Lesson 6
MODERN SURGICAL TRAUMA IN TERMS OF MASS DAMEGE IN DISASTERS AND EMERGENCIES. FIGHTING SURGICAL TRAUMA .
Cardiopulmonary resuscitation (CPR) is an emergency first aid procedure for a victim of cardiac arrest. It is part of the chain of survival, which includes early access (to emergency medical services), early CPR, early defibrillation, and early advanced care. It is also performed as part of the choking protocol if all else has failed. It can be performed by trained laypersons or by health care or emergency response professionals. It is normally begun on an unbreathing unconscious person and continued until the underlying cause can be identified and a pulse is restored. CPR consists of chest compressions and rescue breaths (i.e. artificial blood circulation and lung ventilation) and is intended to maintain a flow of oxygenated blood to the brain and the heart, thereby extending the brief window of opportunity for a successful resuscitation without permanent brain damage
Many countries have official guidelines on how CPR should be provided, and these naturally override the general description of CPR in this article.
In 2005, new CPR guidelines were published with input from International Resuscitation Councils, and was agreed at the 2005 International Consensus Conference on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science. The primary goal was to simplify CPR for lay rescuers and healthcare providers alike to maximise the potential for early resuscitation. The important changes for 2005 are as follow.
A universal compression-ventilation ratio (30:2) is recommended for all single rescuers of infant (less than one year old), child (1 year old to puberty), and adult (puberty and above) victims (excluding newborns). The only difference between the age groups is that with adults the rescuer uses two hands for the chest compressions, while with children it is only one, and with infants only two fingers (pointer and middle fingers). It is worth noting that paediatric guidelines for healthcare professionals differ from the 30:2 compression-ventilation ratio stated here.
Lay rescuers do not need to assess for pulse or signs of circulation for an unresponsive adult victim.
Lay rescuers do not need to provide rescue breathing without chest compressions for an adult victim.
As research has shown that lay personnel cannot accurately detect a pulse in about 40% of cases and cannot accurately discern the absence of pulse in about 10%, the pulse check step has been removed from the CPR procedure completely for lay persons and de-emphasized for healthcare professionals.
Cardiac arrest and the place of CPR
The medical term for the condition in which a person’s heart has stopped is cardiac arrest (also referred to as cardiorespiratory arrest). CPR appropriate for cardiac arrest. If the patient still has a pulse, but is not breathing, this is called respiratory arrest and rescue breathing is more appropriate.
However, since people often can’t tell the difference (can’t accurately feel a pulse to determine whether the heart is still beating), CPR is often recommended for both.
The most common cause of cardiac arrest outside of a hospital is ventricular fibrillation (VF), a potentially fatal arrhythmia that is usually (but not always) caused by a heart attack. Other causes of cardiac arrest include drowning, drug overdose, poisoning, electrocution.
Sudden cardiac arrest is a leading cause of death, approximately 250,000 per annum outside a hospital setting in the USA. CPR can double or triple the victim’s chances of survival when commenced immediately. According to American Heart Association, only two thirds of victims of a witnessed cardiac arrest are administered CPR. Rapid access to defibrillation is also vital.
Blood circulation and lung ventilation are absolute requirements in transporting oxygen to the tissues. The brain may sustain damage after four minutes and irreversible damage after about seven minutes The heart also rapidly loses the ability to maintain a normal rhythm. Low body temperatures as seen in drownings prolong the time the brain survives. Following cardiac arrest, effective CPR enables enough oxygen to reach the brain to delay brain death, and allows the heart to remain responsive to defibrillation attempts.
CPR is taught to the general public because they are the only ones present in the crucial few minutes before emergency personnel are available. Simple training is the goal of the 2005 guidelines to maximise the prospect that CPR will be performed successfully.
Effectiveness
CPR is almost never effective if started more than 15 minutes after collapse because permanent brain damage has probably already occurred, especially if the person has stopped breathing, since the brain can only survive for 4-6 minutes without oxygen.[citation needed] A notable exception is cardiac arrest occurring in conjunction with exposure to very cold temperatures. Hypothermia seems to protect the victim by slowing down metabolic and physiologic processes, greatly decreasing the tissues’ need for oxygen.[citatioeeded] There are cases where CPR, defibrillation, and advanced warming techniques have revived victims after substantial periods of hypothermia.
Used alone, few patients will make a complete recovery, and those that do survive often develop serious complications. Estimates vary, but many organizations[citatioeeded] stress that CPR does not “bring anyone back,” it simply preserves the body for defibrillation and advanced life support. However, in the case of “non-shockable” rhythms such as Pulseless Electrical Activity (PEA), defibrillation is not indicated, and the importance of CPR rises. On average, only 5%-10% of people who receive CPR survive. The purpose of CPR is not to “start” the heart, but rather to circulate oxygenated blood, and keep the brain alive until advanced care (especially defibrillation) can be initiated. As many of these patients may have a pulse that is unpalpable by the layperson rescuer, the current consensus is to perform CPR on a patient that is not breathing. A pulse check is not required in basic CPR since it is so often missed when present, or even felt when absent, even by health care professionals
Studies have shown the importance of immediate CPR followed by defibrillation within 3–5 minutes of sudden VF cardiac arrest improve survival. In cities such as Seattle where CPR training is widespread and defibrillation by EMS personnel follows quickly, the survival rate is about 30 percent. In cities such as New York City, without those advantages, the survival rate is only 1-2 percent.
CPR is often severely misportrayed in movies and television as being highly effective in resuscitating a person who is not breathing and has no circulation. A 1996 study published in the New England Journal of Medicine showed that CPR success rates in television shows was 75%.
It is considered by a number of international bodies that in order for CPR to be effective, the guidelines must be simple and easy to remember.[citatioeeded]
CPR training
CPR is a practical skill and needs professional instruction followed up by regular practice on a resuscitation mannequin to gain and maintain full competency. Training is available through many commercial, volunteer and government organizations worldwide.
CPR training is not confined to the medical professionals. To be effective, CPR must be applied almost immediately after a patient’s heart has stopped. Early CPR on the scene of an incident is essential to the prevention of brain damage during a cardiac arrest. Blood flow and air supply to the brain and other major organs is maintained until a defibrillator and professional medical help arrives. Almost anyone is able to perform CPR with training, and health organizations advocate the development of CPR skills throughout the general public.
It is best to obtain training in CPR before a medical emergency occurs. One needs hands-on training by experts to perform CPR safely, and guidelines change, so that training should be repeated every one or two years. Training in first aid is often available through community organizations such as the Red Cross and St. John Ambulance. In many countries in the Commonwealth of Nations, St. John Ambulance and the Medic First Aid Organization provide CPR training. In Scotland, St. Andrew’s Ambulance Association provides first aid training. In the United States, the American Red Cross, American Heart Association and American CPR Training also offer CPR training. In addition, many employees at public areas or community centres are trained in CPR. Lifeguards are also trained in CPR and other first aid protocols.
In most CPR Classes a simple shortform is used for people to remember everything they need to do. The most common one used worldwide is DRABCD which stands for Danger, Response, Airway, Breathing, Compressions and Defibrillation.
History
CPR has been known in theory, if not practice, for many hundreds or even thousands of years; some claim it is described in the Bible, discerning a superficial similarity to CPR in a passage from the Books of Kings (II 4:34), wherein the Hebrew prophet Elisha warms a dead boy’s body and “places his mouth over his”. In the 19th century, doctor H. R. Silvester described a method (The Silvester Method) of artificial respiration in which the patient is laid on their back, and their arms are raised above their head to aid inhalation and then pressed against their chest to aid exhalation. The procedure is repeated sixteen times per minute. This type of artificial respiration is occasionally seen in movies made in the early part of the 20th century.
A second technique, described in the first edition of the Boy Scout Handbook in the United States in 1911, described a form of artificial respiration where the person was laid on their front, with their head to the side, and a process of lifting their arms and pressing on their back was utilized, essentially the Silvester Method with the patient flipped over. This form is seen well into the 1950s (it is used in an episode of Lassie during the Jeff Miller era), and was often used, sometimes for comedic effect, in theatrical cartoons of the time. This method would continue to be shown, for historical purposes, side-by-side with modern CPR in the Boy Scout Handbook until its ninth edition in 1979.
However it wasn’t until the middle of the 20th century that the wider medical community started to recognise and promote it as a key part of resuscitation following cardiac arrest. Peter Safar wrote the book ABC of resuscitation in
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Self-CPR
A form of “self-CPR” termed “Cough CPR” may help a person maintain blood flow to the brain during a heart attack while waiting for medical help to arrive and has been used in a hospital emergency room in cases where “standard CPR” was contraindicated. While this technique is not in widespread use, one researcher has recommended that it be taught broadly to the public However, the American Heart Association (AHA), does not endorse “Cough CPR”, which it terms a misnomer as it is not a recognized form of resuscitation. The AHA does recognize a limited legitimate use of the coughing technique:
This coughing technique to maintain blood flow during brief arrhythmias has been useful in the hospital, particularly during cardiac catheterization. In such cases the patient’s ECG is monitored continuously, and a physician is present.
“Cough CPR” was the subject of a hoax chain e-mail entitled “How to Survive a Heart Attack When Alone” which wrongly cited “ViaHealth Rochester General Hospital” as the source of the technique. Rochester General Hospital has denied any connection with the technique.
References
1. http://circ.ahajournals.org/cgi/content/full/112/24_suppl/IV-19
2. http://circ.ahajournals.org/cgi/content/full/112/24_suppl/IV-156
3. http://circ.ahajournals.org/cgi/content/full/112/22_suppl/III-5
The ABC Of Resuscitation
1. To check an unconscious victim, place two fingers under his chin and a hand on his forehead. Tilt his head back to open his airway. Remove any obstructions from his mouth.
2. Listen and feel for victim’s breathing. If he is breathing, place him in the recovery position. If he is not breathing, begin rescue breathing.
3. Check the victim’s circulation by feeling for a pulse at the side of his windpipe (carotid artery). If there is no pulse, begin CPR immediately.
Fig. Steps of resuscitation
The Recovery Position
1. If a victim is unconscious but breathing, bend his near arm up at a right angle to his body. Hold the back of his far hand to his near cheek. With the near leg straight, pull the far knee toward you.
2. With the victim on his side, place his uppermost leg at a right angles to his body. His head will be supported by the hand of the uppermost arm. Tilt his head back so that he will not choke if he vomits.
Fig. Position of patient during resuscitation
Rescue Breathing
1. To ensure an open airway, first clear the victim’s mouth of obstructions, then place one hand under his chin and one on his forehead, and tilt his head back.
2. Pinching the victim’s nose shut, clamp your mouth over his mouth, and blow steadily for about two seconds until his chest rises. Remove your mouth and let his chest fall, then repeat.
3. Listen for the victim’s breathing and check his pulse. If he still has a pulse, give 10 breaths per minute until help arrives or the victim is breathing by himself. If the pulse has stopped, combine rescue breathing with chest compressions.
Fig. First step of resuscitation
Cardiopulmonary Resuscitation (CPR)
If a person’s heart has stopped, give cardiopulmonary resuscitation (CPR). This consists of chest compressions to maintain the blood flow to the brain, combined with rescue breathing to oxygenate the blood. Give chest compressions at a rate of 80 per minute, counting “one-and-two-and…”
Fig. Artifitial lung ventilation
1. Place the heel of your hand two finger-widths up from the end of the sternum and your other hand on top of the first. Press down firmly, then release.
2. Check for a pulse. After 15 chest compressions, give the victim two breaths of rescue breathing. Repeat until the pulse restarts, professional help arrives, or you are too exhausted to continue.
Control of the airway is the single most important task for emergency resuscitation. If the patient has inadequate oxygenation or ventilation, inability to protect the airway due to altered sensorium from illness or drugs, or external forces compromising the airway (i.e., trauma), he or she may need advanced airway techniques as described in this chapter.
CPR is now a days is called as CPCR.
Cardiac arrest is defined as ‘inability of heart to sustain effective cardiac output, impairing tissue perfusion.
Cardiac arrest may be witnessed (monitored) or unwitnessed (unmonitored). It may be inside hospital or outside hospital.
Cardiac arrest may be of cardiac origin or non cardiac.
Cardiac arrest in adults is usually of cardiac origin and in children it is usually of respiratory origin and most common cause of arrest in adults is ventricular fibrillation.
Therefore unwitnessed cardiac arrest in adults should be considered due to ventricular fibrillation until proved otherwise and in children should be considered due to asystole until proved otherwise.
Rhythms in Cardiac Arrest
1. Ventricular fibrillation (or pulseless ventricular tachycardia) – most common rhythm.
2. Asystole – most common in children.
3. Electromechanical dissociation (pulse less electrical activity).
Management guidelines are based on the recent recommendation (2005) by American Heart Association (AHA) and Emergency Cardio Vascular care (ECC) with International Lesion Comittee on Resuscitation (ICCOR).
The management of CPR should be done in sequence A (Airway)—Breathing (B)—Circulation (C) and must be followed in these sequence.
Management of CPR is done under three heads:
1. Basic life support.
2. Advance life support.
3. Post resuscitation life support.
AHA and ECC have given 4 link chain of survival: 1. Early recognition and activation of emergency medical services.
2. Immediate CPR (every minute delay decreases prognosis by 7-10%).
3. Early shock (CPR + shock within 5 minutes has survival rate of 49-75%).
4. Early advance life support.
BASIC LIFE SUPPORT (BLS) (Primary A, B, C, D)
Basic life support includes:
1. Airway management (manual).
2. Breathing by mouth to mouth, mouth to nose or bag and mask ventilation.
3. Circulation by cardiac massage.
4. Deflbrillation by automatic external deflbrillator (AED): AED are the devices which automatically detects rhythm and give shock if rhythm is shockable. Since they detect rhythm automatically and gives shock automatically they can be used even by lay rescuer. (In manual defibrillators rescuer has to detect rhythm, therefore not included as basic life support as they can be used only by health personnel).
ADVANCE LIFE SUPPORT (ALS)
Advance life support includes:
1. Airway management by equipments like Guedel ‘s airway, laryngeal mask airway or endotracheal tube.
2. Breathing by advanced airways e. endotracheal tube, laryngeal mask, combitube or tracheostomy.
3. Circulation by cardiac massage.
4. Defibrillation by manual defibrillators.
5. Drugs.
AIRWAY MANAGEMENT
The most common cause of airway obstruction in unconscious patient is tongue fall ( e. tongue falling
Parameter Basic life support Advance life support
(Primary A,B,C,D) (Secondary A,B,C,D)
Airway management Manual With equipments like Guedel’s airway, endotracheal tube laryngeal mask airway (LMA) or tracheostomy tube.
Breathing Mouth to mouth, mouth to Advanced methods like endotracheal tube, LMA, nose or bag & mask combitube or tracheostomy tube.
Circulation Cardiac massage. Cardiac massage
Defibrillation Automatic external defibrillator Manual defibrillator
Drugs – back on posterior pharyngeal wall and obstructing the airway).
This tongue fall can be managed by:
A. Manually which includes:
Open mouth and clear airways (if something is clearly visible in oral cavity).
i Tilt head backwards ( e. neck extension) and chin lift. Jaw thrust e. mandible is pulled forward. In patients with cervical spine fracture head tilt and chin lift is C/I and airway should be managed only by jaw thrust
Airway insertion: Most commonly used in Guedel’s, other are Safar, nasopharyngeal, laryn-
geal mask airway (LMA),
C. Endotracheal tube: It is the most definitive method to maintain airway.
Management of Airway Obstruction Due to Foreign Body
1. Infant chest thrust: 4 blows given with thrust by heel of hand between the shoulders.
2. Back blows: 4 blows on the middle of back. Again performed for infants.
3. Heimlich manoeuvre: Manual thrust with the patient standing, rescuer behind the patient and compressing the abdomen 6 to 10 times. This method is for adults and older children.
4. Chest thrust (manual compression over lower sternum): Employed in very obese or pregnant patient where abdominal compression is not possible.
5. Finger sweep method: Possible in unconscious patients only.
6. Cricothyroidotomy: As a life saving procedure to secure airway.
Airway obstruction due to other causes like laryngeal edema, acute epiglottitis and laryngotracheobron-chitis may require tracheostomy.
BREATHING (Ventilation)
Breathing can be accomplished by:
1. Mouth to mouth:
Method: Open airway — pinch victim’s nose — create airtight seal — give breath over 1 sec with sufficient force to move chest (not excessive force) — provide 2nd breath in the same way if rescuer is hesitant in giving direct mouth to mouth he/she can use face shields/plastic or silicone sheets or even a handkerchief, if nothing is available.
2. M outh to airway: By Safar or Brook airway.
3. Bag and mask. Disadvantage of bag and mask
ventilation are:
Difficult and exhausting.
Increased dead space.
Increased chances of aspiration.
4. Ventilation by advanced methods:
Endotracheal tube: Intubation is most definitive and best method for ventilation. i Laryngeal mask airway, Combitube. Tracheostomy tube.
5. Ventilation by automatic ventilators.
CIRCULATION
This is accomplished by cardiac massage.
Method
It is done in supine position . But in very rare cases, where supine position is not possible it can be done in prone position also.
The rescuer stand (or bend on knee if the victim is on floor) on side (usually right side), lock one hand over other and provide compression over the lower third of sternum (2 fingers above xiphoid process).
The force generated during massage should be able to depress sternum by 114-
Patient should lie flat on hard surface.
Physiological Considerations of Cardiac Massage
Heart compressed between sternum and spine results in ejection of blood from heart (cardiac pump theory) but another convincing theory is thoracic pump theory which states that cardiac compression raises intrathoracic pressure forcing blood out of chest and dynamic venous compression preventing backward flow, heart acting only as a passive conduit.
Chest compression can generate a systolic BP of 80-100 mmHg but diastolic only 10-40 mmHg (which may compromise coronary flow). Effective cardiac output generated by successful massage is only 30% of normal. So all efforts to restore spontaneous cardiac activity should be started immediately.
Monitoring of CPR
1. Capnography: It is considered as most reliable and best Indicator to see the effectiveness of CPR. Successful cardiac massage should be able to produce ETCO2 of at least 20 mmHg and ETCO2 becoming normal (40 mmHg), is the earliest indicator of return of normal circulation.
2. Palpation of pulses (carotid): It is the most effective clinical monitor to see the effectiveness of cardiac massage. A successful cardiac massage should be able to generate a major peripheral pulse especially carotid.
3. Coronary perfusion pressure: Good guide but very difficult to measure.
COMPRESSION (C) TO VENTILATION (V) RATIO
Before advanced airway ( e. by mouth to mouth, bag and mask ventilation), the ratio should be 30:2 (30 compressions followed by 2 breaths)’irrespective of duration of resuscitation (previously this ratio was 15:2). The reason for change in ratio is to minimize interruption in chest compression (this is the most important goal of latest recommendations).
After advanced airway ( e. endotracheal tube, LM A or combitube): Compression will be continued at a rate of 100 compressions/minute and breathing at a rale of 8-10 breaths/min. with no synchronization e. no pause for ventilation. The aim is again same e. uninterrupted compressions. Previous ratio of 5:1 now is obsolete, rather ventilation rate should not exceed more than 12 breaths/min. as high rate (more ventilation will increase intrathoracic pressure which decreases venous return thereby decreasing cardiac output and hence coronary and cerebral perfusion). Therefore low tidal volume (6-7 ml/kg) is preferred over large tidal volume (10-12 ml/kg) and one breath should not exceed more than 1 second.
If there are 2 rescuers they should rotate after 2 minutes (or 5 cycles of 30:2) to avoid fatigue of one person providing compression (because studies have shown that after 2 minutes the performance of compression start decreasing because of fatigue), but this change over should not take more than 5 seconds.
Therefore it can concluded that key guidelines for present day CPR are (i) push hard ( ) push fast (Hi) allow full chest recoil and (iv) minimize interruption in chest compressions.
ADVANCED LIFE SUPPORT (Secondary ABCD)
As described earlier in advanced life support airway and ventilation are maintained by advance airway method and circulation by continuing cardiac massage, recognising arrhythmias and managing them by defibrillators and drugs or any other intervention done beyond basic life support is included in advance life support. Therefore advanced life support is employed in hospital arrest.
Airway management and ventilation employed in advance life support has been described in detail in chapter on instrument (chapter no. 6).
Defibrillation: Done for ventricular fibrillation, pulseless ventricular tachycardia and polymorphic ventricular tachycardia.
Defibrillators have been classified as: Monophasic (delivers current of one polarity only)
and biphasic (delivers current of two polarities), Manual or automatic (AED).
Biphasic are considered superior to monophasic and that is why most of the defibrillators which are manufactured today are biphasic.
POSITION OF DEFIBRILLATION PADDLES
The ideal position would be like that the heart is sandwiched between paddles e., one is placed anteriorly at the precordial region and second one posteriorly but this is not possible because patient lies supine so usually
Paddle size
• For adults:
• For children:
• For infants :4.5cm.
Latest Recommendations for Energy selection and shock protocol.
1. Contrary to previous recommendation of 3 successive shocks (200,300 & 360 J) now a days Only Single Shock of 360J by monophasic defibrillators, and 150-200J withbiphasic [biphasic 150-200J is equivalent to 360 J of monophasic) is given.
2. Immediately after giving shock, give 5 cycles of 30:2 (without advance airway) or 2 minutes of CPR (with advance airway) before checking rhythm [Earlier rhythm was checked just after giving shock]. The rationale for this recommendation is that it actually takes around 2 minutes for heart to recover completely after ventricular fibrillation so CPR during this 2 minutes is required to maintain coronary and cerebral perfusion.
So the protocol for advance life support maybe in continuation of basic life support (where BLS is provided by lay rescuers/paramedicals) or fresh management in hospital arrest.
Consider termination of efforts if there is no response after 20 minutes.
MANAGEMENT OF PULSELESS ELECTRIAL ACTIVITY AND ASYSTOLE
PULSELESS ELECTRICAL ACTIVITY (PEA)
Also called as electromechanical dissociation (EMD). It is the condition in which peripheral pulses are not palpable but heart shows some electrical activity on ECG other than ventricular tachycardia and ventricular fibrillation.
Causes are
1. Hypovolemia (most common cause).
2. Cardiac tamponade.
3. Tension pneumothorax.
4. Pulmonary embolism.
5. Hypoxia.
6. Hyperkalemia.
7. Hypothermia.
8. Acidosis.
9. Overdosage of digitalis, (5 blockers, calcium channel blockers.
(Conditions 6 to 9 show idioventricular rhythm).
Treatment
Treatment of PEA lies in treating the cause, adrenaline
PROTOCOL FOR ADVANCED LIFE SUPPORT
Assess responsiveness
Call for help (Activate EMS)
Manage airway and breathing8
Asses circulation -> if present give breaths at a rate of 10-12/min
Absent
Start
CPR with compression rate of 100/min and ventilation with 8-10 breath/min
with advance airway and 30:2 without advance airway
a. whenever possible defibrillation should precede intubation and IV access (should not delay defibrillation if ventilation is achieved without intubation, like bag & mask)
Assess Rhythm
Shockable (VF, pulseless V tachy)
1. Give one shock (360 J with monophasic & 200 J with biphasic)
Continue CPR for 2 min (or 5 cycles of 30:2 if airway is still not maintained by advance methods)
Check Rythm
Still shockable rhythm
I Shockable
Recovered
Rhythm becomes
non shockable
Stop CPR
(Asystole)
Non shockable (Asystole, PEA)
Continue CPR
Adrenaline 1 mg IV and repeat every 3-5 minutes (if IV access not possible than use intraoss-eous or endotracheal route) Consider vasopressin 40U after 1st or 2nd dose of adrenaline Atropine 1 mg, repeat every 3-5 minutes (to a max. of 3 doses) Keep on checking rhythm every 2 min, if non shockable, continue same treatment and if becomes shockable treat like shockable.
2. • Continue CPR ~~* • Give adrenaline (1:10,000) 1 mg IV, endotracheal or Intraosseous
Give shock (again 360 J with monophasic & 200 J with biphasic)
Continue CPR for 2 min.
Check rhythm
Still shockable
Recovered
Non shockable
3. • Continue CPR
• Repeat adrenaline 1 mg or vasopressin 40 U (as an alternative to adrenaline)
1 Shock (360 J – Monophasic, 200 J – Biphasic)
Continue CPR for 2 minutes 1
• Continue CPR
• Give amiodarone / gnocaine / magnesium sulphate
Shock (with 360 J – monophasic with 200 J biphasic)
• Proceed like non shockable
I
Recovered
Shockable
Go back to stage 2 and continue same protocol
Non shockable
Treat like non shockable and pacing as immediate measures to tide over the crisis.
MANAGEMENT OF ASYSTOLE
Asystole is the terminal event of all arrhythmias.
Management
Intubate immediately and start pulmonary ventilation and cardiac massage
Consider possible causes like hyperkalemia, hypokalemia, hypothermia, hypoxia, acidosis,
I Adrenaline 1 mg IV and repeat every 3 minutes Vasopressin 40 Units after 1s’ or 2nd dose of adrenaline Atropine 1 mg IV and repeat every 3 minutes to a total of 0.04 mg/kg Transcutaneous pacing
No response Consider termination of efforts
PAEDIATRIC CPR (excluding NEWBORN)
Age classification: From CPR point of view.
• Neonate: First 4 weeks after birth.
• Infants: 4 weeks to I year.
• Child: 1-14 years (previously children were considered 1 -8 years) for medical staff but for lay rescuers children still mean 1-8 years.
• Adults: > 14 years for medical staff. > 8 years for lay rescuers.
Differences from Adults
• Ratio of compression to breathing without advance airway: 30:2 for one rescuer and 15:2 for 2 rescuers. (While for adults it is 30:2 irrespective of rescuers).
• With Advance airway: 100 compressions per minute (even for infants which was earlier 120/min) with 8-10 breaths/min. and unsynchronized e. no pause for ventilation (similar to adults) [contrary to previous 5:1 ratio and synchronized].
• If pulses are palpable then give breath at a rate of 12-20/min (Adults 10-12/min).
• Pulse check:
– Infants: Brachial/Femoral.
– Children: Carotid.
– Adult: Carotid/Femoral.
• In emergency cuffed tubes can be used in paediatric age group if inflation pressure is less than 20 cmH20.
• If heart rate is <60/min with signs of poor prfusion (pallor/cyanosis) start compressions.
• Cardiac arrest in children is not usually because of ventricular fibrillation and cause is usually asphyxial (respiratory) so the difference from adults in protocol of basic life support is that after assessing responsiveness immediately start CPR and give five cycle of30:2 and then call for Emergency medical system (EMS) while in adults (see algorithm for BLS) first step after assessing responsiveness is activation of EMS and than start CPR, further protocol for BLS remains same.
• Advance life support protocol for paediatric patient remains same with some differences like:
1. Energy selection for shock (manual) is 2 J/kg for first shock and 4 J/kg subsequently. If AED is used it automatically select energy and do attenuation accordingly. Paediatric AED are only recommended for children < 8yrs (or <
2. Another important difference from adults in management of asytole is that atropine and
vasopressin are not recommended for paediatric age group.
3. Endotracheal concentration of adrenaline for adults is 1:10,000 but for paediatric 1 : 1000.
NEWBORN CPR
The detailed discussion of newborn CPR is beyond the scope of this book but some of the notable differences are:
1, Rate of ventilation (breathing) is 40-60 breaths/ min (if only ventilation is given).
2. The primary measure for successful ventilation is increase in heart rate.
3. Indication of chest compression is HR (Heart rate) < 60/min. inspite of adequate ventilation with 100% oxygen for 30 seconds.
4. 2 thumbs with encircled chest is preferred method for compression over only 2 thumb technique.
5. Compression ventilation ratio is 3:1 (90 compression with 30 breaths) and synchronized.
6. Reassessment to be made every 30 sec. and continue compression till HR > 60/min.
7. Adrenaline indicated if HR < 60 /min.
8. Stop resuscitation if no signs of life after 10 minutes.
Lay Rescuers
1. Pulse check not expected from them therefore they can start compression even if not able to palpate pulse of an unresponsive victim.
2. Paediatric means 1-8 years (for health care professionals pead. means 1-14 years).
CPR IN PREGNANCY
1. External cardiac massage should be combined with lateral tilt.
2. Sodium bicarbonate administration is advocated early.
3. Early insertion of endotracheal tube (as pregnant patients are very vulnerable for aspiration) therefore during mask ventilation continously apply cricoid pressure till patient is intubated.
4. More prone for hypoxia so use high FIO2.
5. Chest compression should be performed harder.
6. Emergency LSCS (cesarean section) should be considered only if:
– Fetus > 25 week.
– Uterine decompression is mandatory for patients life (fetus can be saved only if LSCS is performed within 5 min. of arrest).
OPEN CHEST MASSAGE
Indications are:
1. Cardiac tamponade.
2. Penetrating blunt trauma.
3. Air embolism.
4. Arrest during intrathoracic procedures.
5. Chest deformities.
COMPLICATIONS OF CPR
1. Rib fracture.
2. Pneumothorax.
3. Pneumopericardium.
4. Pneumomediastinum.
5. Injury to diaphragm.
6. Gastric injury.
7. Lung injury.
8. Injury to major vessels particularly by fractured rib.
9. Injury to abdominal organs: Liver, spleen and stomach.
OUTCOME OF CPR
Depends on the:
1. Cause.
2. ThetimeofinitiationofCPRand
3. Duration for which CPR is performed.
Survival is better, if basic life support (BLS) is
initiated within 4 minutes of arrest and ALS within 8 minutes.
Fortunately most common cause of cardiac arrest is ventricular fibrillation which if detected in time can have 50 to 60% success rate. Average survival rate of in hospital arrest is 8 to 21 %. Survival is better if arrest time (onset of arrest to start of CPR) is less than 6 minutes and CPR time (time required for successful CPR) is less than 30 minutes.
NEWER TECHNIQUES OF CPR
1. Simultaneous abdominal compression: Limits
caudal movement of diaphragm and limits dissipation of intrathoracic pressure.
2. Vest CPR: Increasing intrathoracic pressure by physically inflating the bladder around chest.
3. Simultaneous ventilation with every compression.
4. Cardiopulmonary bypass.
5. Cough CPR (applicable to conscious patient having VF): If a patient cough during VF, increase in intrathoracic pressure can maintain cerebral (perfusion ( e. consciousness) for 90 sec. So ask him to cough every 1-3 sec. till he/she is defibrillated.
6. High frequency (120/min) CPR: Not better than standard CPR.
INITIAL APPROACH
The initial approach to airway management is simultaneous assessment and management of the adequacy of airway patency (the A of ABCs) and oxygenation and ventilation (the B of ABCs).
1.
The patient’s color and respiratory rate must be assessed; marked hypoventilation with or without cyanosis may be an indication for immediate intubation.
2.
The airway should be opened with head tilt–chin lift maneuver (jaw thrust should be used if C-spine injury is suspected). If needed, the patient should be bagged with the bag-valve-mask device, including an O2 reservoir. For a good seal, the proper size mask should be ensured. This technique may require an oral or nasal airway or two rescuers to both seal the mask (two hands) and bag the patient.
3.
The patient should be placed on a cardiac monitor, pulse oximetry, and possibly capnography (end-tidal CO2), while the remaining vitals, pulse, and blood pressure (temperature is important but can be delayed to assure the ABCs) can be collected.
4.
The need for invasive airway management techniques must be determined as described later. It is essential to not wait for arterial blood gas analyses (ABG) if the initial assessment declares the need for invasive airway management. If the patient does not require immediate airway or ventilation control, he or she should be administered oxygen by face mask, as necessary, to assure an O2 saturation of 95%. Laboratory studies should be collected as needed. Do not remove a patient from oxygen to draw an ABG unless deemed safe from the initial assessment.
OROTRACHEAL INTUBATION
The most reliable means to ensure a patent airway, prevent aspiration, and provide oxygenation and ventilation is endotracheal (ET) intubation. Many conscious patients require intubation (see the section, “Rapid Sequence Induction” later). Selection of the blade should be considered in advance, if possible. The curved blade rests in the vallecula above the epiglottis and indirectly lifts it off the larynx because of traction on the frenulum. The straight blade is used to lift the epiglottis directly. The curved blade does a better job of clearing the tongue from view and may be less traumatic and reflex-stimulating. The straight blade is mechanically easier to insert in many patients.
Emergency Department Care and Disposition
1.
Adequate ventilation must be ensured while the equipment is prepared. The patient should be preoxygenated, with or without a bag-valve-mask device, depending on the clinical need. Vital signs must be monitored and pulse oximetry used throughout the procedure.
2.
The blade type and size (usually #3 or #4 curved blade, or #2 or #3 straight blade) should be selected; the blade light should be tested. The tube size (usually 7.5 to
3.
The patient should be positioned with the head extended and neck flexed, possibly with a rolled towel under the occiput. If C-spine injury is suspected, the head or neck should not be moved. Rapid sequence induction with in-line traction, nasotracheal intubation, or cricothyrotomy should be considered.
4.
The blade should be inserted on the right and slowly advanced in search of the epiglottis. The patient should be suctioned as necessary. If the curved blade is used, the tip should be slid into the vallecula and lifted (indirectly lifting the epiglottis); if a straight blade is used, the epiglottis should be lifted directly in the direction the handle points, that is, 90° to the blade. It is important to not rock back on the teeth.
5.
Once the vocal cords are visualized, it is important to not lose sight of them. The assistant should be asked to place the tube in the physician’s hand. Pass the tube between the cords, avoiding force. The stylet should be removed, the balloon cuff inflated. Ventilate the patient with a bag-valve device and check for bilateral breath sounds. Placement should be confirmed with an end-tidal CO2 detector (not reliable if the patient is in cardiac arrest) or capnography. Tube length should be checked; the usual distance (marked on the tube) from the corner of the mouth to
6.
The tube should be taped in place and a bite block inserted. Correct intubation and tube placement can be verified with a portable chest x-ray.
7.
If unsuccessful, reoxygenation should be performed with bag-valve-mask device. The technique can be changed by possibly using a smaller tube, different blade type or size, or repositioning the patient and reattempting intubation.
Short-term complications from orotracheal intubation (trauma to surrounding structures) are unusual, as long as correct position is confirmed. Failure to confirm position immediately can result in hypoxia and neurologic injury. Endobronchial intubation is usually on the right side and is corrected by withdrawing the tube
NASOTRACHEAL INTUBATION
Nasotracheal intubation is indicated in situations where laryngoscopy is difficult, neuromuscular blockade is hazardous, or crico-thyrotomy unnecessary. Severely dyspneic, awake patients with congestive heart failure, chronic obstructive pulmonary disease, or asthma often cannot remain supine for other airway maneuvers but do tolerate nasotracheal intubation in the sitting position. Relative contraindications for this technique include complex nasal and massive midface fractures and bleeding disorders.
Emergency Department Care and Disposition
1.
Both nares should be sprayed with a topical vasoconstrictor and anesthetic. Between 4 to 10% cocaine solution is an appropriate single agent, but may cause unwanted systemic cardiovascular effects. Topical neosynephrine is an effective vasoconstrictor, and tetracaine is a safe effective topical anesthetic.
2.
The tube size must be chosen, usually between 7.0 to
3.
The largest nares should be used or the right side if the nares are equal. Some operators recommend dilating the nares with a lubricated nasal airway. The patient may be sitting up or supine.
4.
An assistant can immobilize the patient’s neck. The physician should stand to the patient’s side, with one hand on the tube and with the thumb and index finger of the other hand straddling the larynx. The tube should be advanced slowly, with steady gentle pressure. The tube should be twisted to help move past obstructions in the nose and nasopharynx. The tube should be advanced until
maximal airflow is heard through the tube; this means the larynx is now close by.
5.
The physician should listen carefully to the rhythm of inspiration and expiration. The tube should then be gently but swiftly advanced during the beginning of inspiration. Entrance into the larynx may initiate a cough, and most expired air should exit the tube even though the cuff is uninflated. If the tube is foggy the cuff should be inflated.
6.
If intubation is unsuccessful, the physician should carefully look for a bulge lateral to the larynx (usually the tip of the tube is in the pyriform fossa on the same side as the nares used). If found, the tube must be retracted until maximal breath sounds are heard and then intubation should be reattempted by manually displacing the larynx toward the bulge. If no bulge is seen, it is possible that the tube has gone posteriorly into the esophagus. In this case, the tube should be withdrawn until maximal breath sounds are heard. Intubation should again be reattempted after the patient’s head is extended and a Sellick’s maneuver performed. Another option is to use a directional control tip (Endotrol) or fiberoptic laryngoscope. The head should not be moved if C-spine injury is suspected.
Complications other than local bleeding are rare. Occasionally, marked bleeding will prompt the need for orotracheal intubation or cricothyrotomy.
CRICOTHYROTOMY
Indications for immediate cricothyrotomy include severe, ongoing tracheobronchial hemorrhage, massive midface trauma, and inability to control the airway with the usual less-invasive maneuvers. Cricothyrotomy is relatively contraindicated in patients with acute laryngeal disease due to trauma or infection or recent prolonged intubation and should not be used in children below the age of 12.
Emergency Department Care and Disposition
1.
Sterile technique should be used. The cricothyroid membrane should be palpated with digital stabilizion of the larynx (see With a #11 scalpel, a vertical 3 to
2.
The membrane should be repalpated and a horizontal stab should be made through its inferior aspect. The blade should be kept temporarily in place.
3.
The larynx should be stabilized by inserting the tracheal hook into the cricothyroid space and retracting upon the inferior edge of the thyroid cartilage (an assistant should hold after the hook is placed). Leaving the blade tip in the space, a slightly open hemostat should be inserted straddling the blade and spread open horizontally.
4.
The scalpel should be removed and a dilator inserted (LaBorde or Trousseau). The tracheal hook can then be removed.
5.
A #4 Shiley tracheostomy tube should be introduced (or the largest tube that will fit). Alternatively, a small cuffed endotrachial tube may be used (#6 or the largest tube that will fit). The balloon should be inflated and the tube secured in place.
6.
The physician should check for bilateral breath sounds. Make sure subcutaneous air is not introduced. Placement can be checked with an end-tidal CO2 detector and chest x-ray.
RAPID SEQUENCE INDUCTION
Complex airway emergencies in select nonfasted patients may require rapid sequence induction. This technique couples sedation to induce unconsciousness (induction) with muscular paralysis. Intubation follows laryngoscopy while maintaining cricoid pressure to prevent aspiration. The principle contraindication is any condition preventing mask ventilation or intubation.
1.
The cardiac monitor, oximetry, and capnography should be set up, if available. Equipment should be checked.
2.
The patient should be preoxygenated with 100% oxygen.
3.
Lidocaine (1.5 mg/kg intravenously) should be considered in a head trauma patient to prevent increased intracranial pressure. Atropine (0.4 mg/kg intravenously) should be considered to prevent reflex bradycardia, but is not essential.
4.
Medication for sedation or analgesia should be considered, if such agents are not being used for induction.
5.
A defasciculating dose of a nondepolarizing agent (i.e., vecuronium at 0.02 mg/kg) is used if succinylcholine is given for paralysis.
6.
The patient should be induced with thiopental (3 to 5 mg/kg), methohexital (1 to 2 mg/kg), or midazolam (0.1 mg/kg with 5 mg maximum dose). Barbiturates should not be used in a patient with hypotension or reactive airway disease (caution in head injury). Benzodiazepines may be inadequate for induction, however, midazolam is an excellent amnestic agent. Etomidate, 0.3 mg/kg, is an excellent alternative in a hypotensive patient. Ketamine, 1 to 2 mg/kg, should be considered for the induction of a patient who has active bronchospasm for its bronchodilator properties.
7.
In a patient needing analgesia in addition to sedation, opiates should be considered for induction. These agents are reversible with naloxone. Fentanyl, 2 to 10 μg/kg, is commonly used.
8.
Cricoid pressure should be applied before paralysis and maintained until intubation is accomplished.
9.
Succinylcholine (1.0 mg/kg) is chosen for paralysis in many cases because of its rapid onset and short duration of action; it should not be used in a patient with preexisting paralysis or > 2 h after severe burns, as hyperkalemia may occur. A nondepolarizing agent such as vecuronium (0.2 mg/kg) may be chosen for a patient with increased intracranial pressure, one in status asthmaticus, or at operator discretion.
10.
The trachea should be intubated and cricoid pressure released.
11.
The physician should be prepared to bag the patient if intubation proves unsuccessful. Invasive airway techniques should be considered as indicated.
Alternative drugs for rapid sequence induction are listed in Chap. 15 of Emergency Medicine, A Comprehensive Study Guide, 5th ed. Airway management alternatives to the methods described earlier include retrograde tracheal intubation, translaryngeal ventilation, digital intubation, transillumination, fiberoptic assistance, and formal tracheostomy. Translaryngeal ventilation may be used to temporarily provide ventilation until a more definitive procedure is possible. When oral intubation is indicated but has been unsuccessful, and the patient can be temporarily ventilated with a bag-valve-mask unit, the following assist methods are warranted. Retrograde tracheal intubation, digital intubation, transillumination, or fiberoptic assistance may be helpful. Formal tracheostomy is reserved for those experienced in the technique when less-invasive or more-rapid methods (cricothyrotomy) are unsuccessful.
2 Dysrhythmia Management
Emergency Medicine Companion Handbook
If sustained junctional escape rhythms are producing symptoms, the underlying cause should be treated. Atropine can be used to accelerate temporarily the sinus node discharge rate and enhance AV nodal conduction.
VENTRICULAR DYSRHYTHMIAS
Aberrant Versus Ventricular Tachydysrhythmias
Differentiation between ectopic beats of ventricular origin and those of supraventricular origin that are conducted aberrantly, can be difficult, especially in sustained tachycardias with wide QRS complexes (WCT). In general, the majority of patients with WCT have ventricular tachycardia, which should be approached as ventricular tachycardia, until proved otherwise. Several guidelines follow:
1.
A preceding ectopic P wave is good evidence favoring aberrancy, although coincidental atrial and ventricular ectopic beats or retrograde conduction can occur. During a sustained run of tachycardia, AV dissociation favors a ventricular origin of the dysrhythmia.
2.
Postectopic pause: A fully compensatory pause is more likely after a ventricular beat, but exceptions occur.
3.
Fusion beats are good evidence for ventricular origin but, again, exceptions occur.
4.
A varying bundle branch block pattern suggests aberrancy.
5.
Coupling intervals are usually constant with ventricular ectopic beats, unless parasystole is present. Varying coupling intervals suggest aberrancy.
6.
Response to carotid sinus massage or other vagal maneuvers will slow conduction through the AV node and may abolish reentrant SVT and slow the ventricular response in other supraventricular tachydysrhythmias. These maneuvers have essentially no effect on ventricular dysrhythmias.
7.
A QRS duration of longer than 0.14 s is usually found in ventricular ectopy or tachycardia.
8.
Historical criteria also have been found to be useful: a patient over 35 years old or a history of MI, CHF, or coronary artery bypass graft strongly suggest ventricular tachycardia in patients with WCT.
Emergency Department Care and Disposition
1.
As with ventricular tachycardia lidocaine 1 to 1.5 mg/kg intravenously should be started and may be repeated up to 3 mg/kg.
2.
Adenosine 6 mg intravenously may be tried prior to procainamide (see ventricular tachycardia management later for administration guidelines).
Premature Ventricular Contractions
Clinical Features
Premature ventricular contractions (PVCs) are due to impulses originating from single or multiple areas in the ventricles. The ECG characteristics of PVCs are (a) a premature and wide QRS complex; (b) no preceding P wave; (c) the ST-segment and T wave of the PVC are directed opposite the major QRS deflection; (d) most PVCs do not affect the sinus node, so there is usually a fully compensatory postectopic pause, or the PVC may be interpolated between 2 sinus beats; (e) many PVCs have a fixed coupling interval (within 0.04 s) from the preceding sinus beat; and (f) many PVCs are conducted into the atria, producing a retrograde P wave .
FIG. 2-11 Premature ventricular contractions (PVCs). A. Unifocal PVC. B. Interpolated PVC. C. Multifocal PVCs.
PVCs are common, occur in most patients with ischemic heart disease, and are universally found in patients with acute MI. Other common causes of PVCs include digoxin toxicity, CHF, hypokalemia, alkalosis, hypoxia, and sympathomimetic drugs.
Emergency Department Care and Disposition
1.
Most acute patients with PVCs will respond to intravenous lidocaine (1 mg/kg intravenously), although some patients may require procainamide. Although single studies have suggested benefit, pooled data and meta-analysis find no reduction in mortality from either suppressive or prophylactic treatment of PVCs.
Accelerated Idioventricular Rhythm
Clinical Features
The ECG characteristics of accelerated idioventricular rhythm (AIVR) are (a) wide and regular QRS complexes; (b) rate between 40 and 100, often close to the preceding sinus rate; (c) most runs of short duration (3 to 30 beats); and (d) an AIVR often beginning with a fusion beat. This condition is found most commonly with an acute MI.
FIG. 2-12 Accelerated idioventricular rhythms (AIVRs).
Emergency Department Care and Disposition
1.
Treatment is not necessary. On occasion, AIVR may be the only functioning pacemaker, and suppression with lidocaine can lead to cardiac asystole.
Ventricular Tachycardia
Clinical Features
Ventricular tachycardia is the occurrence of 3 or more beats from a ventricular ectopic pacemaker at a rate greater than 100. The ECG characteristics of ventricular tachycardia are (a) wide QRS complexes; (b) rate greater than 100 (most commonly 150 to 200); (c) usually regular rhythm, although there may be some beat-to-beat variation; and (d) usually constant QRS axis
FIG. 2-13 Ventricular tachycardia.
Ventricular tachycardia is rare in patients without underlying heart disease. The most common causes of ventricular tachycardia are ischemic heart disease and acute MI. Ventricular tachycardia cannot be differentiated from SVT with aberrancy on the basis of clinical symptoms, blood pressure, or heart rate. Patients who are unstable should be cardioverted, which is effective for both dysrhythmias. In general, it is best to treat all wide complex tachycardias as ventricular tachycardia with lidocaine or procainamide. Adenosine appears to cause little harm in patients with ventricular tachycardia and has potential merit for the treatment of wide QRS complex tachycardias.
Emergency Department Care and Disposition
1.
Unstable patients, or those in cardiac arrest, should be treated with synchronized cardioversion. Ventricular tachycardia can be converted with energies as low as 1 J, and over 90 percent can be converted with less than 10 J. ACLS guidelines recommend that pulseless ventricular tachycardia be defibrillated (unsynchronized cardioversion) with 200 J. Another alternative for unstable patients is intravenous amiodarone. (See treatment recommendations under ventricular fibrillation.)
2.
Clinically stable patients should be treated with intravenous antidysrhythmics.
a.
Lidocaine 75 mg (1.0 to 1.5 mg/kg) intravenously over 60 to 90 s can be administered, followed by a constant infusion at 1 to 4 mg/min (10 to 40 μg/kg/min). A repeat bolus dose of 50 mg lidocaine may be required during the first 20 min to avoid a subtherapeutic dip in serum level due to the early distribution phase.
b.
Procainamide can be administered intravenously at less than 30 mg/min until the dysrhythmia converts, the total dose reaches 15 to 17 mg/kg iormals (12 mg/kg in patients with CHF), or early signs of toxicity develop, with hypotension or QRS prolongation. The loading dose should be followed by a maintenance infusion of 2.8 mg/kg/h in normal subjects.
c.
Bretylium 500 mg (5 to 10 mg/kg) intravenously over 10 min can be administered, followed by a constant infusion at 1 to 2 mg/min.
Torsades de Pointes
Atypical ventricular tachycardia (torsade de pointes, or twisting of the points) is where the QRS axis swings from a positive to negative direction in a single lead (Fig. 2-14).
FIG. 2-14 Two examples of short runs of atypical ventricular tachycardia showing sinusoidal variation in amplitude and direction of the QRS complexes: “Le torsade de pointes” (twisting of the points). Note that the top example is initiated by a late-occurring PVC (lead II).
Drugs that further prolong repolarization—quinidine, disopyramide, procainamide, phenothiazines, tricyclic antidepressants—exacerbate this dysrhythmia.
1.
Reports have revealed that magnesium sulfate, 1 to
2.
To date, treatment for torsades de pointes consisted of accelerating the heart rate (thereby shortening ventricular repolarization) with isoproterenol (2 to 8 μg/min), while making arrangements for a ventricular pacemaker to overdrive the heart at rates of 90 to 120. Temporary pacing is the most effective and safest method to treat torsades de pointes and prevent its recurrence.
Ventricular Fibrillation
Clinical Features
Ventricular fibrillation is the totally disorganized depolarization and contraction of small areas of ventricular myocardium—there is no effective ventricular pumping activity. The ECG of ventricular fibrillation shows a fine-to-coarse zigzag pattern without discernible P waves or QRS complexes (Fig. 2-15). Ventricular fibrillation is never accompanied by a pulse or a measurable blood pressure.
Ventricular fibrillation is most commonly seen in patients with severe ischemic heart disease, with or without an acute MI. Primary ventricular fibrillation occurs suddenly, without preceding hemodynamic deterioration, whereas secondary ventricular fibrillation occurs after a prolonged period of left ventricular failure or circulatory shock.
Emergency Department Care and Disposition
1.
Current ACLS guidelines recommend immediate electrical defibrillation with 200 J. If ventricular fibrillation persists, defibrillation should be repeated immediately, with 200 to 300 J at the second attempt, increased to 360 J at the third attempt.
2.
If the initial 3 attempts at defibrillation are unsuccessful, cardiopulmonary resuscitation and intubation should be initiated.
3.
Epinephrine in standard dose should be administered, 1 mg intravenously. If this is not successful, high-dose epinephrine may be subsequently given, 0.1 mg/kg, and repeated every 3 to 5 min.
4.
Defibrillation should be attempted after each drug administration, at 360 J, unless lower energy levels have been previously successful.
5.
Successive antidysrhythmics should then be administered with defibrillation attempted after each drug. The recommended sequence is lidocaine, 1.5 mg/kg, bretylium, 5 mg/kg, then possibly magnesium,
6.
Amiodarone, 150 mg over 10 min followed by 1 mg/min for 6 h, may become a preferred treatment for
F/
T after lidocaine has failed.
References
4. http://circ.ahajournals.org/cgi/content/full/112/24_suppl/IV-19
5. http://circ.ahajournals.org/cgi/content/full/112/24_suppl/IV-156
http://circ.ahajournals.org/cgi/content/full/112/22_suppl/III-5
