is inserted. The T Tube is usually inserted via the subxyphoid trocar after its limbs have been cut (each should be 1.0 cm in length). It is then inserted entirely into the intra-abdominal cavity. An additional 5 mm trocar is inserted in the RUQ. A grasper is inserted via this new trocar to grasp the long limb of the T Tube. The T Tube is then pulled through the anterior abdominal wall along with the trocar. The T Tube is then inserted into the common bile duct, using two graspers or ENDO DISSECT*. The common bile duct is sutured closed with endoscopic sutures. A completion Cholangiogram is then obtained.

SUBTOTAL OR ANTERIOR LAPAROSCOPIC CHOLECYSTECTOMY

Indications: Acute, severe, gangrenous Cholecystitis and the inability to complete a safe standard laparoscopic Cholecystectomy.

Operating Room Setup: Same as Standard LapChole

Hardware: Same as Standard LapChole

Instruments: Same as Standard LapChole

Additional Instruments: Two Blake drains with drainage reservoir

All patients are given Toradol (Roche Pharmaceuticals) and Cefizox (Fujisawa USA) during induction.

 The Technique

A standard laparoscopic cholecystectomy has been initiated by the surgeon, at which time he assesses an anterior laparoscopic cholecystectomy should be performed.

Using the stationary or lateral 5 mm grasper, the tip of the fundus of the gallbladder is grasped and retracted cephalad. An ENDO SHEARS* Instrument is inserted via the sub-xyphoid trocar (with electrocautery connection). Using the other lateral grasper, the anterior aspect of the gallbladder is dissected meticulously. The dissection should be extended as low as possible toward the cystic duct without compromising the safety of the procedure. 

Using the ENDO SHEARS* Instrument, the gallbladder is entered and the anterior wall of the gallbladder should be resected. Hemostasis should be controlled with the ENDO SHEARS* Instrument connected to an electrocautery source. Spilled gallstones should be retrieved and removed with a morcilator-type grasper (10 mm). The specimen should be removed via the sub-xyphoid trocar. The gallbladder fossa should be flushed thoroughly with normal saline.

Two Blake™ drains are inserted into the intra-abdominal cavity. The best method for the insertion of these drains is to insert a 5 mm grasper via one of the lateral trocars into the intra-abdominal cavity and out through the sub-xyphoid trocar. The sub-xyphoid trocar is removed. The end of the Blake drain is grasped by the grasper outside the abdominal cavity and pulled back into the intra-abdominal cavity. The lateral grasper pulls it via the 5 mm trocar site. One drain is inserted into the open gallbladder fossa and the other into the sub-hepatic fossa.

The procedure is completed as usual.

 Technical Notes

Postoperative Management: Postoperatively, the clinical behavior of these patients is the same as for all patients undergoing a minimally invasive procedure. The next day they usually are on a regular diet and ambulatory. Unless they have associated medical problems, most patients can be discharged within 48 hours. They are discharged with Blake drains in place. Interestingly, some patients will have a bile leak-drainage noticeable on postoperative day one, and others will not. This is most likely secondary to a blocked cystic duct secondary to an impacted gallstone. Nonetheless, these drains are to remain in place for two weeks or until they cease to drain.

Bile Leak-Drainage: Most patients will have significant bile drainage, as this procedure effectively creates a controlled bilio-cutaneous fistula. The average or mean bilious drainage is two days. The longest recorded drainage has been 21 days. As a rule, in the absence of a distal common bile duct obstruction, all bilious drainage or leaks will cease within three weeks.

Associated Complications: This procedure does not allow the performance of an intra-operative cholangiogram or the placement of a cystic duct cannula. One patient was found postoperatively to have a retained common bile duct stone  requiring an Endoscopic Retrograde Cholangiography and Papillotomy. Another patient developed a sub-phrenic abscess and eventually required a laparotomy.

Impact of Anterior-subtotal Laparoscopic Cholecystectomy On the Conversion Rate: Prior to introducing this procedure, most conversions occurred in patients with acute, severe, and gangrenous cholecystitis. This procedure effectively decreased our conversion rate as soon as it was introduced. Actually, since its introduction, 896 LapCholes were done with only one conversion. This reduction in the conversion rate is probably the most significant advantage of this technique.

MANAGEMENT OF CHOLEDOCHOLITHIASIS WITH A CYSTIC DUCT CATHETER

Controversies in the Management of CBD Stones

In the United States, surgeons perform approximately 600,000 laparoscopic cholecystectomies (LC) per year. LC’s have largely superceded open cholecystectomies (OC) as the preferred method of gallbladder removal, accounting for 80% of such procedures in this country. One limitation of LC as compared to OC is the difficulty in dealing with common bile duct (CBD) stones. CBD stones are present in approximately 15% of patients, and are responsible for considerable morbidity and mortality (specifically pancreatitis and ascending cholangitis) which mandates the removal of such stones.

In OC, surgeons can routinely remove CBD stones via common bile duct exploration (CBDE), a natural extension of the operative procedure. In LC however, techniques for detection of CBD stones (intraoperative cholangiography or IOC) and subsequent removal are beset with pitfalls. IOC, performed by injection of dye via a cystic duct catheter placed surgically, adds significant time to the operative procedure. It also requires commitment of additional equipment and personnel to the operating room, and has a false positive rate of stone detection of up to 12%, sometimes resulting in unnecessary CBDE. Furthermore, the finding of stones on operative cholangiogram obligates the surgeon to perform CBDE, either laparoscopic or open . A laparoscopic CBDE is a time consuming, hardware intensive procedure, has a steep learning curve, is associated with up to a 50% failure rate, and risks injury to the CBD. Conversion to open CBDE negates the value of a laparoscopic procedure. Another alternative in patients with stones seen on IOC is to refer the patient postoperatively for ERCP, papillotomy, and stone removal. However, a technical failure rate of up to 15% in some series could lead to a second operative procedure, open CBDE.

A number of researchers have attempted to define parameters which could be useful in preoperative prediction of CBD stones. This includes the presence of any of several parameters: 1) Increased liver enzymes, 2) Preoperative pancreatitis, jaundice, or cholangitis, 3) A dilated CBD or intraductal stone on ultrasound, is predictive of CBD stones 25-48% of the time. Furthermore, stones can be present up to 8% of the time in the absence of such parameters or risk factors. Strategies to deal with possible CBD stones in patients with risk factors are complex. One strategy is to do preoperative ERCP with removal of stones (if present). The problem is that 50-75% of ERCP’s performed because of the presence of a risk factor will show no stones. Thus, a large number of unnecessary ERCP’s will be performed, with a complication rate of 5-10%, and a technical failure rate of up to 15% (i.e. failure to cannulate CBD). A second strategy is to do IOC on patients with risk factors, and to do intraoperative stone removal if stones are detected. The problem with this, as mentioned is that IOC, is time-consuming and associated with up to 12% false positive rate. Subsequent intraoperative stone removal is both time consuming and risky, and often subjects the patient to an open procedure. A third strategy is to do postoperative ERCP if the IOC shows stones. Again, the problem here is that up to a 15% failure risk associated with ERCP would subject the patient to another surgical procedure to remove the stones.

 USING A CDC FOR A POST-OPERATIVE CHOLANGIOGRAM

We have developed a new and simple technique for cholangiography that we believe will largely supplant existing complicated algorithms for dealing with CBD stones. In this laparoscopic technique, in lieu of performing IOC, we secure a standard ERCP catheter (Microvasive, tapered tip) in the cystic duct intraoperatively and leave the catheter in place after surgery.

Postoperatively, all patients undergo a cholangiogram in the x-ray department via the catheter. If no stones are demonstrated, then the catheter is pulled. If stones are present, then the endoscopist performs postoperative ERCP and papillotomy to remove the stones, and then pulls the transcystic catheter.

THE LAPCHOLE WITH CDC PLACEMENT

Operating Room Setup:Same as Standard LAPCHOLE

Hardware: Same as Standard LAPCHOLE

Instruments: Same as Standard LAPCHOLE

Additional Instruments:

1 Blake Drain with drainage reservoir

1 Ureteral 7 French Ureteral Catheter or

1 Fluoro Tip ERCP Cannula Tapered Tip

 (210 cm – 5 French 1.7 mm with stainless steel stylet)

Technique

The procedure is initiated as described in the Standard LAPCHOLE Chapter.

1. Inserting the Cystic Duct Cannula in the Intraabdominal Cavity

The cystic duct is exposed and clipped at its junction with the gallbladder with an endoclip. Traction is maintained on Hartmann’s pouch to expose the cystic duct. An anterior incision is made with the ENDO SHEARS* instrument.

The cystic duct cannula is inserted via the subxyphoid trocar site. First, the trocar is quickly removed from the subxyphoid site. The site is plugged with a finger and the cannula is inserted bluntly into the intraabdominal cavity under direct vision. When 10 to 15 cm of the cannula is in the intraabdominal cavity, the VERSAPORT* trocar is reinserted bluntly next to the cystic duct cannula. Both the cannula and the trocar are now side by side in the subxyphoid insertion site. The cannula can be advanced, withdrawn and manipulated very easily from the outside of the abdominal cavity.

2. Placing the Cannula in the Biliary Tree

An ENDODISSECT* Instrument or an atraumatic grasper is inserted via the subxyphoid trocar and grasps the tip of the cystic duct cannula. It is inserted into the cystic duct under direct vision and advanced into the common bile duct.

We routinely advance the cannula for about 5-6 cm, and then withdraw the cannula to leave approximately 1.5 to 2 cm inside the cystic duct.

3. Securing the Cannula in the Cystic Duct

The ENDO DISSECT*or grasper is removed from the intraabdominal cavity and replaced with the ENDO CLIP* Applier. It is essential to use a USSC ENDO CLIP* or a SURGICON applier. They are the only instruments that will allow the performance of the next maneuver.

Two clips are placed on the cystic duct. It is essential NOT to close the entire clip around the cystic duct so as not to entirely obliterate the duct and cannula. The partial closing of the clip can only be performed with the USSC ENDO CLIP* applier. ( The Ethicon clip Applier does not have this capability.) Another clip is tightly placed behind the cannula. If using the SURGICON clip applier, only one clip is used on the cannula and behid it.

The ENDO CLIP* applier is now replaced with the ENDO DISSECT* Grasper. The Cannula is grasped outside the cystic duct and pulled .5 cm to check that the cannula is not crushed or locked onto the cystic duct. Then additional cannula is inserted into the intraabdominal cavity to provide slack, so it can be placed laterally to allow for the completion of the laparoscopic cholecystectomy. A Blake Drain is inserted at the end of the procedure.

An intraoperative cholangiogram can be performed. If negative, the cannula is removed. We routinely do not perform an intraoperative cholangiogram. We order it a few hours after the procedure.

POST-OP ERCP

SCENARIO 1: CHOLEDOCHOLITHIASIS IS DEMONSTRATED ON THE TRANSCYSTIC CHOLANGIOGRAM: AN ERCP IS PLANNED.

ERCP Technique

The cystic duct catheter provides a portal through which a guidewire can be directed into the duodenum at the time of ERCP. The ability to place a guidewire greatly facilitates cannulation of the CBD during ERCP, especially in technically difficult cases.

Equipment

Pentax ERCP scope

Microvasive Ultratome XL

Zebra wire

Balloon Retrieval Catheters–8.5 mm. and 11 mm.(Microvasive Extractor XL)

Stone retrieval basket

Technique

STEP 1. A cholangiogram is first performed via transcystic catheter. This helps identify CBD and facilitates cannulation of papilla.

STEP 2. ERCP is then performed in the standard fashion.

STEP 3. If cannulation takes longer than 15 minutes, then a 400 cm Zebra wire is advanced through the transcystic catheter and directed by fluoroscopy into the CBD and through the papilla.

STEP 4. The endoscopist passes a snare through the biopsy channel of the ERCP scope, snares the end of the Zebra wire, and pulls it out of the scope.

STEP 5. The papillotomy is flushed with saline and advanced over the wire, through the scope, and into position in the papilla and CBD.

STEP 6. Endoscopist performs papillotomy over the guidewire and removes guidewire/papillotomy assembly.

STEP 7. The duct is then swept with an 8.5 mm or 11 mm balloon or a stone retrieval basket to remove stone(s).

The transcystic cannula is removed by firmly pulling on it at the bedside or in the ERCP suite. The Blake drain is left in place and the patient is discharged. The Blake drain is then removed a few days later as an outpatient.

NOTE: There has beeo reported leak following this protocol. However, the Blake drains are left in place should a bile leak occur.

SCENARIO 2: NO COMMON BILE DUCT STONE DEMONSTRATED.

The Cannula is removed by exerting firm traction. The Blake Drain is left in place and removed 48 hours later as an outpatient.

Advantages

This technique offers many advantages over existing strategies for dealing with CBD stones. First, ERCP’s will be limited only to those patients who have a stone visualized on transcystic cholangiogram. For those surgeons or gastroenterologists who currently stratify patients’ need for ERCP according to preoperative risk factors for CBD stones, the TCC approach will eliminate the need to perform ERCP on up to 80% of patients with positive risk factors but who have no stones (False Positives). The ERCP associated complications will thereby be eliminated. Second, the 15% risk of postoperative ERCP failure to cannulate or clear stones (even up to 10% in biliary referral centers) will be largely eliminated by the ability to place a transcystic, transpapillary guidewire. This safety valve will greatly facilitate endoscopic access to the bile duct, eliminate the need for a risky precut papillotomy to gain access to the CBD, and reduce the potential need for a second operation in patients in whom ERCP was a technical failure. Third, the TCC should eliminate the need for IOC and CBDE. Since the TCC/ERCP technique reduces the risks associated with ERCP and optimizes the chance of a successful outcome, the need for IOC and /or CBDE (laparoscopic or open) is greatly reduced (including those CBDE’s done for false positive IOC’s). Fourth, if this technique is applied to all laparoscopic cholecystectomies, then all CBD stones will be detected including up to 8% of patients who have no preoperative risk factors for stones.

References

1. Hopkins HH: Optical principles of the endoscope, in Berci G (ed): Endoscopy. New York: Appleton-Century-Crofts, 1976, p 3.

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