NURSING ASSESSMENT AND INTERVENTIONS

NURSING ASSESSMENT AND INTERVENTIONS

WHEN LABOR BEGINS

 

Nursing responsibilities when labor begins include history taking, performing a vaginal examination as indicated, and initiating fetal monitoring evaluation. Additionally, the nurse needs to assess the membrane status.

 

History and Baseline Data

• Introduce yourself; maintain eye contact; ask for name of woman’s health care provider, if he or she has beeotified that the woman was coming to the hospital or birth center, and presenting complaints/concerns.

• Establish baseline information

• Assess gravidity, parity, and expected date of delivery or confinement.

• When did contractions begin? How far apart are they? How long do they last? Intensity level?

• Have the membranes ruptured? Time of rupture? Color? Consistency? Amount of fluid? Odor?

• Is there any bloody show?

• How much discomfort is the woman experiencing?

• What, if any, problems has the woman had in this pregnancy? Problems in past pregnancies?

• Blood type and Rh? RhoGAM?

• Group A Streptococcus, hepatitis B, and human immunodeficiency virus (HIV) status

• Last meal/drink? What type of food/drink?

• Medications — nonprescription prescription/illicit/herbal preparations or supplements?

• Support system?

• Establish baseline maternal and fetal vital signs.

• Temperature — elevation ≥ 100.4В°F (≥ 38В°C) suggests a possible infection or dehydration.

• Pulse — evaluate between contractions; may be slightly elevated over the resting rate; should not exceed 105 at rest.

• Respirations — evaluated between contractions; should not exceed 26 breaths/minute.

• Blood pressure — evaluated between contractions.

• A slight elevation over baseline may be attributed to anxiety.

• A blood pressure ≥ 140/90 mm Hg may be suggestive of hypertensive disorder of pregnancy and requires further evaluation. A blood pressure of ≥ 160/100 needs immediate attention and notification of the primary health care provider.

• Assess the fetal heart rate (FHR); if a fetal monitor is to be used, run a 20- to 30-minute strip for baseline data.

• Assess reflexes and clonus.

• Obtain a urine specimen — test the urine for glucose and protein. Protein results may be positive if the membranes have ruptured, but should not exceed 1+ on dipstick.

STANDARDS OF CARE GUIDELINES

Labor and Delivery

• Establish a baseline history for the woman in labor, including maternity history, labor events thus far, medications, herbal preparations, allergies, concerns, and availability of support systems.

• Determine fetal status: fetal heart rate, variability, accelerations, decelerations, fetal movement, cervical status. Notify health care provider of abnormal findings.

• Assess uterine contractions in accordance with established standards of care, facility policy, and maternal and fetal condition.

• Monitor maternal and fetal status in accordance with established standards of care, facility policy, and maternal and fetal condition.

• Make sure that appropriate medical personnel are available within the facility during the administration of oxytocin (Pitocin) and prostaglandins in accordance with ACOG guidelines.

• Perform the following interventions: change mother’s position, administer oxygen, intiate or increase I.V. fluids, administer tocolytics, and notify the health care provider, for the following conditions:

• Nonreassuring or repetitive variable decelerations

• Repetitive late decelerations

• Prolonged decelerations, bradycardia, or tachycardia.

• Notify health care provider for the following:

• Abnormal maternal vital signs

• Nonreassuring fetal tracing.

• Assist the woman with breathing and pain control techniques during contractions.

• Assess woman and partner or significant others for coping, and work with them to carry out the birth plan.

 

Methods for Determining Fetal Presentation

 

Leopold’s maneuvers

 

Determined by abdominal palpation

 

·       First maneuver (see A) — to determine fetal presentation (longitudinal axis) or the part of the fetus (fetal head or breech) that is in the upper uterine fundus.

• Second maneuver (see B) — to determine the fetal position or identify the relationship of the fetal back and the small parts to the front, back, or sides of the maternal pelvis. Still facing the woman, place hands on either side at the middle of the abdomen. While one hand stabilizes the one side of the uterus, the other hand pushes the contents of the abdomen toward the other hand to stabilize the infant for palpation. Next, palpate, applying gentle but deep pressure, beginning at the midline near the fundus and continue down the side (posteriorly) toward the woman’s back. Continue down the abdomen to the symphysis pubis. Determine what fetal body part lies on the side of the abdomen. Reverse the hands and repeat the maneuver. If firm, smooth, and a hard continuous structure, it is likely to be the fetal back; if smaller, knobby, irregular, protruding, and moving, it is likely to be the small body parts (extremities).

• Third maneuver (C,) to determine the portion of the fetus that is presenting. While facing the woman, grasp the part of the fetus situated in the lower uterine segment between the thumb and middle finger of one hand. Using firm, gentle pressure, determine if the head is the presenting part. Pay close attention to the size, contour, and consistency of the presenting part. The head will feel firm and globular. If not engaged into the pelvis, the presenting part is movable. If immobile, engagement has occurred. This maneuver is also known as Pallach’s maneuver or grip.

• Fourth maneuver (see D,) — to determine fetal attitude or the greatest prominence of the fetal head over the pelvic brim. In this maneuver, the examiner faces the woman’s feet. The examiner places his or her hands on the sides of the uterus, below the umbilicus and pointing them toward the symphysis pubis. The examiner then presses deeply with the fingertips facing in the direction of the pelvic inlet (toward the symphysis pubis) and begins to feel for the cephalic prominence. If the cephalic prominence is felt on the same side as the small parts, it is usually the sinciput (fetus’ forehead), and the fetus will be in vertex or flexed position. If the cephalic prominence is felt on the same side as the back, it is the occiput (or crown), and the fetus will be vertex or slightly extended position. If the cephalic prominence is felt equally on both sides, the fetus’ head may be in a military position (common in posterior position). Then move the hands toward the pelvic brim. If the hands converge (come together) around the presenting part, it is floating. If the hands diverge (stay/move apart), the presenting part is either dipping or engaged in the pelvis.

Vaginal Examination

Explain the procedure to the woman. Place her in a lithotomy position.

• Conduct examination gently, under aseptic conditions.

• Evaluate the following:

• Condition of cervix

• Hard or soft (in labor, cervix is soft).

• Effaced and thin or thick and long (in labor, cervix is thin and effaced). Measured in percentages from 0% to 100%.

• Easily dilatable or resistant.

• Closed (fingertip, < 1 cm) or open (dilated); degree of dilation, measured in centimeters from 1 to 10 cm (complete dilation).

• Presentation

• Breech, cephalic (head), or shoulder.

• Caput succedaneum (edema occurring in and under fetal scalp) present (small or large).

• Station identified: engaged, floating.

• Position

• Cephalic presentation (identification of the sagittal suture and of its direction).

• Location of posterior fontanelle.

• Membranes — intact or ruptured

• Amount and color of fluid.

• Passage of meconium; consistency of meconium (eg, thin, thick, particulate matter)

• Odor.

• Bulging.

• Rupture usually increases frequency and intensity of uterine contractions.

• ROM may be contraindicated in presence of vaginal bleeding, premature labor, or abnormal fetal presentation or position.

• Perineum — assess for ulcerations or vesicles that might indicate sexually transmitted disease, such as syphilis or genital herpes. Note: If these are present, stop the examination and notify the primary care provider.

 

Sterile Speculum Examination

In some situations (eg, premature rupture of membranes or rupture of membranes [ROM] without labor), a vaginal examination is deferred and a sterile speculum examination (SSE) is done instead.

• Explain the procedure to the woman.

• Ask her to empty her bladder.

• Have her remove all clothing from the waist down, and give her a sheet to cover herself.

• Place her in a lithotomy position. Place a pillow under her head and place her feet in the stirrups. To ensure the woman is not on her back, place a hip roll under her left hip.

• Drape her legs and the abdomen (optional).

• Position adequate lighting at the perineum. Make sure it is not touching the woman. Position a stool at the end of the examination table.

• Select a sterile speculum. Using aseptic technique, open the package.

• Put on sterile gloves.

• Sitting on the stool, ask the woman to gently spread her legs as far as possible.

• Explain to the woman that anytime she becomes upset or experiences pain during the SSE to let you know. If that occurs, stop the examination, but do not remove your fingers, just hold your hand still. Also explain to the woman that she will occasionally feel vaginal pressure during the SSE.

• With the nondominant hand, place two fingers just inside the introitus and gently press down on the base of the vagina. Then insert the closed speculum past the fingers at a 45-degree downward angle.

• Using no lubricant, grasp the speculum with the dominant hand.

• After the speculum is in the vagina, remove your fingers. Turn the blades of the speculum into a horizontal position, maintaining a moderate downward pressure.

• When the cervix is in view, tighten the thumbscrew to keep the blades open.

• When the examination is completed, release the thumbscrew. Hold the blades apart by pressing on the thumb piece and begin withdrawing the speculum until the cervix is released from between the blades.

• Release the thumb piece, allowing the blades to close. Rotate the speculum sideways, exerting a downward pressure, and remove the blade.

• Wipe any moisture or discharge from the perineal area.

Assessing the Woman’s or Couple’s Expectations and Concerns

• What are their concerns?

• How anxious are they?

• What has been their preparation for labor (type, by whom, and when)?

• What is their understanding of the labor process?

• What are their expectations of the labor and delivery process (prepared childbirth, anesthesia, analgesics, use of birthing room, and so forth)?

• How well are they coping and how well are they communicating with each other?

• Review written birth plan with the couple.

FETAL HEART ASSESSMENT

 

The initial purpose of electronic fetal monitoring (EFM) was to identify nonreassuring or unfavorable FHR characteristics that may indicate a fetus at risk for asphyxia. With this early recognition of a nonreassuring status, interventions could then be applied to prevent fetal death and neonatal morbidity. However, after more than two decades of research and experience using EFM, the purpose is now to identify FHR characteristics that allow us to assess fetal well-being and FHR response to labor to make appropriate physiologic-based clinical decisions. Fetal heart assessment can be accomplished either externally, internally, or a combination of the two. Techniques used to assess the FHR and uterine activity (UA) can be nonelectronic or electronic techniques.

Maternal Conditions or Risk Factors and Fetal/Neonatal Implications

• Cardiac — underlying cardiac disease such as anemia or history of cardiac insufficiency; hypertensive disorders (chronic hypertension, preeclampsia, kidney disease, HELLP syndrome). Possible fetal/neonatal implications:

• Small for gestational age (SGA)/intrauterine growth restriction (IUGR)

• Hydrops

• Hypoxemia

• Decreased amniotic fluid

• Preterm labor (PTL)/birth

• Placental abruption

• Poor tolerance to labor

• Respiratory — smoking, asthma, infections. Possible fetal/neonatal implications:

• SGA/IUGR

• Hypoxemia

• Presence of meconium

• PTL/birth

• Neurologic — stroke, underlying neurologic disease. Possible fetal/neonatal implications:

• Hypoxemia

• Placental abruption

• Renal — infection, development of calculi, fluid/electrolyte imbalance, anemia, complications of dialysis. Possible fetal/neonatal implications:

• SGA/IUGR

• Decreased amniotic fluid

• PTL/birth

• Decreased/reversed umbilical blood flow

• GI — nutritional compromise, constipation/hemorrhoids, gall bladder disease, electrolyte imbalance. Possible fetal/neonatal implications:

• SGA/IUGR

• Altered electrolytes — if prolonged, may adversely affect fetus

• Hematologic — anemia, deep vein thrombosis, antiphospholipid antibody syndrome, thrombocytopenia. Possible fetal/neonatal implications:

• SGA/IUGR

• Hypoxemia, cardiac dysrhythmias

• PTL/birth

• Psychosocial/Mental Health — lack of prenatal care, effects of prescribed/nonprescribed medications, malnutrition, substance abuse (alcohol, illicit drugs), increased stress, domestic violence. Possible fetal/neonatal implications:

• SGA/IUGR

• Congenital anomalies

• Poor tolerance of labor

• Placental abnormalities

• PTL/birth

• Decreased amniotic fluid

• Neonatal infection

• Hypoxemia

Nonelectronic Techniques of Fetal Heart Monitoring

Nonelectronic techniques of fetal heart monitoring (FHM) include auscultation and palpation.

 

Auscultation

Auscultation is a means of assessing the FHR by using a fetoscope or handheld Doppler device, to determine the rate, rhythm and general increases and decreases in the FHR. Intermittent auscultation is the auditory assessment of the FHR at selected intervals over time

TABLE 37-2 Frequency of Auscultation: Recommended Assessment and Documentation

ORGANIZATION LATENT PHASE ACTIVE PHASE SECOND STAGE ACOG Low risk — q 30 minutes q 15 minutes High risk — q 15 minutes q 5 minutes AWHONN Low risk — q 30 minutes q 15 minutes High risk — q 15 minutes q 5 minutes SOGC Regularly after rupture of membranes or clinically significant change q 15 minutes q 5 minutes when pushing is initiated

 

• Methods:

• Fetoscope

• Leffscope (rarely used today)

• Pinard stethoscope (rarely used today)

• Doptone (handheld Doppler device)

• In some practices, the handheld Doppler or external ultrasound monitor is frequently used

• Capabilities — Detects:

• FHR baseline (fetoscope and Doppler).

• FHR rhythm (fetoscope and Doppler).

• Increases or decreases from FHR baseline (fetoscope and Doppler).

• Differentiation of fetal and maternal heart rates — eliminates error due to fetal demise and EFM equipment (fetoscope only).

• Verification of FHR dysrhythmias visualized on EFM tracing (fetoscope only).

• Clarification of halving or doubling on the EFM tracing (fetoscope only).

• Benefits:

• Neonatal outcomes comparable to use of EFM

• Lower cesarean rates associated with auscultation.

• Technique is noninvasive.

• Patient has increased freedom of movement and ambulation.

• Patient can be monitored if submerged in water (eg, water/Jacuzzi births)

• Increased hands-on care provided due to 1:1 nurse-patient ratio requirement.

• Limitations:

• May limit the ability to hear the FHR (obesity, increased fetal movement or amniotic fluid).

• Does not show variability (long-term [LTV] or short-term [STV]) or decelerations.

·      

 

• Does not offer a continuous recording and is not documented permanently on paper.

• Disrupted by uterine contractions.

• Requires education, practice, skill in auditory assessment

• Requires a 1:1 nurse/patient ratio; therefore, may create need to increase or realign staff.

Procedure for Auscultation

• Explain the procedure to the woman and her support persons.

• Assist the woman into a semi-Fowler’s or wedged lateral position.

• Palpate the maternal abdomen and determine the position and presentation of the fetus by palpation using Leopold’s maneuvers. As internal rotation and descent occur, the location of the FHR changes, swinging gradually from the lateral to the medial area and dropping under the pubic bone until immediately before birth

• Assess uterine contractions (frequency, duration, and intensity) and uterine resting tone by palpation.

• If using Doppler device, apply conduction gel to underside of device.

• Position the bell of the fetoscope or Doppler on the area of the abdomen where maximum fetal heart sounds can be heard, usually over the back or chest of fetus. If using a fetoscope, use firm pressure. If using Doppler device, avoid frictiooises caused by fingers on the abdominal surface area.

• Assess maternal heart rate by placing a finger on the mother’s radial pulse.

• Differentiate between fetal heart tone and other abdominal sounds.

• FHR — a rapid crisp or ticking sound.

• Uterine bruit — a soft murmur, caused by the passage of blood through dilated uterine vessels; is synchronous with maternal pulse.

• Funic souffle (uterine souffle) — a hissing sound produced by passage of blood through the umbilical arteries; it is synchronous with the FHR.

• Count the FHR after contractions for at least 30 to 60 seconds (60 seconds per Society of Obstetricians and Gynaecologists of Canada [SOGC], 2002) (see Table 37-2).

• In clarifying accelerations and decelerations, the examiner can recount for multiple, consecutive brief periods of 6 to 10 seconds may be helpful, ie, count the FHR for 10 seconds and multiply by 6; or count for 6 seconds and multiply by 10. Note the location and character when counting.

• While auscultating the FHR, identify the baseline FHR, rhythm of the FHR (whether regular or irregular), and any increases or decreases in the FHR.

• Interpret the findings and document per your facility’s policy.

• Share the information with the woman and her support persons.

 

Interventions for Auscultation

• Reposition the woman and reassess FHR as needed.

• Increase the frequency of auscultation to clarify the FHR changes.

• Auscultate with the next uterine contraction to assess if changes from the baseline FHR are occurring.

• Consider the use of EFM to assess the type of deceleration or the FHR baseline variability.

• Consider other assessment tools (eg, vibroacoustic stimulation or scalp stimulation) to further evaluate and clarify FHR characteristics.

• Continue assessment with auscultation.

• Use fetoscope if irregular rhythm is heard to validate presence/absence of dysrhythmic FHR patterns.

• Notify primary care provider of findings.

Assessing Uterine Contractions by Palpation

• Uterine palpation should be done throughout an entire contraction, from the start of the contraction to the palpation of the resting tone after that contraction.

• Detects:

• Relative uterine resting tone

• Relative frequency, duration, and relative strength of uterine contractions.

• Benefits:

• Noninvasive; hands-on assessment and care of patient achieved.

• Provides information regarding relative frequency, duration, strength, and resting tone.

• Allows freedom of movement and ambulation for woman.

• Use of touch may be reassuring to the woman.

• Limitations:

• Cannot be used to detect actual intrauterine pressures.

• Subjective in assessment; may lead to different interpretations.

• No permanent record for review/collaboration.

• Maternal size, large amount of adipose tissue, or increased amniotic fluid may limit ability to palpate contractions.

Procedure for Uterine Palpation

• Place fingertips gently on the maternal abdomen over the area of the most uterine firmness. Firmly, but gently, try to indent the uterus.

• As contraction begins, tension will be felt under the fingertips. Uterus will become harder, then slowly soften.

• Intensity is the strength of the contraction measured externally by palpation or internally with an intrauterine pressure catheter (IUPC). Although there is no standard measure for determining palpated contraction intensity, the intensity may be described as follows:

• Mild — the uterine muscle is easily indented and feels like the tip of the nose.

• Moderate — the uterine muscle is moderately firm and can be slightly indented. It feels like the chin.

• Strong (hard) — the uterine muscle is firm and cannot be indented. It feels like the forehead.

• The frequency is measured in minutes and may include a range — represents the time from the beginning of one contraction until the beginning of the next.

• Duration of a contraction is timed in seconds or minutes and is the time from the beginning of the contraction to the end of the contraction (eg, from the moment the uterus first begins to tighten until it relaxes again).

• As labor progresses, the character of the contractions changes and they last longer until the second stage of labor.

• When the cervix becomes completely dilated (end of first stage, beginning of second stage), the contractions may initially stop, then become very strong, last for 60 seconds, and occur at 2- to 3-minute intervals.

• Hyperstimulus

• Frequency < 2 minutes apart

• Uterine relaxation < 30 seconds between uterine contractions

• Lasts > 90 to 120 seconds

• Hypertonus

• Elevated resting tone > 20 to 25 mmHg (depends on IUPC)

• Peak pressure > 80 mm Hg

• Montevideo units (MVUs) > 400 to 440

 

Electronic Techniques of FHM

Uterine Assessment by Tocodynamometer (Tocotransducer)

• Benefits:

• Noninvasive.

• Detects relative uterine resting tone and relative frequency and duration of uterine contraction.

• Does not require ruptured amniotic membranes.

• Generates a tracing for future assessment and permanent record keeping.

• Limitations:

• Subjective.

• Unable to detect uterine contraction intensity and resting tone.

• Unable to accurately detect exact frequency and duration of uterine contractions in some cases such as obesity and PTL.

• Toco is location sensitive; placement may result in false information.

• Sensitive to maternal and fetal movement — may be superimposed on contraction waveform.

• Limits the potential for maternal movement and ambulation during labor.

Uterine Assessment by IUPC

IUPCs can be used to detect actual uterine resting tone, actual frequency, duration, and strength of uterine contractions, to withdraw amniotic fluid for testing, and to perform amnioinfusion. IUPCs are either fluid-filled or sensor-tipped catheters.

Although most facilities use the sensor-tipped IUPCs, the fluid-filled IUPCs are still applicable and used today.

Indications for IUPC

• Nonprogression of labor.

• Presence of uterine scar.

• Patient undergoing oxytocin (Pitocin) induction and augmentation when external methods of assessing uterine activity are inadequate.

• Situation where amnioinfusion is desirable (presence of thick meconium or variable decelerations occurring as a result of oligohydramnios [low amniotic fluid]).

• Need for accurate correlation between FHR and contractions, to differentiate between early and late decelerations

General benefits of IUPCs (fluid-filled and sensor-tipped catheters)

• Objective method of assessing accurate frequency, duration, intensity, and resting tone of the uterine contraction.

• Accurate correlation of timing of FHR changes with UA.

• Tracing generated as a permanent part of the medical record.

General limitations of IUPCs (fluid-filled and sensor-tipped catheters)

• ROM and adequate cervical dilatation required for insertion.

• Invasive procedure.

• Increased risk of uterine infection, uterine or placental rupture, and umbilical cord prolapse.

• Limits the potential for maternal ambulation during labor.

• May be contraindicated in presences of vaginal bleeding and infection where ROM is discouraged to prevent maternal-fetal transmissions (eg, HIV, herpes, group B-strep).

• Differences may occur in readings between fluid-filled and sensor-tipped catheters.

Fluid-filled catheter

• Benefits

• Provides means for aspiration of amniotic fluid to assess for chorioamnionitis.

• Provides means for performing amnioinfusion for oligohydramnios (low amniotic fluid) or to thin out thick, particulate meconium-stained amniotic fluid.

• Limitations:

• Catheter tip may become wedged against uterine wall or fetal part and prevent pressure wave production or produce a distorted or truncated waveform pattern.

• Catheter tip, in relation to the position of the external pressure transducer, may affect pressures.

• Catheter may become obstructed with meconium, vernix, blood, or other particulate matter present in the amniotic fluid.

• Pressure readings may be lower than the sensor-tipped IUPCs.

Sensor-tipped catheter

• Benefits

• Easily zeroed to atmospheric pressure easily; most capable of rezeroing during monitoring.

• Allows for amnioinfusion and aspiration of amniotic fluid as needed.

• Design avoids pressure artifacts that may occur as a result of catheter containing air or being kinked.

• Limitations

• Maternal position may change hydrostatic pressure in uterus, altering readings. (Need to assess baseline resting tone in all positions the mother may resume during labor, ie, left tilt, right tilt, side-lying, sitting up, on labor ball, etc.)

• Pressure readings higher than fluid-filled catheters.

 

Fetal Heart Assessment by Ultrasound Transducer

Monitoring the FHR via ultrasound transducer allows detection of the FHR baseline rate, long-term variability, accelerations, and decelerations.

• Benefits:

• Noninvasive.

• No need for ruptured membranes.

• Provides permanent record for review and collaboration.

• Limitations:

• Signal transmission may be influenced by maternal obesity, occiput posterior, anterior placenta, and fetal movement, providing a weak, absent or false signal.

• Restricts maternal freedom of movement.

• Episodic maternal and fetal movement may interfere with continuous recording.

• Artifact may artificially increase variability.

• Half- or double-counting of FHR may occur, especially with fetal tachycardia or bradycardia.

• Placement

• The US transducer device should be applied over the area of the abdomen where the sharpest fetal heart sound is heard.

• Lubricate the face of the transducer with a thin layer of ultrasonic gel to aid in the transmission of sounds. The transducer should be checked every 4 to 6 hours to ensure the presence of ultrasonic gel. If gel has evaporated, apply another thin layer as needed.

• The transducer will need to be readjusted when the fetus changes positions.

Fetal Heart Assessment by Fetal Spiral Electrode

 

The use of the fetal spiral electrode (FSE) to monitor the FHR allows for detection of FHR baseline rate, variability, accelerations, decelerations, and FHR dysrhythmias.

• Indications for FSE include:

• Unable to accurately detect FHR with external monitoring.

• Maternal or fetal movement interfering with tracing.

• Need to accurately assess FHR periodic/nonperiodic (episodic) changes.

• Patient undergoing oxytocin (Pitocin) induction and augmentation when external methods of assessing uterine activity are inadequate.

• Benefits:

• Accurately depicts STV and LTV.

• Maternal position change does not alter ability to assess FHR or quality of tracing.

• Continuous detection of FHR.

• Limitations:

• Invasive procedure; requires ROM, cervical dilation, and accessible/appropriate fetal presenting part.

• Potential small risk of fetal hemorrhage, injury, or infection.

• May record maternal heart rate in presence of fetal demise.

• Fetal arrhythmias may be missed (not detected) if logic or electrocardiogram activation switch is on.

• A moist environment is necessary for FHR detection.

• Electronic interference and artifact may occur.

Relative Contraindications for IUPC and FSE

• Chorioamnionitis

• Active genital herpes and HIV infections

• Certain fetal presentations and conditions that preclude vaginal examinations, such as placenta previa or undiagnosed vaginal bleeding, shoulder or footling breech presentations and floating or > +3 stations.

• FSE should not be applied to fetal face, fontanelles, or genitalia.

• FSE should not be applied if mother is confirmed carrier of hemophilia and status of fetus is unknown.

Interpretation of Fetal Heart Rate

Baseline Rate

• FHR is the approximate mean heart rate assessed when the mother is not having a contraction and when the fetus is not having FHR changes (periodic or nonperiodic [episodic] changes) or being stimulated.

• FHR is assessed for a minimum of 10 minutes.

• Currently accepted baseline FHR is 110 to 160 bpm.

• Variations from the normal baseline rate are tachycardia, bradycardia, and undulating patterns.

Tachycardia

• FHR > 160 bpm for at least 10 minutes.

• Etiology — maternal causes:

• Fever

• Infection

• Dehydration

• Hyperthyroidism

• Endogenous adrenaline or anxiety

• Medicine or drug response

• Beta-sympathomimetics (terbutaline, ritodrine)

• Ketamine, atropine, and phenothiazines

• Hydroxyzine (Vistaril and Atarax)

• Parasympathomimetics (epinephrine)

• Selected positive inotropic agents (dobutamine and positive chronotropic drugs)

• Over-the-counter medications (decongestants, appetite suppressants, and stimulants or caffeine)

• Illicit drugs (cocaine, amphetamines)

• Anemia

• Nicotine if inhaled (if inhaled, nicotine may increase FHR; if absorbed through a nicotine patch, it may decrease FHR)

• Etiology — fetal causes:

• Infection

• Fetal activity or stimulation

• Compensatory response to acute hypoxemia

• Chronic hypoxemia

• Fetal hyperthyroidism

• Fetal tachyarrhythmias (supraventricular tachycardia)

• Prematurity

• Congenital anomalies

• Cardiac abnormalities or heart failure

• Anemia

• Interventions

• Monitor vital signs, specifically maternal temperature and pulse.

• Assess maternal hydration (initiate or increase I.V. fluids as needed).

• Decrease maternal temperature, if elevated, via an antipyretic.

• Decrease maternal anxiety, give explanations for treatment measures, provide comfort measures, and assist with breathing/relaxation techniques.

• Assess FHR variability and other FHR characteristics — assess need to:

• Change maternal position.

• Administer oxygen by snug face mask (8 to 10 L/minute).

• Assess for possible drug use.

• Assess for tachydysrhythmia.

• If auscultating, apply EFM as needed.

Bradycardia

• A baseline FHR < 110 bpm for at least 10 minutes.

• Fetal bradycardia above 90 bpm in the second stage of labor is not considered abnormal unless there is a loss of variability.

• If variability is present with bradycardia, the bradycardia is considered to be benign or reassuring.

• Bradycardia with loss of variability and late decelerations may be predictive of current or impending fetal hypoxia.

• Etiology — maternal causes:

• Supine position

• Adrenergic-receptor blocking drugs (propranolol)

• Connective tissue disease (systemic lupus erythema)

• Prolonged maternal hypoglycemia

• Hypotension

• Anesthetics (epidural, spinal, pudendal or paracervical)

• Conditions that may cause acute maternal cardiopulmonary compromise (anaphylactic syndrome of pregnancy, pulmonary embolus, cerebral vascular events, uterine rupture, trauma)

• Etiology — fetal causes:

• Mature parasympathetic nervous system (PSNS)

• Acute hypoxemia

• Cardiac structural defect

• Excessive PSNS tone caused by chronic head compression in the vertex, occiput posterior, or transverse presentation (FHR usually does not decrease to less than 90bpm)

• Late or profound hypoxemia

• Umbilical cord occlusion

• Hypothermia

• Interventions:

• Validate maternal heart rate versus FHR.

• Assess fetal movement.

• Perform vaginal examination to assess for prolapsed cord.

• Assess maternal vital signs, specifically blood pressure.

• Assess maternal hydration status (initiate or increase IVF as needed).

• Assess FHR variability and other FHR characteristics — consider:

• Maternal position change.

• Discontinue oxytocin (Pitocin) administration.

• Modify maternal pushing techniques or stop pushing.

• Administer oxygen via snug face mask (8 to 10 L/minute).

• If auscultating, apply EFM to assess FHR and variability.

Undulating

• Repeating cycles or changes in the FHR that result in upward increase in the FHR followed by a decrease in the FHR.

• The increases and decreases have a characteristic repetitive shape in the form of a sine wave.

• The baseline rate is usually within the normal range, a frequency of 2 to 5 cycles/minute and amplitude of 5 to 15bpm above and below the baseline FHR.

• Described as sinusoidal or pseudosinusoidal. Sometimes it is difficult to differentiate one from the other; in that case undulatingis used to describe the pattern.

• Sinusoidal pattern:

• Persistent oscillating pattern: 110 to 160 bpm (uniform wavelike pattern).

• Amplitude of undulations usually 5 to 15 bpm above and below the baseline FHR.

• Frequency of undulation usually 2 to 5 cycles/minute.

• Absent STV; no accelerations, even in response to fetal stimulation or fetal movement.

• The etiology of sinusoidal pattern is unknown but is associated with:

• Rh isoimmunization.

• Abruptio placentae.

• Fetal-maternal hemorrhage.

• Severe fetal acidosis.

• Interventions for sinusoidal patterns include:

• Change maternal position to lateral position.

• Administer oxygen via snug face mask (8 to 10 L/minute).

• Provide I.V. hydration.

• Notify the primary health care provider.

• If etiology necessitates, consider:

• Kleihauer-Betke test

• Expeditious delivery

• Intrauterine fetal blood transfusion via cordocentesis (requires tertiary care facility specializing in advanced clinical procedures).

• Pseudosinusoidal pattern:

• Less uniform wavelike pattern.

• “Saw-toothed” appearances: 110 to 160 bpm.

• Periods of normal variability (STV/LTV) and accelerations may be present.

• Pseudosinusoidal pattern also has an unknown cause but is associated with:

• Opioid administration or ingestion.

• Analgesic administration or ingestion.

• Thumb sucking of the fetus in utero.

Variability

• Beat-to-beat changes in FHR that result from the interplay between the sympathetic and parasympathetic nervous systems.

• Variability indicates adequate oxygenation, normal neurologic function in relation to heart rate and also fetal reserve.

• Oxygenation of the central nervous system influences impulse transmission to FHR.

• Absent or decreased variability may be due to preterm gestation (< 28 to 32 weeks), alteration in the nervous system function, inadequate oxygenation, or by both.

• Normal sleep and wake states, medications, alcohol, and illicit drugs that cause fetal neurological damage, morphine, methadone, anomalies, and previous insults that have damaged the fetal brain can affect the baseline variability.

• STV — moment-to-moment changes (R-to-R intervals) in FHR.

• Present — line is rough and squiggly

• Absent — line is smooth

• Interventions for STV include:

• Maternal position change.

• Assess maternal hydration (initiate/increase IVF as needed).

• Discontinue oxytocin (Pitocin) administration.

• Assess uterine contraction status via palpation.

• Administer oxygen via snug face mask (8 to 10 L/minute)

• Assess maternal vital signs.

• Review fetal tracing for last acceleratory patterns.

• Consider the use of fetal pulse oximetry.

• Notify primary health care provider and plan of delivery/resuscitation of neonate.

• LTV — characterized by fluctuations or oscillations in the FHR described as cycles/minutes.

Frequency of fluctuations can be determined by counting

(1)the number of completed cycles/minute,

(2) the number of turning points,

or (3) the number of crossings over an imaginary line within 1 minute.

 

TABLE 37-3 LTV Categories

AMPLITUDE DESCRIPTION AWHONN CATEGORY NICHD CATEGORY < 3 bpm Undetectable Decreased or minimal Absent 3-5 bpm > undetectable or ≤ 5 bpm Decreased or minimal Minimal 6-25 bpm 6-25 bpm Average or withiormal limits Moderate > 25 bpm > 25 bpm Marked or salutatory Marked

 

• Average or moderate variability

• Normal phenomenon

• Indicates fetal oxygenation and physiologic ability to compensate for stress

• Awake and active fetus responding to its environment

• Decreased/minimal variability

• Quiet sleep state

• May be significant for presence of hypoxia/acidosis

• Centrally acting drugs

• Congenital neurologic abnormality

• Dysrhythmic patterns

• Persistent pattern in absence of medication or known anomalies requires intervention

• Requires notification, further assessment, and the need to look at the total clinical picture

• Marked or saltatory variability

• Precise etiology uncertain

• Primarily intrapartum event

• May be compensatory mechanism and possible early sign of fetal hypoxia

• Research shows an association between normal umbilical cord gases and immediate delivery following the pattern

• Interventions for average or moderate and decreased/minimal LTV include:

• Assess fetal tracing for average variability and accelerations.

• Change maternal position.

• Assess hydration (initiate/increase IVF as needed).

• Perform scalp stimulation or vibroacoustic stimulation to assess fetal well-being.

• Discontinue oxytocin (Pitocin) administration.

• Assess medication influence, illicit drug/alcohol/tobacco ingestion.

• Administer oxygen via snug face mask (8 to 10 L/minute).

• Interventions for marked/saltatory LTV should be patient specific:

• Change maternal position.

• Assess maternal hydration (initiate/increase IVF as needed).

• Discontinue oxytocin (Pitocin) administration.

• Administer oxygen via snug face mask (8 to 10 L/minute).

• Instruct mother to alter her breathing/pushing techniques.

• Administer tocolytics if indicated.

• STV may exist independently of LTV, but LTV cannot exist independently of STV.

Periodic FHR Changes/Patterns

Acceleration or deceleration of FHR may occur in direct relation to uterine activity. An acceleration is an abrupt, transient increases in the FHR above the baseline rate. NICHD defines accelerations as a visually abrupt FHR increases with the onset to peak < 30 seconds above the baseline FHR. There are a myriad of decelerations, such as early, variable, late, prolonged, or combined patterns. Like accelerations, decelerations can be either periodic or nonperiodic (episodic) based on their relationship to UA. Decelerations can be described as either (1)abrupt or rapid onset or (2) gradual onset. Decelerations that meet the abrupt (or rapid) onset are usually caused by cord compression and are commonly referred to as variable decelerations. Decelerations that meet the gradual onset are either early or late decelerations and are distinguished from each other by comparing the nadir (lowest point of the deceleration) to the apex (strongest point) of the UC.

Acceleration

• Physiology — several theories.

• Mild compression of the umbilical cord with the UC occluding only the umbilical vein resulting in a decrease in blood flow to the fetus and decreased fetal systemic blood pressure triggering a compensatory rise (acceleration) in the FHR.

• Direct sympathetic stimulation of the fetus.

• Repetitive fetal movement.

• Characteristics — represents functioning of fetal medulla oblongata and fetal well-being.

• For term: acme = 15 bpm and lasts for 15 seconds from onset to return to baseline

• For preterm (< 32 weeks): acme = 10 bpm and lasts for 10 seconds from onset to return to baseline

• Prolonged accelerations last at least 2 minutes but < 10 minutes.

• Interventions — none required, other than reassuring the patient; assessment of an accurate baseline FHR is essential when accelerations are present; reassuring fetal response.

• Double-peaked accelerations have been associated with minor cord compressions; might require position change.

• Early decelerations — gradual decrease in the FHR where the nadir occurs at the peak of the UC. The NICHD describes early decelerations as the gradual decrease with >30 seconds from the onset to nadir.

• Physiology — gradual decelerations in response to head compression that causes a vagal response; can occur during labor from the fetal head pressing on the cervix, pushing, crowning, or forceps/vacuum extraction. It is a benign pattern and not associated with decreased levels of fetal oxygenation or fetal hypoxemia.

• Characteristics — mirror image of the contraction, and all look the same. Uniform shape. Gradual decrease in FHR.

• Onset begins early in the contraction (NICHD — with the onset to peak in > 30 seconds). Nadir (lowest point) usually reached at the same time as the peak of the uterine contraction.

• Returns to baseline by the end of the contraction.

• Treatment not required; benign pattern.

• Maternal position changes do not usually alter the pattern.

• Late decelerations — gradual decrease and return to FHR baseline as response to uteroplacental insufficiency. (The NICHD describes late decelerations as gradual in onset, with onset to nadir > 30 seconds.)

• Physiology.

• Mechanism complex and not well understood.

• Thought to be fetal response to transient alterations in oxygen transport.

• May be related to time it takes intervillous blood to reach the fetal heart/brain in response to UA.

• Chemoreceptors usually stimulated leading to the transient decrease in FHR (commonly referred to as “reflex lates” because the lateness is “reflex mediated” and not “myocardial” mediated), and these lates are accompanied by normal baseline FHR and average variability.

• Metabolic acidosis can directly influence the electrical conduction and performance of the fetal heart, causing direct myocardial compression of the fetal cardiac conduction system. These lates are “myocardial mediated” and are usually accompanied by a change in the fetal baseline FHR (tachycardia or bradycardia), absent or minimal variability, and the absence of accelerations. Usually indicative of a fetus in metabolic acidemia. A pattern of persistent late decelerations of this nature require immediate attention.

• Characteristics — uniform in shape, usually with a reverse mirror image of the contraction phase; typically reflects the intensity of the uterine contractions.

• Onset is late in the contraction, usually after the acme of the contraction with the nadir of the deceleration occurring well after the acme. (NICHD — Onset to peak in > 30 seconds.)

• Returns to baseline after the end of the contraction. Baseline FHR may be increased with repetitive late decelerations.

• Nadir commonly decreases 5 to 30 bpm and rarely decreases 30 to 40 bpm below the baseline FHR. (NICHD — if decelerations do not decrease below the baseline FHR for a minimum of 15 bpm and lasts for minimum of 15 seconds, it is not classified as a late deceleration, or any type of deceleration.)

• Maternal factors that may decrease uteroplacental circulation include:

• Hypotension (may also be associated with reflex late decelerations).

• Hypertension.

• Placental changes that may affect uteroplacental gas exchange (postmaturity, premature placental aging, calcification, abruption sites, placenta previa, or placental malformations).

• Physiologic conditions that may be associated with decreased maternal oxygen saturation or hemoglobin (hyperventilation, hypoventilation, cardiopulmonary disease).

• Uterine hyperstimulation or hypertonus.

• Increased association with other high-risk pregnancy factors (chronic maternal diseases like diabetes or collagen disease, maternal smoking, poor maternal nutrition, or multiple gestation).

• Interventions — aimed at increasing uteroplacental perfusion by correcting cause.

• Change maternal position to a lateral position (right or left)

• Correct any hypotension through increasing the maintenance I.V. fluids.

• Discontinue uterine stimulation (discontinue oxytocin [Pitocin]).

• Administer oxygen by snug face mask at 8 to 10 L/minute.

• Consider tocolytic administration.

• Provide support and decrease anxiety.

• Reflex lates — late decelerations with average LTV or present STV usually caused by acute physiologic insult (ie, supine hypotension, epidural anesthesia) without resulting severe fetal hypoxia.

• Variable decelerations — visually abrupt decelerations in response to cord compression that vary in depth, duration, and timing. The NICHD further describes variable decelerations as onset to nadir usually occurs in < 30 seconds.

• Physiology — decreased umbilical cord perfusion, usually from umbilical cord compression. Umbilical cord compression can be the result from maternal position, prolapsed cord, cord around a fetal part, second-stage labor, decreased amniotic fluid volume (AFV), a short cord, and a true knot in the cord.

• Characteristics — shape may be “U,” “V,” or “W” or may mimic other patterns. “W”-shaped variable decelerations are more common when the cord is long or wrapped around the fetal body or a cord with a true knot in it.

• Onset is variable (NICHD — Onset to peak in < 30 seconds). May include an acceleration phase that precedes or follows the deceleration pattern and is a component of the variable deceleration pattern. Shoulders generally increase in rate <20bpm and lasting <20 seconds. These are referred to as “shoulders,” and are a compensatory response to hypoxemia (oxygen deprivation) with STV being present. Shoulders are described as reassuring and are not associated with poor outcome.

• Reassuring variable decelerations have the following characteristics: duration of less than 60 seconds; rapid return to baseline FHR; are accompanied by normal baseline rate and FHR variability.

• Nonreassuring variable decelerations have the following characteristics: prolonged return to baseline FHR; presence of overshoots; tachycardia; absence or loss of STV or LTV; persistent to < 60 bpm and > 60 seconds.

• Recovery occurs rapidly, commonly followed by a shoulder. Overshoots or rebound overshoots may also be present after the deceleration pattern. Overshoots or rebound overshoots are a blunt acceleration that follows the variable deceleration. It is a gradual, smooth acceleration that lasts no more than 60 to 90 seconds with an increase in the FHR of 10 to 20 bpm, has no variability, no abruptness, and returns to the baseline FHR gradually. If these are repetitive and accompanied with absent STV is considered “nonreassuring.”

• Interventions involve observing that the return occurs quickly and that there is no loss of variability.

• Change maternal position.

• Vaginal examination for prolapsed umbilical cord or imminent delivery.

• Elevate presenting part — if prolapsed cord.

• Amnioinfusion.

• Discontinue oxytocin, if infusing.

• Provide oxygen at 8 to 10 L/minute by snug face mask if variables are persistent, fetal baseline FHR is increasing and variability is decreasing, or if overshoots are present.

• Assess FHR for accelerations, average variability, and shoulders.

• Provide information and decrease anxiety.

• Instruct mother to alter her pushing technique, if variables occur in second stage.

• Notify primary health care provider, plan for delivery and possible resuscitation of neonate.

• If heard with auscultation, intervene as above, and apply EFM to validate auscultation.

• Combined deceleration patterns

• May result when more than one physiologic mechanism causes a combination of “single” decelerations to occur simultaneously or consecutively. Most patterns are not combined.

• Interpretation of these patterns may be enhanced by assessing onset (gradual versus abrupt), timing, FHR variability, and the presence of accelerations. Although there is no agreed-upon terminology for the identification of these patterns, it is important to recognize that these “single” patterns occur simultaneously.

• Occur predominantly in the first stage of labor and commonly associated with increased uterine activity.

• They are usually described as:

• Late variable decelerations.

• Early variable decelerations.

• Variable decelerations with late components.

• Interventions are based on the type of patterns observed. For example, if the pattern is late and variable decelerations combined, interventions from both late

• decelerations and variable decelerations may be used to correct the situation

Nonperiodic (Episodic) FHR Changes/Patterns

Accelerations or decelerations of the FHR not in direct relation to uterine activity.

• Acceleration — abrupt transient increase in the FHR above the baseline rate; occur spontaneously.

• Physiology

• Response to environmental stimuli (eg, acoustic stimulation) and fetal movement

• Other causes that stimulate the sympathetic nervous system (eg, scalp stimulation, OP presentation, or application of the FSE).

• Characteristics — same as periodic accelerations; represents functioning of fetal medulla oblongata and fetal well-being.

• Interventions — none required, other than reassuring the patient; assessment of an accurate baseline FHR is essential when accelerations are present; reassuring fetal response.

• Variable deceleration.

• Physiology — visually abrupt decelerations in response to cord compression that vary in depth, duration, and timing.

• Characteristics

•  

• Tachycardia (> 160 bpm) with LTV < 5 bpm.

• Sinusoidal pattern.

• Variable decelerations with any of the following:

• Relative drop of 70 bpm or more or an absolute drop to 70 bpm or less for > 60 sec.

• Persistent slow return to BL FHR.

• Recurrent prolonged decelerations (two decelerations of < 70 bpm for > 90 seconds in 15 minutes).

• Criteria for use

• Singleton fetus.

• ≥ 36 weeks of gestation.

• Vertex presentation.

• Ruptured membranes.

• Cervix ≥ 2 cm dilated.

• Fetal station of ≤ 2 cm.

• Nonreassuring FHR pattern as defined by the FDA and United States clinical trials.

• Contraindications

• Ominous FHR pattern requiring immediate intervention.

• Need for immediate delivery (unrelated to FHR pattern) such as active uterine bleeding.

• Documented or suspected placenta previa.

• Infectious diseases that preclude internal monitoring, including active genital herpes, HIV, and hepatitis B and hepatitis C seropositivity.

• Warnings

• Do not use with an electrosurgical unit.

• Do not use in presence of flammable anesthetics.

• The sensor can be used during maternal defibrillation, but data may be inaccurate.

• Do not use to monitor patients during water births, whirlpools, showers or in any situation in which patient is immersed in water.

• Do not leave fetal oxygen sensor in place during vacuum extraction, forceps delivery, or cesarean delivery.

• Do not attempt to insert sensor if the cervix is dilated <2cm or if amniotic membranes are not ruptured.

• Preferred application site for fetal oxygen sensor

• The cheek/temple area of the fetal face is the optimal monitoring site. At this location, problems associated with the presenting part (such as hair, vernix, caput and venous stasis) are avoided.

• End result

• Critical threshold value for FSpO₂ is 30%, ie, the normal value is 30% to 70%; values below 30% indicate fetus with decreased levels of oxygen.

• United States of America Randomized Clinical Trials (USA RCT) demonstrated 50% decrease in cesarean section (C/S) rate in fetuses with nonreassuring FHR tracings when FSpO₂ monitoring was used (overall C/S rate unchanged).

• Clinical indication for uses is nonreassuring FHR pattern in pregnancy ≥ 36 weeks’ gestation. Use is not necessary with normal tracing or severely compromised fetus needing immediate delivery.

• Trends can be observed continuously during labor because FSpO₂ is recorded on the FHR paper in UA section.

• Safety issues

• Fetal sensor is latex-free.

• Factory-sterilized by validated ethylene oxide process.

• No reports of uterine wall/placental perforations or abruptions, umbilical cord trauma, eye or ear injury, other physical injury other than transient impression mark at sensor site.

• Light emitted by sensor is below irradiance required to cause retinal injury.

• Role of the nurse

• Identify patient with a nonreassuring tracing, via exclusion and inclusion criteria, who may require fetal oxygen saturation monitoring.

• Assistance with sensor insertion; if nurse trained and competency validated, can insert fetal pulse oximeters, in accordance with state nurse practice act and your facility’s policy.

• Data interpretation.

• Medical record documentation.

• Identifying normal versus abnormal ranges of fetal oxygen saturation values.

• Administration of intrauterine resuscitation techniques, as needed.

• Notification of/communication with primary health care provider, as indicated.

•  

• May occur prior to labor; may be associated with oligohydramnios or umbilical cord entanglement.

• Nonperiodic variable decelerations that decrease ≥15 bpm with duration ≥ 15 seconds need to receive further evaluation.

• Interventions — same as periodic variable deceleration.

• Prolonged deceleration — decelerations that last longer than 2 minutes but < 10 minutes.

• Physiology — dependent on the cause. Prolonged decelerations may be caused by any of the mechanisms previously discussed with the other deceleration types. These mechanisms include cord compression, head compression, and uteroplacental insufficiency. Factors associated with prolonged decelerations include:

• Profound changes in fetal environment, such as placentae abruptio, uterine hypertonus or hyperstimulation, drug reactions, terminal fetal conditions, maternal death, and umbilical cord accidents.

• Hypotension associated with drug responses or maternal positions, such as sympathetic blockade with anesthesia (epidural), paracervical block, vagal stimulation with vaginal examination or Valsalva, cord impingement, cord prolapse, uterine rupture, maternal seizures, asthma, maternal cardiorespiratory collapse, cord compression for prolonged periods, rapid fetal descent, oligohydramnios, or such procedures as vaginal examination or application of internal fetal monitor (FSE).

• Characteristics — Transient fetal tachycardia and loss of FHR variability may be associated with profound episodes.

• Interventions

• Maternal position change.

• Vaginal examination to check for prolapsed cord, entrapment or rapid fetal. Descent that could mean imminent delivery. If prolapsed cord, elevate presenting part.

• Assess maternal vital signs, especially blood pressure for hypotension.

• Discontinue oxytocin, if infusing.

• Evaluate presenting part to rule out breech presentation.

• Assess maternal hydration (initiate/increase I.V. fluids as needed).

• Administer oxygen via snug face mask (8 to 10 L/minute).

• Administer tocolytics as ordered.

• Perform amnioinfusion

• Provide support/explanation, decrease anxiety, and assist mother with breathing and relaxation techniques.

• Notify primary health care provider, plan for delivery and possible resuscitative care for neonate.

• If auscultating, intervene as noted above and apply EFM to validate assessment heard during auscultation.

Fetal Pulse Oximetry

• The use of fetal pulse oximetry was approved in May 2000 by the Food and Drug Administration (FDA) as an additional method of assessing fetal oxygen during labor; it has not been accepted as standard by ACOG or SOGC.

• Fetal pulse oximetry is an adjunct to FHR monitoring. It does not replace the intrauterine resuscitation techniques currently used to improve fetal oxygenation.

• Advantages

• Measures fetal oxygen saturation directly in real time.

• Noninvasive to the fetus; safe and accurate.

• May reduce uncertainty associated with decelerations and other nonreassuring electronic FHR patterns.

• Based on proven technology used in other clinical settings.

• Decision making for use: Criteria for Nonreassuring FHR Patterns

• Baseline FHR between 100 and 110 bpm with no accelerations > 15 bpm for more than 15 seconds.

• Baseline FHR < 100 bpm with accelerations.

• Increased variability > 25 bpm for > 30 minutes.

• Mild or moderate variables for > 30 minutes.

• Late decelerations occurring ≥ 1 every 30 minutes.

• Decreased variability < 5 bpm for > 30 minute that cannot be otherwise explained by the clinical situation.

• Persistent late decelerations for > 15 minutes.