Fetal Assessment during Labor - · PDF fileC HAPTER 13 Fetal Assessment during Labor 369 T he...

368

Fetal Assessment

during Labor

C h a p t e r

DEITRA LEONARD LOWDERMILK

13

• Identify typical signs of nonreassuring fetalheart rate (FHR) patterns.

• Compare FHR monitoring done by intermittentauscultation (IA) with external and internal elec-tronic methods.

• Explain the baseline FHR and evaluate periodicchanges.

• Describe nursing measures that can be used tomaintain FHR patterns within normal limits.

• Differentiate among the nursing interventionsused for managing specific FHR patterns, in-cluding tachycardia and bradycardia; increasedand decreased variability; and late and variabledecelerations.

• Review the documentation of the monitoringprocess necessary during labor.

LEARNING OBJECTIVES

acceleration Increase in fetal heart rate (FHR); usu-ally interpreted as a reassuring sign

amnioinfusion Infusion of normal saline warmed tobody temperature through an intrauterine catheterinto the uterine cavity in an attempt to increase thefluid around the umbilical cord and prevent com-pression during uterine contractions

baseline fetal heart rate Average FHR during a 10-minute period that excludes periodic and episodicchanges and periods of marked variability

bradycardia Baseline FHR below 110 beats perminute (beats/min)

deceleration Slowing of FHR attributed to a para-sympathetic response and described in relation touterine contractions. Types of decelerations include:early deceleration A visually apparent gradual

decrease of FHR before the peak of a contrac-tion and return to baseline as the contractionends; caused by fetal head compression

late deceleration A visually apparent gradual de-crease of FHR with the lowest point of the de-celeration occurring after the peak of the con-traction and returning to baseline after thecontraction ends; caused by uteroplacental in-sufficiency

variable deceleration A visually abrupt de-crease in FHR below the baseline occurring anytime during the uterine contracting phase andcaused by compression of the umbilical cord.

electronic fetal monitoring (EFM) Electronic sur-veillance of FHR by external and internal methods

episodic changes Changes from baseline pat-terns in the FHR that are not associated with uter-ine contractions

hypoxemia Reduction in arterial PO2 resulting inmetabolic acidosis by forcing anaerobic glycolysis,pulmonary vasoconstriction, and direct cellulardamage

hypoxia Insufficient availability of oxygen to meetthe metabolic needs of body tissue

intermittent auscultation Listening to fetal heartsounds at periodic intervals using nonelectronic orultrasound devices placed on the maternal ab-domen

nonreassuring FHR patterns FHR patterns that in-dicate the fetus is not well oxygenated and re-quires intervention

periodic changes Changes from baseline that oc-cur with uterine contractions

tachycardia Baseline FHR above 160 beats/mintocolysis Inhibition of uterine contractions through

administration of medications; used as an adjunctto other interventions in the management of fetalcompromise related to increased uterine activity

uteroplacental insufficiency Decline in placentalfunction (exchange of gases, nutrients, andwastes) leading to fetal hypoxia and acidosis; ev-idenced by late FHR decelerations in response touterine contractions

Valsalva maneuver Any forced expiratory effortagainst a closed airway, such as holding one’sbreath and tightening the abdominal muscles (e.g.,pushing during the second stage of labor)

variability Normal irregularity of fetal cardiacrhythm or fluctuations from the baseline FHR oftwo cycles or more

KEY TERMS AND DEFINITIONS

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C H A P T E R 13 Fetal Assessment during Labor 369

The ability to assess the fetus by ausculta-tion of the fetal heart was initially de-scribed more than 300 years ago. With theadvent of the fetoscope and stethoscope

after the turn of the twentieth century, the listener could hearclearly enough to count the fetal heart rate (FHR). Whenelectronic FHR monitoring made its debut for clinical usein the early 1970s, it was anticipated that its use would effecta decrease in cerebral palsy and be more sensitive than stetho-scopic auscultation in predicting and preventing fetal com-promise (Simpson & Knox, 2000). Although neither of thesepossibilities has been realized, electronic fetal monitoring(EFM) is a useful tool for visualizing FHR patterns on a mon-itor screen or printed tracing.

Pregnant women should be informed about the equip-ment and procedures used and the risks, benefits, and lim-itations of intermittent auscultation (IA) and EFM. Thischapter discusses the basis for fetal monitoring, the types ofmonitoring, and nursing assessment and management ofnonreassuring fetal status.

Understanding fetal and uteroplacental circulation is im-portant in understanding FHR and uterine activity (UA)monitoring (see Chapter 7).

Fetal ResponseBecause labor is a period of physiologic stress for the fetus,frequent monitoring of fetal status is part of the nursing careduring labor. The fetal oxygen supply must be maintained dur-ing labor to prevent fetal compromise and to promote new-born health after birth. The fetal oxygen supply can decreasein a number of ways:

1. Reduction of blood flow through the maternal vesselsas a result of maternal hypertension (chronic hyper-tension or gestational hypertension); hypotension(caused by supine maternal position, hemorrhage, or epidural analgesia or anesthesia); or hypovolemia(caused by hemorrhage)

2. Reduction of the oxygen content in the maternalblood as a result of hemorrhage or severe anemia

3. Alterations in fetal circulation, occurring with com-pression of the umbilical cord (transient, during uter-ine contractions [UCs]; or prolonged, resulting from

BASIS FOR MONITORING

cord prolapse); placental separation or completeabruption; or head compression (head compressioncauses increased intracranial pressure and vagal nervestimulation with an accompanying decrease in theFHR)

4. Reduction in blood flow to the intervillous space inthe placenta secondary to uterine hypertonus (gener-ally caused by excessive exogenous oxytocin) or sec-ondary to deterioration of the placental vasculature as-sociated with maternal disorders such as hypertensionor diabetes mellitus

Fetal well-being during labor can be measured by the re-sponse of the FHR to UCs. In general, reassuring FHR pat-terns are characterized by the following:

• A baseline FHR in the normal range of 110 to 160beats per minute (beats/min) with no periodicchanges and a moderate baseline variability (see laterdiscussion p. 374)

• Accelerations with fetal movement

Uterine ActivityA normal UA pattern in labor is characterized by the fol-lowing:

• Contractions occurring every 2 to 5 minutes and last-ing less than 90 seconds

• Contractions moderate to strong in intensity, as de-tected by palpation, or intensity is less than 80 mmHg, as measured by an intrauterine pressure catheter(IUPC)

• Thirty seconds or more elapsing between the end ofone contraction and the beginning of the next con-traction

• Between contractions, uterine relaxation should be de-tected by palpation or by an average intrauterine pres-sure of 20 mm Hg or less (Tucker, 2004).

Fetal CompromiseThe goals of intrapartum FHR monitoring are to identifyand differentiate the reassuring patterns from the nonreas-suring patterns, which can be indicative of fetal compromise.Nursing care focuses on interventions promoting adequatefetal oxygenation and interventions for nonreassuring pat-terns if they occur.

Nonreassuring FHR patterns are those associated withfetal hypoxemia, which is a deficiency of oxygen in the

ELECTRONIC RESOURCESAdditional information related to the content in Chapter 13 can be found on

the companion website at http://evolve.elsevier.com/Lowdermilk/Maternity/• NCLEX Review Questions• WebLinks

or on the interactive companion CD • NCLEX Review Questions• Critical Thinking Exercise—Fetal Monitoring• Plan of Care—Electronic Fetal Monitoring dur-

ing Labor


370 U N I T F O U R CHILDBIRTH

arterial blood. If uncorrected, hypoxemia can deteriorate tosevere fetal hypoxia, which is an inadequate supply of oxy-gen at the cellular level. Nonreassuring FHR patterns in-clude the following:

• Progressive increase or decrease in baseline rate

• Tachycardia of 160 beats/min or more

• Progressive decrease in baseline variability

• Severe variable decelerations (FHR less than 60beats/min lasting longer than 30 to 60 seconds, withrising baseline, decreasing variability, or slow return tobaseline)

• Late decelerations of any magnitude, especially thosethat are repetitive and uncorrectable

• Absent or undetected FHR variability

• Prolonged deceleration (greater than 60 to 90 seconds)

• Severe bradycardia (less than 70 beats/min)

The ideal method of fetal assessment during labor contin-ues to be debated. Results from research studies indicate thatboth IA of the FHR and electronic FHR monitoring are as-sociated with similar fetal outcomes in low risk intrapartumpatients (Feinstein, Sprague, & Trepanier, 2000; Thacker,Stroup, & Chang, 2001). Although IA is a high-touch, low-technology method of assessing fetal status during labor thatplaces fewer restrictions on maternal activity, more than 80%of laboring women in the United States are monitored elec-tronically for at least part of their labor (Albers, 2001). Thelack of evidence on the efficacy of EFM should be a factorto consider in decision making about which method of fe-tal assessment is offered to low risk laboring women (Wood,2003).

Intermittent AuscultationIntermittent auscultation uses listening to fetal heart soundsat periodic intervals to assess the FHR. IA of the fetal heartcan be performed with a Leff scope, a DeLee-Hillis feto-scope, or a Doppler ultrasound device. If a Leff scope is used,the domed side should be opened to the connective tubingto the earpieces. The domed side is then applied to the ma-ternal abdomen. The fetoscope is applied to the listener’sforehead because bone conduction amplifies the fetal heartsounds for counting. The ultrasound device transmits ultrahigh-frequency sound waves reflecting movement of thefetal heart and converts these sounds into an electronic sig-nal that can be counted (Fig. 13-1).

One procedure for performing auscultation is as follows:1. Perform Leopold maneuvers (see p. 412) by palpating

the maternal abdomen to identify fetal presentationand position.

2. Place the listening device over the area of maximal in-tensity (see Fig. 14-6 on p. 413) and clarity of the fe-tal heart sounds to obtain the clearest and loudestsound, which is easiest to count. Apply ultrasound gelto Doppler ultrasound device if used.

MONITORING TECHNIQUES 3. Palpate the abdomen for the absence of UA to be ableto count the FHR between contractions.

4. Count the maternal radial pulse while listening to theFHR to differentiate it from the fetal rate.

5. Count the FHR for 30 to 60 seconds between con-tractions to identify the baseline rate. This rate can beassessed only during the absence of UA.

6. Auscultate the FHR during a contraction and for 30seconds after the end of the contraction to identify anyincreases or decreases in FHR in response to the con-traction.

By using IA the nurse can assess the baseline FHR,rhythm, and increases and decreases from baseline (Feinstein,2000). The method and frequency of fetal surveillance dur-ing labor will vary depending on maternal-fetal risk factorsand the preference of the facility. In the absence of risk fac-tors, one recommended practice is to auscultate the FHR asfollows (American Academy of Pediatrics [AAP] & AmericanCollege of Obstetricians and Gynecologists [ACOG], 2002;Association of Women’s Health, Obstetric and NeonatalNurses, [AWHONN], 2003):

• First stageActive phase: every 30 minutes

• Second stageEvery 15 minutes

If risk factors are present, the FHR is auscultated as follows:

• First stageActive phase: every 15 minutes

• Second stageEvery 5 minutes

There is no recommended practice for assessing the FHRin the latent phase of first-stage labor; however, AWHONN(2003) suggests that the FHR be assessed as frequently as ma-ternal vital signs. The FHR also is assessed before and afterambulation, rupture of membranes, and administration ofmedications and anesthesia, and more frequently when non-reassuring FHR patterns are heard (AWHONN, 2003;Tucker, 2004).

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B

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Fig. 13-1 A, Ultrasound fetoscope. B, Ultrasound stetho-scope. C, DeLee-Hillis fetoscope. (Courtesy Michael S. Clement,MD, Mesa, AZ.)

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When the FHR is auscultated and docu-mented, it is inappropriate to use the descriptive termsassociated with EFM (e.g., moderate variability, variabledeceleration) because most of the terms are visual de-scriptions of the patterns produced on the monitor trac-ing. Terms that are numerically defined, however, suchas bradycardia and tachycardia, can be used.

Every effort should be made to use the method of fetalassessment the woman desires, if possible. However, aus-cultation of the FHR in accordance with the frequencyguidelines just given may be difficult in today’s busy laborand birth units. When used as the primary method of fetalassessment, auscultation requires a 1:1 nurse-to-patientstaffing ratio. If acuity and census change so that ausculta-tion standards are no longer met, the nurse must inform thephysician or nurse-midwife that continuous EFM will beused until staffing can be arranged to meet the standards.

The woman can become anxious if the examiner cannotreadily count the fetal heartbeats. It often takes time for theinexperienced listener to locate the heartbeat and find thearea of maximal intensity. To allay the mother’s concerns,she can be told that the nurse is “finding the spot where thesounds are loudest.” If it takes considerable time to locatethe fetal heartbeats, the examiner can reassure the motherby offering her an opportunity to listen to them, too. If theexaminer cannot locate the fetal heartbeat, assistance shouldbe requested. In some cases ultrasound can be used to helplocate the fetal heartbeat. Seeing the FHR on the ultrasoundscreen will be reassuring to the mother if there was initial dif-ficulty in locating the best area for auscultation.

When using IA, UA is assessed by palpation. The exam-iner should keep his or her hand placed over the fundus be-fore, during, and after contractions. The contraction inten-sity is usually described as mild, moderate, or strong. Thecontraction duration is measured in seconds, from the be-ginning to the end of the contraction. The frequency of con-tractions is measured in minutes, from the beginning of onecontraction to the beginning of the next contraction. Theexaminer should keep his or her hand on the fundus afterthe contraction is over to evaluate uterine resting tone or re-laxation between contractions. Resting tone between con-tractions is usually described as soft or relaxed (Goodwin,2000).

Accurate and complete documentation of fetal status andUA is especially important when IA and palpation are be-ing used because no paper tracing record of these assessmentsis provided as with continuous EFM. Labor flow records orcomputer charting systems that prompt notations of all as-sessments are useful for ensuring such comprehensive doc-umentation.

Electronic Fetal MonitoringThe purpose of electronic FHR monitoring is the ongoingassessment of fetal oxygenation. FHR tracings are analyzedfor characteristic patterns that signify specific hypoxic andnonhypoxic events (King & Parer, 2000; Parer & King, 2000).

NURSE ALERT

The two modes of electronic fetal monitoring include theexternal mode, which uses external transducers placed on thematernal abdomen to assess FHR and UA, and the internalmode, which uses a spiral electrode applied to the fetal pre-senting part to assess the FHR and an IUPC to assess UAand pressure. The differences between the external and in-ternal modes of EFM are summarized in Table 13-1.

External monitoringSeparate transducers are used to monitor the FHR and

UCs (Fig. 13-2). The ultrasound transducer works by re-flecting high-frequency sound waves off a moving interface:in this case, the fetal heart and valves; therefore short-termvariability and beat-to-beat changes in the FHR cannot beassessed accurately by this method. It is sometimes difficultto reproduce a continuous and precise record of the FHRbecause of artifacts introduced by fetal and maternal move-ment. The FHR is printed on specially formatted monitorpaper. The standard paper speed is 3 cm/min. Once the areaof maximal intensity of the FHR has been located, con-ductive gel is applied to the surface of the ultrasound trans-ducer, and the transducer is then positioned over this area.

The tocotransducer (tocodynamometer) measures UAtransabdominally. The device is placed over the fundus abovethe umbilicus. UCs or fetal movements depress a pressure-sensitive surface on the side next to the abdomen. The to-cotransducer can measure and record the frequency, regularity,and approximate duration of UCs but not their intensity. Thismethod is especially valuable for measuring UA during thefirst stage of labor in women with intact membranes or forantepartum testing. Because the tocotransducer of most elec-tronic fetal monitors is designed for assessing UA in the termpregnancy, it may not be sensitive enough to detect preterm

Critical Thinking ExerciseFetal Monitoring

Keri is 18 years old, gravida 1 at term, and has just beenadmitted to the Labor and Birth Unit. She is assessed tobe at low risk for complications at this time. She is ac-companied by her boyfriend and her mother. Keri seemsanxious about being in labor, and she tells you that shewants to have her baby monitored on the fetal monitormachine because she thinks that will assure her of hav-ing a good outcome to the birth of her baby. How wouldyou respond to Keri’s statement?1 Evidence—Is there sufficient evidence to draw con-

clusions about what response you should give to Keri?2 Assumptions—Describe an underlying assumption

about the following issues related to continuous EFMin comparison to intermittent auscultation:a. Low risk versus high risk pregnanciesb. Infant outcomesc. Staffing (nurse/patient ratio)

3 What implications and priorities for responding to Kerican be drawn at this time?

4 Does the evidence objectively support your conclusion?5 Are there alternative perspectives to your conclusion?

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UA. When monitoring the woman in preterm labor, re-member that the fundus may be located below the level ofthe umbilicus. The nurse may need to rely on the woman toindicate when UA is occurring and to use palpation as an ad-ditional way of assessing contraction frequency.

The external transducer is easily applied by the nurse, butit must be repositioned as the woman or fetus changes

position (see Fig. 13-2, B). The woman is asked to assume asemi-sitting or a lateral position. The equipment is removedperiodically to wash the applicator sites and to give backrubs. Use of an external transducer confines the woman tobed. Portable telemetry monitors allow observation of theFHR and UC patterns by means of centrally located elec-tronic display stations. These portable units permit the


TABLE 13-1

External and Internal Modes of Monitoring

EXTERNAL MODE INTERNAL MODE

FETAL HEART RATE

UTERINE ACTIVITY

Modified from Tucker, S. (2004). Pocket guide to fetal monitoring and assessment (5th ed.). St. Louis: Mosby.

Intrauterine pressure catheter (IUPC):This instrument moni-tors the frequency, duration, and intensity of contractions.The two types of IUPCs are a fluid-filled system and a solidcatheter. Both measure intrauterine pressure at the cath-eter tip and convert the pressure into millimeters of mer-cury on the uterine activity panel of the strip chart. Bothcan be used only when membranes are ruptured and thecervix is sufficiently dilated during the intrapartum period.

Tocotransducer:This instrument monitors frequency andduration of contractions by means of a pressure-sensingdevice applied to the maternal abdomen. Used duringboth the antepartum and the intrapartum periods.

Spiral electrode:This electrode converts the fetal electrocar-diogram (ECG) as obtained from the presenting part to thefetal heart rate (FHR) via a cardiotachometer. This methodcan be used only when membranes are ruptured and thecervix is sufficiently dilated during the intrapartum period.Electrode penetrates into fetal presenting part by 1.5 mmand must be attached securely to ensure a good signal.

Ultrasound transducer: High-frequency sound waves reflect mechanical action of the fetal heart. Noninvasive.Does not require rupture of membranes or cervical dila-tion. Used during both the antepartum and intrapartumperiods.

Tocotransducer(uterine contractions) Ultrasound

transducer(FHR)

A B

Fig. 13-2 A, External noninvasive fetal monitoring with tocotransducer and ultrasound trans-ducer. B, Ultrasound transducer is placed below umbilicus, over the area where fetal heart rate isbest heard, and tocotransducer is placed on uterine fundus. (B, Courtesy Marjorie Pyle, RNC, Life-circle, Costa Mesa, CA.)



woman to walk around during electronic monitoring. Othermonitoring equipment can be used when the woman is sub-merged in water (see Fig. 12-4, C).

Internal monitoringThe technique of continuous internal monitoring allows

an accurate appraisal of fetal well-being during labor (Fig.13-3). For this type of monitoring, the membranes must beruptured, the cervix sufficiently dilated (2-3 cm), and the pre-senting part low enough to allow placement of the electrode.A small spiral electrode attached to the presenting part showsa continuous FHR on the fetal monitor strip.

Internal monitoring of the FHR may be implementedwithout internal monitoring of UA. For UA to be moni-tored, a solid or fluid-filled IUPC is introduced into theuterine cavity. A solid catheter has a pressure-sensitive tipthat measures changes in intrauterine pressure. A catheterfilled with sterile water also can be used. As the catheter iscompressed during a contraction, pressure is placed on thepressure transducer or strain gauge; this pressure is then con-verted into a pressure reading in millimeters of mercury. Theaverage pressure during a contraction ranges from 50 to 85mm Hg. The IUPC can measure the frequency, duration,and intensity of UCs.

The FHR and UA are displayed on the monitor paper,with the FHR in the upper section and UA in the lower sec-tion. Fig. 13-4 contrasts the internal and external modes ofelectronic monitoring. Note that each small square represents10 seconds; each larger box of six squares equals 1 minute(when paper is moving through the monitor at 3 cm/min).

Intrauterine pressure transducer(uterine contractions)

Cardiotachometer (FHR)

Electrode

Catheter

Fig. 13-3 Diagrammatic representation of internal inva-sive fetal monitoring with intrauterine pressure catheter andspiral electrode in place (membranes ruptured and cervix dilated).

10 seconds 1 minute61197 61198

Baseline

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FHR in bpmUA: intensity not measurable

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Fig. 13-4 Display of fetal heart rate and uterine activity on monitor paper. A, External modewith ultrasound and tocotransducer as signal source. B, Internal mode with spiral electrode andintrauterine catheter as signal source. Frequency of contractions is measured from the beginningof one contraction to the beginning of the next. (From Tucker, S. [2004]. Pocket guide to fetal mon-itoring and assessment [5th ed.]. St. Louis: Mosby.)

A B


Tachycardia is a baseline FHR greater than 160 beats/min for a duration of 10 minutes or longer. It can be con-sidered an early sign of fetal hypoxemia, especially when as-sociated with late decelerations and minimal or absent vari-ability. Fetal tachycardia can result from maternal or fetalinfection, such as prolonged rupture of membranes with am-nionitis; from maternal hyperthyroidism or fetal anemia; orin response to drugs such as atropine, hydroxyzine (Vistaril),terbutaline, or illicit drugs such as cocaine or methamphet-amines.

Bradycardia is a baseline FHR less than 110 beats/minfor a duration of 10 minutes or longer. (Bradycardia shouldbe distinguished from prolonged deceleration patterns,which are periodic changes described later in this chapter.)


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Fig. 13-5 Fetal heart rate variability. A, Absent or unde-tected. B, Minimal. C, Moderate. D, Marked. (Modified fromTucker, S. [2004]. Pocket guide to fetal monitoring and as-sessment [5th ed.]. St. Louis: Mosby.)

Baseline Fetal Heart RateThe intrinsic rhythmicity of the fetal heart, the central ner-vous system (CNS), and the fetal autonomic nervous systemcontrol the FHR. An increase in sympathetic response re-sults in acceleration of the FHR, whereas an augmentationin parasympathetic response produces a slowing of the FHR.Usually a balanced increase of sympathetic and parasym-pathetic response occurs during contractions, with no ob-servable change in the baseline FHR.

Baseline fetal heart rate is the average rate during a 10-minute segment that excludes periodic or episodic changes,periods of marked variability, and segments of the baselinethat differ by more than 25 beats/min (National Institute ofChild Health and Human Development [NICHD], 1997).The normal range at term is 110 to 160 beats/min.

Variability of the FHR can be described as irregular fluc-tuations in the baseline FHR of two cycles per minute orgreater (NICHD, 1997). It is a characteristic of baseline FHRand does not include accelerations or decelerations of theFHR. Variability has been described as short term (beat tobeat) or long term (rhythmic waves or cycles from baseline).The current definition for research does not distinguish be-tween short-term and long-term variability because in actualpractice they are viewed together (NICHD, 1997); however,this definition does identify four ranges of variability as seenin Fig. 13-5. These are based on visualization of the ampli-tude of the FHR in the peak-to-trough segment in beats perminute and include the following:

• Absent or undetected variability

• Minimal variability (greater than undetected but notmore than 5 beats/min)

• Moderate variability (6 to 25 beats/min)

• Marked variability (greater than 25 beats/min)In many facilities, short-term and long-term variability

continue to be used to describe the FHR fluctuations. Short-term variability is commonly described as either absent orpresent while long-term variability may be described usingthe above categories (Tucker, 2004).

Absence of or undetected variability is considered non-reassuring. Diminished variability can result from fetal hy-poxemia and acidosis, as well as from certain drugs that de-press the CNS, including analgesics, narcotics (meperidine[Demerol]), barbiturates (secobarbital [Seconal] and pen-tobarbital [Nembutal]), tranquilizers (diazepam [Valium]),ataractics (promethazine [Phenergan]), and general anes-thetics. In addition, a temporary decrease in variability canoccur when the fetus is in a sleep state. These sleep states donot usually last longer than 30 minutes. Table 13-2 contrastskey differences between increased and decreased variability.

A sinusoidal pattern—a regular smooth, undulating wave-like pattern—is not included in the current research defini-tion of FHR variability. This uncommon pattern occurswhen fetal hypoxia results from Rh isoimmunization or fe-tal anemia (Fig. 13-6).

FETAL HEART RATE PATTERNS

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Fig. 13-6 Sinusoidal fetal heart rate. Note the rhythmic un-dulating pattern. (From: Tucker, S. [2004]. Pocket guide to fe-tal monitoring and assessment [5th ed.]. St. Louis: Mosby.)


It can be considered a later sign of fetal hypoxia and isknown to occur before fetal death. Bradycardia can resultfrom placental transfer of drugs such as anesthetics, pro-longed compression of the umbilical cord, maternal hy-pothermia, and maternal hypotension. Maternal supine hy-potension syndrome, caused by the weight and pressure of

the gravid uterus on the inferior vena cava, decreases the re-turn of blood flow to the maternal heart, which then reducesmaternal cardiac output and blood pressure. These responsesin the mother subsequently result in a decrease in the FHRand fetal bradycardia. Table 13-3 contrasts tachycardia withbradycardia.


TABLE 13-2

Increased and Decreased Variability

INCREASED VARIABILITY DECREASED VARIABILITY

CAUSE

CLINICAL SIGNIFICANCE

NURSING INTERVENTION

From Tucker, S. (2004). Pocket guide to fetal monitoring and assessment (5th ed.). St. Louis: Mosby.CNS, Central nervous system; FHR, fetal heart rate.

Dependent on cause; intervention not warranted if associ-ated with fetal sleep states or temporarily associatedwith CNS depressants; consider performing externalstimulation or scalp stimulation during a vaginal exami-nation to elicit an acceleration of FHR or return to mod-erate variability; consider application of spiral elec-trode; assist health care provider with fetal oxygensaturation monitoring if ordered; prepare for birth if soindicated by the primary health care provider

Priority depends on cause: Observe FHR tracing carefullyfor any nonreassuring patterns, including decreasingvariability and late decelerations; if using externalmode of monitoring, consider using internal mode (spiral electrode) for a more accurate tracing. Interven-tion usually not required unless nonreassuring FHR pattern develops

Benign when associated with periodic fetal sleep states,which last 20 to 30 min; if caused by drugs, variabilityusually increases as drugs are excreted

Decreased variability is not reassuring and is considered asign of fetal stress unless it has an identifiable tempo-rary (e.g., fetal sleep) or correctable cause

Decreased variability associated with uncorrectable latedecelerations indicates presence of fetal acidosis andcan result in low Apgar scores

Significance of marked variability not known; increasedvariability from a previous average variability is earliestFHR sign of mild hypoxemia

Hypoxia or acidosisCNS depressantsAnalgesics or narcotics

Meperidine (Demerol)Alphaprodine (Nisentil)MorphinePentazocine (Talwin)

BarbituratesSecobarbital (Seconal)Pentobarbital (Nembutal)Amobarbital (Amytal)

TranquilizersDiazepam (Valium)

AtaracticsPromethazine (Phenergan)Propiomazine (Largon)Hydroxyzine (Vistaril)Promazine (Sparine)

ParasympatholyticsAtropine

General anestheticsPrematurity: �24 wkFetal sleep cyclesCongenital abnormalitiesFetal cardiac dysrhythmias

Early mild hypoxemiaFetal stimulation by the following:

Uterine palpationUterine contractionsFetal activityMaternal activity

Drugs:Illicit drugs (e.g., cocaine and methamphetamines)Sympathomyometic (e.g., terbutaline and asthma

drugs)


Changes in Fetal Heart RateChanges in FHR from the baseline are categorized as peri-odic or episodic. Periodic changes are those that occur withUCs. Episodic changes are those that are not associated withUCs. These patterns include accelerations and decelerations(NICHD, 1997).

AccelerationsAcceleration of the FHR is defined as a visually apparent

abrupt increase in FHR above the baseline rate. The increaseis 15 beats/min or greater and lasts 15 seconds or more, withthe return to baseline less than 2 minutes from the beginningof the acceleration. In preterm gestations the definition of an

acceleration is a peak of 10 beats/min or more above base-line for at least 10 seconds. Acceleration of the FHR for morethan 10 minutes is considered a change in baseline rate.

Accelerations can be periodic or episodic. Periodic ac-celerations are caused by dominance of the sympatheticnervous response and are usually encountered with breechpresentations. Pressure of the contraction applied to the fe-tal buttocks results in accelerations, whereas pressure appliedto the head results in decelerations. Accelerations may oc-cur, however, during the second stage of labor in cephalicpresentations. Episodic accelerations (Fig. 13-7, B) of theFHR occur during fetal movement and are indications of fe-tal well-being.


TABLE 13-3

Tachycardia and Bradycardia

TACHYCARDIA BRADYCARDIA

DEFINITION

FHR �160 beats/min lasting �10 min FHR �110 beats/min lasting �10 min

CAUSE

CLINICAL SIGNIFICANCE

NURSING INTERVENTION

From Tucker, S. (2004). Pocket guide to fetal monitoring and assessment (5th ed.). St. Louis: Mosby.ECG, Electrocardiography; FHR, fetal heart rate.

Priority dependent on cause and based on stage of labor,fetal position and station, and fetal status—intervention not warranted in fetus with heart block

diagnosed by ECG—scalp stimulation may be performed to determine

whether the fetus has the ability to compensate phys-iologically for stress (FHR will accelerate)

—all interventions to improve fetal oxygenation (i.e.,lateral maternal positioning, hydration, correction ofmaternal hypotension, maternal oxygenation and dis-continuing oxytocin) may be implemented

—carry out health care provider’s orders based on alle-viating cause

Priority dependent on cause:—reduce maternal fever with antipyretics as ordered,

hydration, and cooling measures—oxygen at 8-10 L/min by face mask may be of some

value—carry out health care provider’s orders based on alle-

viating cause (e.g., assist with fetal pulse oximetry ifperformed to collect more data about cause)

Bradycardia with moderate variability and absence of pe-riodic changes is not a sign of fetal compromise if FHRremains �80 beats/min; bradycardia caused by hypoxiais a nonreassuring sign when associated with loss ofvariability and late decelerations

Persistent tachycardia in absence of periodic changesdoes not appear serious in terms of neonatal outcome(especially true if tachycardia is associated with mater-nal fever); tachycardia is a nonreassuring sign when as-sociated with late decelerations, severe variable decel-erations, or absence of variability

Late fetal hypoxemia or hypoxia�-Adrenergic blocking drugs (propranolol; anesthetics for

epidural, spinal, caudal, and pudendal blocks)Maternal hypotensionProlonged umbilical cord compressionFetal congenital heart blockMaternal hypothermiaProlonged maternal hypoglycemia

Early fetal hypoxemiaMaternal feverParasympatholytic drugs (atropine, hydroxyzine)�-Sympathomimetic drugs (ritodrine, isoxsuprine)Intraamniotic infectionMaternal hyperthyroidismFetal anemiaFetal heart failureFetal cardiac dysrhythmiasIllicit drugs (cocaine, methamphetamines)



EVIDENCE-BASED PRACTICE

Routine Doppler Ultrasound

FINDINGS

• No differences between the two groups were found in an-tenatal admissions or obstetric interventions. One trialfound increased perinatal mortality rate in the Dopplergroup, but when these data were added to the pooleddata, the overall difference was not significant. One trialfound that the Doppler group was more likely to have re-peat tests. No trials evaluated the ability of second-trimester Doppler ultrasound to predict preeclampsia, in-trauterine growth restriction, or adverse pregnancyoutcome. No data were found on acute neonatal prob-lems, long-term neurologic development, or maternalpsychologic factors. One trial found that there was an in-crease in birth weight below the 10th percentile in womenwho had intensive repeated fetal ultrasound and Dopplerultrasound examinations, when compared with womenwho had only selected Doppler tests.

LIMITATIONS

• Interventions varied among trials: some evaluated um-bilical artery Doppler alone; others evaluated both um-bilical artery and uteroplacental blood flow. One trial com-pared patients who underwent repeated ultrasoundexamination plus Doppler with patients who underwentDoppler ultrasound examination only if indicated. Somestudies did not allow controls to receive the intervention,and some did allow it. Parameters of measurement dif-fered for the Doppler ultrasound examination. One trialhad differing protocols for high risk and low risk women.The homogeneity of the protocols limits generalizability.Many women dropped out of some studies. No trials in-cluded management protocols for abnormal results.

CONCLUSIONS

• There is no supporting evidence that routine use ofDoppler ultrasound in low risk pregnancy is beneficial tomother or baby. The study showing the intrauterinegrowth restriction (birth weight less than 10th percentile)suggests that repeated ultrasound examinations may beharmful to the fetus. Doppler ultrasound remains a valu-able tool when indicated for high risk pregnancies.

IMPLICATIONS FOR PRACTICE

• Nurses can question the practice of routine Doppler ul-trasound in low risk pregnancy. They can educate patientsabout the risks and benefits of these routines. As patientsbecome more knowledgeable, they can discuss with theirprimary health care provider the indications for the test.

IMPLICATIONS FOR FURTHER RESEARCH

• Large trials are needed to determine Doppler ultrasound’sability to predict preeclampsia, intrauterine growth re-striction, and other adverse outcomes in low risk preg-nancies. Outcomes should include maternal psychologiceffects, neonatal morbidity, and long-term neurologic de-velopment of the baby. Of particular interest is resolvingthe issue of the safety of ultrasound.

BACKGROUND

• Prenatal diagnosticians have used a noninvasive tech-nique called Doppler ultrasound since 1977 to visualizethe movement of blood in a vessel by detecting thechange of frequency of reflected sound. With Doppler ul-trasound the movement of blood in the umbilical arteryand the uteroplacental circulation gives information aboutthe quality of perfusion to the fetus. This can screenwomen with high risk pregnancies for conditions leadingto intrauterine growth restriction and gestational hyper-tension perfusion disorders. There is evidence thatDoppler ultrasound is a better indicator of fetal well-being than the biophysical profile or electronic fetal mon-itoring.

• Use of screening tests in pregnancy should be precededby questions about the proven clinical effectiveness oftesting: sensitivity (ability to detect a problem), specificity(ability to rule out the problem for truly normal subjects),risks of the testing procedure, and what treatments arereasonably available for those with abnormal results. Test-ing can produce anxiety, inappropriate intervention, andiatrogenic (caused by the caregiver) morbidity and mor-tality. Questions have been raised in the past about thesafety of repeated fetal ultrasound examination in gen-eral. Although the procedure is of unquestionable valuein high risk pregnancies, these questions regarding theroutine use of Doppler ultrasound in low risk pregnanciesshould be answered, and the answers should be backedup by supportive evidence from randomized, controlledtrials.

OBJECTIVES

• The authors of the review sought to assess the safety andefficacy of Doppler ultrasound in low risk pregnancies.The intervention was the use of Doppler ultrasound onwomen with low risk pregnancies. Maternal outcomes in-cluded fetal monitoring, kick counts, biophysical profile,ultrasound, operative delivery, and psychologic effects.Perinatal outcomes included birth weight, gestational ageat birth, preterm birth, respiratory status, Apgar score, ad-mission to special care nursery, morbidity, neural de-velopment at 2 years, and perinatal death.

METHODSSearch Strategy

• The authors searched the Cochrane database. Search key-words were not noted.

• Five trials, including 14,338 women, were selected fromFrance, the United Kingdom, and Australia, dated 1992 to 1997.

Statistical Analyses

• Statistical analyses included pooling similar data formetaanalysis and analyzing differences between theDoppler group and controls for each outcome studied. Thereviewers accepted results outside the 95% confidence in-terval as significant.

Reference: Bricker, L., & Neilson, J. (2000). Routine Doppler ultrasound in pregnancy (Cochrane Review). In The Cochrane Library, Issue 2, 2004. Chichester, UK: John Wiley & Sons.



DecelerationsA deceleration (caused by dominance of parasympathetic

response) may be benign or nonreassuring. Three types ofdecelerations are encountered during labor: early, late, andvariable. FHR decelerations are described by their visual re-lation to the onset and end of a contraction and by theirshape.

Early decelerations. Early deceleration of the FHRis a visually apparent gradual decrease and return to baselineFHR in response to fetal head compression. It is a normaland benign finding (NICHD, 1997). The deceleration gen-erally starts before the peak of the UC and returns to thebaseline at the same time as the UC returns to its baseline.Early decelerations may also occur during UCs, during vagi-nal examinations, as a result of fundal pressure, and duringplacement of the internal mode of fetal monitoring. Whenpresent, they usually occur during the first stage of laborwhen the cervix is dilated 4 to 7 cm. Early decelerationssometimes are seen during the second stage when the womanis pushing.

Because early decelerations are considered to be benign,interventions are not necessary. It is valuable to identify earlydecelerations so that they can be distinguished from late orvariable decelerations, which can be nonreassuring and forwhich interventions are appropriate. The different charac-teristics of accelerations of the FHR and early decelerationsare contrasted in Table 13-4.

Late decelerations. Late deceleration of the FHRis a visually apparent gradual decrease in and return to base-

line FHR associated with UCs (NICHD, 1997). The decel-eration begins after the contraction has started, and the low-est point of the deceleration occurs after the peak of the con-traction. The deceleration usually does not return to baselineuntil after the contraction is over (Fig. 13-8, B).

Uteroplacental insufficiency causes late decelerations.Persistent and repetitive late decelerations usually indicatethe presence of fetal hypoxemia stemming from insufficientplacental perfusion. They can be associated with fetal hy-poxemia progressing to hypoxia and acidemia progressingto acidosis. They should be considered an ominous signwhen they are uncorrectable, especially if they are associatedwith decreased variability and tachycardia. Late decelerationscaused by the maternal supine hypotension syndrome areusually correctable when the woman turns on her side to dis-place the weight of the gravid uterus off the vena cava. Suchlateral positioning allows better return of maternal bloodflow to the heart, which in turn increases cardiac output andblood pressure.

Late decelerations caused by uteroplacental insufficiencycan result from uterine hyperstimulation with oxytocin, ges-tational hypertension, postdate or postterm pregnancy, am-nionitis, small-for-gestational-age (SGA) fetus, maternal diabetes, placenta previa, abruptio placentae, conductionanesthetics (producing maternal hypotension), maternal car-diac disease, and maternal anemia. The clinical significanceand nursing interventions are described in Table 13-5.

Variable decelerations. Variable deceleration isdefined as a visual abrupt decrease in FHR below the base-line. The decrease is 15 beats/min or more, lasts at least 15seconds, and returns to baseline in less than 2 minutes fromthe time of onset (NICHD, 1997). Variable decelerations oc-cur any time during the uterine contracting phase and arecaused by compression of the umbilical cord. Table 13-5 con-trasts late deceleration with variable deceleration.

The pattern of variable decelerations differs from thoseof early and late decelerations, which closely approximatethe shape of the corresponding UC. Instead, variable de-celerations often have a U or V shape, characterized by arapid descent to and ascent from the nadir (or depth) of thedeceleration (Fig. 13-8, C ). Some variable decelerations arepreceded and followed by brief accelerations of the FHR,known as “shouldering,” which is an appropriate compen-satory response to compression of the umbilical cord.

Variable decelerations may be related to partial, briefcompression of the cord. If encountered in the first stageof labor, they usually can be resolved by changing themother’s position, such as from one side to the other. Oxy-gen administration by face mask to the mother is some-times helpful. Variable decelerations are most commonlyfound during the second stage of labor as a result of um-bilical cord compression during fetal descent (Freeman,Garite, & Nageotte, 2003). If repetitive variable decelera-tions occur during the second stage, it is important to dis-courage the woman from pushing with every contraction

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Fig. 13-7 A, Acceleration of fetal heart rate (FHR) with uter-ine contractions. B, Acceleration of FHR movement. (FromTucker, S. [2004]. Pocket guide to fetal monitoring and as-sessment [5th ed.]. St. Louis: Mosby.)

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Text continued on p. 382.



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61181

Head compression (HC)Early deceleration

Uteroplacental insufficiency(UPI)

Late deceleration

Umbilicalcord compression

(CC)Variable deceleration

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61180

FHRVariable shape

FHRUniform shape

FHRUniform shape

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Recovery at end of contraction

Late recovery

Variable time relationship to contractions

Rapid return

Sudden drop

Onset at beginningof contraction

Fig. 13-8 Deceleration patterns. A, Early decelerations caused by head compression. B, Latedecelerations caused by uteroplacental insufficiency. C,Variable decelerations caused by cord com-pression. (From Tucker, S. [2004]. Pocket guide to fetal monitoring and assessment [5th ed.]. St. Louis: Mosby.)

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B

C



TABLE 13-4

Accelerations and Early Decelerations

ACCELERATION EARLY DECELERATION

Description

Shape

Onset

Recovery Less than 2 min from onset

Amplitude Usually 15 beats/min above baseline

Baseline

Occurrence

Cause

None required None required

From Tucker, S. (2004). Pocket guide to fetal monitoring and assessment (5th ed.). St. Louis: Mosby.

Nursing intervention

Reassuring pattern not associated with fetal hypoxemia, acidemia, or low Apgar scores

Acceleration with fetal movement signifies fetalwell-being, representing fetal alertness orarousal states

Clinical significance

Head compression resulting from the following:—Uterine contractions—Vaginal examination—Fundal pressure—Placement of internal mode of monitoring

Spontaneous fetal movementVaginal examinationReaction to external soundsElectrode application, scalp stimulationBreech presentation, occiput posterior positionUterine contractionsFundal pressureAbdominal palpation

Repetitious (occurs with each contraction); usually occurs between 4- and 7-cm dilation and in second stage of labor

Variable; may be repetitive with each contraction

Usually associated with average baseline variability

Usually associated with average baseline vari-ability

Usually proportional to amplitude of contraction; rarely decelerates below 100 beats/min

By end of contraction as uterine pressure returns to its resting tone

Early in contraction phase before peak of contraction

Onset to peak (30 sec; often precedes or occurssimultaneously with uterine contraction)

Uniform shape; mirror image of uterine contraction

May resemble shape of uterine contraction or bespikelike

Transitory decrease of FHR below baselineconcurrent with uterine contractions (see Fig. 13-8, A)

Transitory increase of fetal heart rate (FHR) abovebaseline (see Fig. 13-7)

TABLE 13-5

Late Decelerations and Variable Decelerations

LATE DECELERATION VARIABLE DECELERATION

Description

Shape

Onset

Recovery Well after end of contraction Return to baseline is rapid and �2 min from onset,sometimes with transitory acceleration or accel-eration immediately before and after decelera-tion (shouldering or “overshoot”); slow return tobaseline with severe variable decelerations

Onset of deceleration to the beginning of nadir,�30 sec; decrease in FHR baseline is �15beats/min, lasting �15 sec; variable times incontracting phase; often preceded by transitoryacceleration

Late in contraction phase; after peak of contrac-tion; nadir of deceleration occurs after peak ofcontraction

Variable; characterized by sudden decrease in FHRin V, U, or W shape

Uniform; mirror image of uterine contraction; maybe deep or shallow

Abrupt decrease in FHR that is variable in dura-tion, intensity, and timing related to onset ofcontractions (see Fig. 13-8, C)

Transitory gradual decrease in fetal heart rate(FHR) below baseline rate in contracting phase(see Fig. 13-8, B)



TABLE 13-5

Late Decelerations and Variable Decelerations—cont’d

LATE DECELERATION VARIABLE DECELERATION

Deceleration

Baseline

Occurrence

Cause

From Tucker, S. (2004). Pocket guide to fetal monitoring and assessment (5th ed.). St. Louis: Mosby.IV, Intravenous.

The usual priority is:—Change maternal position (side to side, knee

chest)—if decelerations are severe, proceed with follow-

ing measures:a. Discontinue oxytocin if infusingb. Administer oxygen at 8-10 L/min with tight

face maskc. Assist with vaginal or speculum examination

to assess for cord prolapsed. Assist with amnioinfusion if orderede. Assist with fetal oxygen saturation monitor-

ing if orderedf. Assist with birth (vaginal assisted or ce-

sarean) if pattern cannot be corrected

The usual priority is:—Change maternal position (lateral)—Correct maternal hypotension by elevating legs—Increase rate of maintenance IV solution.—Palpate uterus to assess for hyperstimulation—Discontinue oxytocin if infusing—Administer oxygen at 8-10 L/min with tight face

mask—Consider internal monitoring for a more accu-

rate fetal and uterine assessment—Fetal scalp or acoustic stimulation—Assist with fetal oxygen saturation monitoring if

ordered—Assist with birth (cesarean or vaginal assisted) if

pattern cannot be corrected

Nursing interventions

Variable decelerations occur in �50% of all laborsand usually are transient and correctable

Reassuring variable decelerations last �45 sec andabruptly return to the FHR baseline; normalbaseline rate continues; variability does not de-crease

Nonreassuring variable decelerations decrease to�70 beats/min for �60 sec and have a pro-longed return to baseline; baseline rate in-creases, variability is absent

Nonreassuring variable decelerations are associ-ated with fetal acidemia, hypoxemia, and lowApgar scores; severe variable decelerations withaverage baseline variability just before birth areusually well tolerated

Nonreassuring pattern associated with fetal hy-poxemia, acidemia, and low Apgar scores; con-sidered ominous if persistent and uncorrected,especially when associated with fetal tachycar-dia and loss of variability

Clinical significance

Umbilical cord compression caused by the following:

—Maternal position with cord between fetus andmaternal pelvis

—Cord around fetal neck, arm, leg, or other bodypart

—Short cord—Knot in cord—Prolapsed cord

Uteroplacental insufficiency caused by the following:

—Uterine hyperactivity or hypertonicity—Maternal supine hypotension—Epidural or spinal anesthesia—Placenta previa—Abruptio placentae—Hypertensive disorders—Postmaturity—Intrauterine growth restriction—Diabetes mellitus—Intraamniotic infection

Variable; commonly observed late in labor with fetal descent and pushing

Occurs with each contraction; may be observed at any time during labor

Mild variables usually associated with averagebaseline variability; moderate and severe vari-ables often associated with decreasing variabil-ity and increasing baseline rate

Often associated with loss of variability and in-creasing baseline rate

Mild: decelerates to any level, �30 sec with abruptreturn to baseline

Moderate: decelerates to �70 beats/min for 30 to60 sec or �70 to 80 bpm for 60 sec

Severe: decelerates to �70 beats/min for �60 sec,with slow return to baseline

Usually proportional to amplitude of contraction;rarely decelerates to �100 beats/min; however,shallow late decelerations have the same signif-icance


Checklist for Fetal Heart Rate and UterineActivity Assessment (Revised)

Patient’s name Date/time

1. What is the baseline fetal heart rate (FHR)?Beats/min

Check one of the following as observed on the monitor strip:

Average baseline FHR (110 to 160 beats/min)Tachycardia (�160 beats/min)Bradycardia (�110 beats/min)

2. What is the baseline variability?Absence of variabilityMinimal variability (barely detectable up to 5 beats/min)Moderate variability (6 to 25 beats/min)Marked variability (�25 beats/min)

3. Are there any periodic or episodic changes in FHR?Accelerations with fetal movementRepetitive accelerations with each contractionEarly decelerations (head compression)Late decelerations (uteroplacental insuffi-ciency)Variable decelerations (cord compression)

Reassuring (�30 to 45 seconds, abruptreturn to baseline, normal baseline,moderate variability)Nonreassuring(�60 seconds, slow re-turn to baseline, increasing baselinerate, absence of variability)

Prolonged deceleration (�2 minutes to 10minutes)

4. What is the uterine activity/contraction pattern?Frequency (beginning to beginning of UC)Duration (beginning to end of UC)

Abdominal palpation methodStrength (mild, moderate, strong)Resting time (from end of one contraction tobeginning of next one)

Internal monitoring (IUPC)Intensity (mm Hg pressure)Resting tone (mm Hg pressure)

COMMENTS:

PANEL NUMBER:WHAT CAN BE OR SHOULD HAVE BEEN DONE?:

Modified from Tucker, S. (2004). Pocket guide to fetal monitoring and as-sessment (5th ed.). St. Louis: Mosby.

BOX 13-1so that the fetus has time to recover. Variable decelerationsare associated with neonatal depression only when cordcompression is severe or prolonged (i.e., tight nuchal cord,short cord, knot in cord, prolapsed cord). Further de-scriptions of the types of variable decelerations, the clini-cal significance, and nursing interventions are given inTable 13-5.

Prolonged decelerations. A prolonged decel-eration is a visually apparent decrease in FHR below thebaseline 15 beats/min or more and lasting more than 2minutes but less than 10 minutes. A deceleration lastingmore than 10 minutes is considered a baseline change(NICHD, 1997). Generally the benign causes are pelvic ex-amination, application of a spiral electrode, rapid fetal de-scent, and sustained maternal Valsalva maneuver. Other, lessbenign, causes are progressive severe variable decelerations,sudden umbilical cord prolapse, hypotension produced byspinal or epidural analgesia or anesthesia, paracervical anes-thesia, tetanic contraction, and maternal hypoxia, whichmay occur during a seizure. When the deceleration lastslonger than 1 to 2 minutes, a loss of variability with reboundtachycardia usually occurs. Occasionally a period of late de-celerations follows. Prolonged decelerations usually are iso-lated events that end spontaneously. However, when a pro-longed deceleration is seen late in the course of severevariable decelerations or during a prolonged series of latedecelerations, the prolonged deceleration may occur just be-fore fetal death.

Nurses should notify the physician ornurse-midwife immediately and initiate appropriatetreatment for nonreassuring patterns when they see aprolonged deceleration.

The care given to women being monitored by EFM or aus-cultation is the same as that given to the woman having alow risk labor. Care of the woman being monitored by in-ternal methods may vary. FHR pattern recognition and in-tervention may require a nurse to have additional educationand clinical experience.

Assessment and Nursing DiagnosesThe assessment of the woman includes the maternal tem-perature, pulse, respiratory rate, blood pressure, position,comfort, voiding pattern, status of membranes, UC pattern,cervical effacement and dilation, and emotional status. Thefetal assessment includes the fetal presentation, fetal posi-tion, FHR, and identification of both reassuring and non-reassuring FHR patterns. A checklist may be used by thenurse to assess the FHR (Box 13-1). All of the assessmentinformation must be documented in the woman’s medicalrecord.

CARE MANAGEMENT

NURSE ALERT

Evaluation of the EFM equipment also must be done toensure that the equipment is working properly and to allowan accurate assessment of the woman and fetus. A checklistfor fetal monitoring equipment can be used to evaluate theequipment functions (Box 13-2).



Nursing diagnoses for the woman who is being monitoredelectronically for fetal status are based on assessment find-ings. Possible diagnoses include the following:

• Decreased maternal cardiac output related to—supine hypotension secondary to maternal position

• Anxiety related to—lack of knowledge concerning fetal monitoringduring labor—restriction of mobility or movement during EFM

• Impaired fetal gas exchange related to—umbilical cord compression—placental insufficiency

• Acute pain related to—use of belts to position transducers—maternal position—vaginal examinations associated with applicationof maternal or fetal internal monitoring equipmentor fetal blood sampling

• Risk for fetal injury related to—unrecognized hypoxemia, hypoxia, or anoxia—infection secondary to internal monitoring orscalp blood sampling

Expected Outcomes of CareThe primary goals of nursing care are to have a healthy fetaland maternal outcome. The interventions implemented toachieve these outcomes are determined by knowledge of fe-tal status and by standards for care. The planning process in-cludes accommodating the wishes of the woman and family,answering questions, and explaining nursing interventions.

Expected outcomes for the pregnant woman and familyand the fetus include the following:

• The pregnant woman and family will verbalize theirunderstanding of the need for monitoring.

• The pregnant woman and family will recognize andavoid situations that compromise maternal and fetalcirculation.

• The fetus will not have any hypoxemic, hypoxic, oranoxic episodes.

• Should fetal compromise occur, it will be identifiedpromptly, and appropriate nursing interventions suchas intrauterine resuscitation will be initiated and thephysician or nurse-midwife notified.

Plan of Care and InterventionsIt is the responsibility of the nurse providing care to womenin labor to assess FHR patterns, implement independentnursing interventions, document observations and actionsaccording to the established standard of care, and report non-reassuring patterns to the primary care provider (e.g., physi-cian, certified nurse-midwife). See Box 13-3 for a sample pro-tocol for FHR monitoring by IA and EFM during labor.

Although the use of EFM can be reassuring to many par-ents, it can be a source of anxiety to some. Therefore thenurse must be particularly sensitive to and respond appro-priately to the emotional, informational, and comfort needsof the woman in labor and those of her family (Fig. 13-9 andBox 13-4).

Electronic fetal monitoring pattern recognitionNurses must evaluate many factors to determine whether

an FHR pattern is reassuring or nonreassuring. A completedescription of FHR tracings includes both qualitative andquantitative descriptions of baseline rate and variability, pres-ence of accelerations, periodic or episodic decelerations, andchanges in the FHR pattern over time (NICHD, 1997).Nurses evaluate these factors based on other obstetric


Checklist for Fetal Monitoring Equipment

PREPARATION OF MONITOR

1 Is the paper inserted correctly?2 Are transducer cables plugged into the appropriate

outlet of the monitor?3 Is paper speed set to 3 cm/min?

ULTRASOUND TRANSDUCER

1 Has ultrasound transmission gel been applied to thetransducer?

2 Was the fetal heart rate (FHR) tested and noted on themonitor paper?

3 Does a signal light flash or an audible beep occur witheach heart beat?

4 Is the belt secure and snug but comfortable for the la-boring woman?

TOCOTRANSDUCER

1 Is the tocotransducer firmly positioned at the site ofthe least maternal tissue?

2 Has it been applied without gel or paste?3 Was the uterine activity (UA) reference knob pressed

between contractions to adjust the UA baseline to printat the 20 mm Hg line?

4 Is the belt secure and snug but comfortable for the la-boring woman?

SPIRAL ELECTRODE

1 Is the connector attached firmly to the leg plate?2 Is the spiral electrode attached to the presenting part

of the fetus?3 Is the inner surface of the leg plate covered with elec-

trode gel (if necessary)?4 Is the leg plate properly secured to the woman’s thigh?

INTERNAL CATHETER/STRAIN GAUGE

1 Is the length line on the catheter visible at the introitus?2 Is it noted on the monitor paper that a UA test or cal-

ibration was done?3 Has the monitor been set to zero according to manu-

facturer’s directions?4 Is the IUPC properly secured to the woman’s thigh?

Modified from Tucker, S. (2004). Pocket guide to fetal monitoring and as-sessment (5th ed.). St. Louis: Mosby.

BOX 13-2


complications, progress in labor, and analgesia or anesthesia.They also must consider the estimated time interval untilbirth. Interventions are therefore based on clinical judgmentof a complex, integrated process (Haggerty & Nuttall, 2000).

Fetal Monitoring Standards

Nurses who care for women during childbirth are legallyresponsible for correctly interpreting FHR patterns, ini-tiating appropriate nursing interventions based onthose patterns, and documenting the outcomes of thoseinterventions. Perinatal nurses are responsible for thetimely notification of the physician or nurse-midwife in the event of nonreassuring FHR patterns. Perinatal

LEGAL TIP

nurses also are responsible for initiating the institutionalchain of command should differences in opinion ariseamong health care providers concerning the interpre-tation of the FHR pattern and the intervention required.

Nursing management of nonreassuring pat-terns. The term intrauterine resuscitation is sometimes usedto refer to those interventions initiated when a nonreassur-ing FHR pattern is noted; they are directed primarily towardimproving uterine and intervillous space blood flow and sec-ondarily toward increasing maternal oxygenation and cardiacoutput (Parilla, 2002). The following preventive interventionsare described in this chapter: avoiding the supine positionand encouraging maternal position changes; encouraging


Protocol for Fetal Heart Rate Monitoring

MATERNAL AND FETAL ASSESSMENTS

• Obtain a 20-min strip of electronic fetal monitoring (EFM)for all patients admitted to labor unit.

Low Risk Patient

• Auscultate or assess tracing every 30 min in active phaseof first stage of labor.

• Auscultate or assess tracing every 15 min in second stage.

High Risk Patient

• Auscultate or assess tracing every 15 min in active phaseand every 5 min in second stage.

Auscultation: All Patients

• Count baseline fetal heart rate (FHR) between contractions.• Assess FHR during the contraction and for 30 sec after the

contraction.• Note increases or decreases of FHR.• Assess FHR before ambulation.• Interpret FHR data, nursing interventions, and patient re-

sponses.• Notify primary health care provider.

EFM: All Patients

• Assess and interpret baseline FHR, variability of FHR, and presence or absence of decelerations and accelera-tions.

Assessments for All Patients

• Assess uterine activity for frequency and duration, the in-tensity of contractions, and uterine resting tone.

• Assess FHR immediately after rupture of membranes,vaginal examinations, and any invasive procedure.

MATERNAL CARE

• Assist woman to a comfortable position other thansupine.

• Change maternal position at least every 2 hr.

EXTERNAL MONITORINGUltrasound Transducer

Function

• Monitors FHR with high-frequency sound waves.

Nursing Care

• Tap transducer before use to ensure sound transmission.• Apply ultrasound transmission gel to transducer, clean

abdomen and transducer, and reapply gel every 2h andas needed.

• Massage reddened skin areas gently and reposition beltor adhesive device every 2h and as needed.

• Auscultate FHR with stethoscope or fetoscope if in doubtas to validity of tracing.

• Position and reposition transducer prn to ensure receiptof clear, interpretable FHR data.

TocotransducerFunction

• Monitors uterine activity via a pressure-sensing deviceplaced on the maternal abdomen.

Nursing Care

• Position and reposition every 2h and as needed on thefundus, where there is the least maternal tissue.

• Keep abdominal strap snug but comfortable for the la-boring woman.

• Adjust knob between contractions to print between 10 and 20 mm Hg on the monitor strip paper.

• Palpate fundus every 30 to 60 min to assess strength ofcontraction; only frequency and duration of contractionscan be assessed with tocotransducer.

• Do not determine woman’s need for analgesia based onuterine activity displayed on monitor strip.

• Gently massage reddened areas under transducer andbelt hourly and as needed.

INTERNAL MONITORINGSpiral Electrode

Function

• Obtains fetal electrocardiogram (ECG) from presentingpart and converts it into FHR.

Nursing Care

• Ensure that the connector to the scalp electrode is ap-propriately attached to leg plate.

• Reapply electrode paste to leg plate if needed.• Observe FHR tracing on monitor strip for variability.

BOX 13-3


spontaneous short bursts of pushing in response to invol-untary bearing-down urges; and encouraging pushing withmouth open and glottis open with vocalizing. Previously itwas thought that the left lateral maternal position prefer-entially promoted maternal cardiac output, thereby en-hancing blood flow to the fetus. However, it is now knownthat either the right or left lateral maternal position effec-tively enhances uteroplacental blood flow. The key issue isto avoid positioning the laboring woman on her back to re-duce the risk of supine hypotension, which leads to de-creased placental perfusion.

Compression of the umbilical cord vessels results in vari-able decelerations. Amnioinfusion is an intervention that canhelp relieve such pressure on a nonprolapsed umbilical cord.If maternal hypotension caused by acute hemorrhage (hy-povolemia) occurs, the rapid infusion of blood volume ex-panders may be ordered. Until the infusion is established,the nurse can elevate the woman’s legs. Blood pooled in thelegs, especially as a result of sympathetic blockade (e.g.,epidural anesthesia), will then drain quickly into the centralvenous circulation, and this will augment the effective in-travascular volume (Parilla, 2002).


Protocol for Fetal Heart Rate Monitoring—cont’d

• Turn electrode counterclockwise to remove; never pullstraight out from presenting part.

• Administer perineal care after the woman voids duringlabor and prn.

Intrauterine CatheterFunction

• Catheter (solid or fluid filled) that monitors intraamnioticpressure internally.

Nursing Care

• Ensure that the length line on catheter is visible at in-troitus.

• For closed-system catheters, set baseline rate betweenuterine contractions when uterus is relaxed.

• Flush open-system catheter with sterile water before in-sertion and prn.

• For open-system catheters, turn stopcock off to woman,then with pressure valve of strain gauge released, flushstrain gauge, remove syringe, and set stylus to 0 lines ofchart paper; test further according to manufacturer’s in-structions every 3-4h and as needed.

• Check proper functioning by tapping catheter, askingwoman to cough, or applying fundal pressure; observeappropriate inflection on strip chart.

• Keep catheter or cable secured to woman’s leg to preventdislodgment.

REPORTABLE CONDITIONS

• Presence of nonreassuring patterns:• Severe variable decelerations• Late decelerations• Absence of variability• Prolonged deceleration• Severe bradycardia

• Worsening of any pattern• Presence of identifiable fetal dysrhythmias• Difficulty in obtaining adequate FHR tracing or inadequate

audible FHR

EMERGENCY MEASURES

• Implement the following measures immediately in theevent of nonreassuring patterns. The priority will depend

on the type of nonreassurring FHR pattern is present ( re-fer to Tables 13-2, 13-3, and 13-5):

• Reposition patient in lateral position to increase utero-placental perfusion or relieve cord compression.

• Administer oxygen at 8-10 L/min or per hospital protocolby face mask.

• Discontinue oxytocin if infusing.• Correct maternal hypovolemia by increasing intra-

venous (IV) rate per protocol or as ordered.• Assess for bleeding or other cause of pattern change,

such as maternal hypotension.• Notify primary health care provider.• Assist with other methods of assessment such as fetal

oxygen saturation monitoring or interventions such asamnioinfusion.

• Anticipate emergency preparation for surgical interven-tion if nonreassuring pattern continues despite inter-ventions.

DOCUMENTATION*Patient Record: Auscultation

• FHR baseline, rate and rhythm, increases or decreases

Patient Record: EFM

• Method of monitoring, change in method, and adjust-ments to equipment

• FHR range, variability, presence of decelerations or ac-celerations

• Uterine activity as determined by palpation or by exter-nal or internal monitoring

• Interpretation of FHR data, nursing interventions, and pa-tient responses

• Notification of primary health care provider

Monitor Strip

• Patient identification data• Assessments, procedures, and interventions (medica-

tions, etc.)• Notification of primary health care provider• Significant occurrences (sterile vaginal examination, rup-

ture of membranes, etc.)• Adjustments of the monitor equipment

BOX 13-3

*If computer charting system is used, follow institutional policies and system guidelines and protocols.


Oxytocin always should be infused via a piggyback con-nection near the indwelling needle. If FHR patterns changefor any reason, oxytocin stimulation of the uterine musclemust be discontinued. This consists of turning off the in-travenous (IV) line from the piggyback (containing oxytocin)and opening the primary infusion line.

Nurses must assign priorities to interventions to maximizethe efficacy of the intrauterine resuscitation. The first prior-ity is to open the maternal and fetal vascular systems, the sec-ond priority is to increase blood volume, and the third prior-ity is to optimize oxygenation of the circulating bloodvolume. For example, to relieve an acute FHR deceleration,the nurse can do the following:

• Assist the woman to the side-lying position if she is notalready in a lateral position.

• Increase the maternal blood volume by increasing therate of the primary IV infusion or by raising thewoman’s legs.

• Provide oxygen by face mask.Some interventions are specific to the FHR pattern. Nurs-

ing interventions appropriate for the management of tachy-cardia and bradycardia are given in Table 13-2, and those ap-propriate for the management of increased or decreasedvariability are given in Table 13-3. No specific nursing in-terventions are required for the management of FHR ac-celeration or early deceleration (see Table 13-4). However,late and some types of variable FHR decelerations requireaggressive intervention (see Table 13-5). The primary healthcare provider decides whether medical intervention shouldbe instituted, what intervention is indicated, or whether im-mediate vaginal or cesarean birth should be performed.

Other methods of assessment and interventionOther methods of assessment and intervention are de-

signed to be used in conjunction with EFM in an effort toidentify and intervene in the presence of a nonreassuring

FHR. These methods include FHR response to stimulation,fetal oxygen saturation monitoring, fetal blood sampling,amnioinfusion, and tocolysis. Umbilical cord acid-base de-termination is an assessment technique that is a useful ad-junct to the Apgar score in assessing the immediate condi-tion of the newborn.

Fetal heart rate response to stimulation.Stimulation of the fetus is done to elicit an acceleration ofthe FHR of 15 beats/min for at least 15 seconds (Tucker,2004). The two methods of fetal stimulation currently inpractice are scalp stimulation (using digital pressure duringa vaginal examination) and vibroacoustic stimulation (usingan artificial larynx or fetal acoustic stimulation device overthe fetal head for 1 to 2 seconds). An FHR acceleration


Fig. 13-9 Nurse explains electronic fetal monitoring asultrasound transducer monitors the fetal heart rate. (CourtesyMarjorie Pyle, RNC, Lifecircle, Costa Mesa, CA.)

Patient and Family Teaching WhenElectronic Fetal Monitor Is Used

The following guidelines relate to patient teaching and thefunctioning of the monitor.• Explain the purpose of monitoring.• Explain each procedure.• Provide rationale for maternal position other than

supine.• Explain that fetal status can be continuously assessed

by electronic fetal monitoring (EFM), even during con-tractions.

• Explain that the lower tracing on the monitor strip pa-per shows uterine activity; the upper tracing shows thefetal heart rate (FHR).

• Reassure woman and partner that prepared childbirthtechniques can be implemented without difficulty.

• Explain that, during external monitoring, effleurage canbe performed on sides of abdomen or upper portion ofthighs.

• Explain that breathing patterns based on the time andintensity of contractions can be enhanced by the ob-servation of uterine activity on the monitor strip paper,which shows the onset of contractions.

• Note peak of contraction; knowing that contraction willnot get stronger and is half over is usually helpful.

• Note diminishing intensity.• Coordinate with appropriate breathing and relaxation

techniques.• Reassure woman and partner that the use of internal

monitoring does not restrict movement, although sheis confined to bed.*

• Explain that use of external monitoring usually re-quires the woman’s cooperation during positioningand movement.

• Reassure woman and partner that use of monitoringdoes not imply fetal jeopardy.

• Reassure her that the equipment is removed periodi-cally to permit the applicator sites to be washed andother care to be given.

*Portable telemetry monitors allow the FHR and uterine contraction pat-terns to be observed on centrally located display stations. These portableunits permit ambulation during electronic monitoring.

BOX 13-4


usually indicates fetal well-being. If the fetus does not havean acceleration, however, it does not necessarily indicate fe-tal compromise, but further evaluation of fetal well-being isneeded.

Fetal oxygen saturation monitoring. Con-tinuous monitoring of fetal oxygen saturation (FSpO2) or fe-tal pulse oximetry (FPO) is a method of fetal assessment thatwas approved for clinical use by the Food and DrugAdministration in May 2000 (Porter, 2000). FPO works ina way similar to the pulse oximetry used in children andadults. A specially designed sensor is inserted next to the fe-tal cheek or temple area to assess oxygen saturation. The sen-sor is then connected to a monitor, and the data are dis-played on the UA panel of the fetal monitor tracing. Thenormal range of oxygen saturation in the adult is 95% to100%. The normal range for the healthy fetus is 30% to 70%(Simpson & Porter, 2001), with the cutoff value for the crit-ical threshold of FSpO2 at 30% (Garite et al., 2000).

FPO may be used if certain criteria are met, including asingle fetus with at least 36 weeks of gestation in a vertex pres-entation with a nonreassuring FHR pattern. The membranesshould be ruptured, the cervix dilated at least 2 cm, and thefetal station at least a �2 or less (Garite et al., 2000). Thevalue of FSpO2 monitoring is that in the event of nonreas-suring FHR patterns, it could support the decision aboutwhether labor should continue or whether to intervene withan expeditious assisted vaginal or cesarean birth of the fe-tus (Simpson, 2003).

When the use of FPO becomes more widely practiced,the labor nurse’s role will expand to include this type ofmonitoring in practice (Porter, 2000). Simpson and Porter(2001) suggested that nurses will be involved in identifyingpotential candidates for monitoring, inserting the sensor (ac-cording to state nurse practice acts and institutional policies),interpreting data, documenting findings, and communicat-ing with the primary health care provider.

Fetal scalp blood sampling. Sampling of the fe-tal scalp blood was designed to assess the fetal pH, PO2, andPCO2. The procedure is performed by obtaining a sample offetal scalp blood through the dilated cervix after the mem-branes have ruptured. The scalp is swabbed with a disinfectingsolution before making the puncture, and the sample is thencollected. However, the blood gas values vary so rapidly withtransient circulatory changes that fetal blood sampling is sel-dom performed in the United States (Gilstrap, 2004). Whenused, it is usually in tertiary centers with the capability forrepetitive sampling and rapid report of results. The circula-tory changes that cause the variability and thus underminethe utility of this procedure are maternal acidosis or alkalo-sis, caput succedaneum, the stage of labor, and the time re-lation of scalp sampling to UCs.

Amnioinfusion. Amnioinfusion is used during la-bor either to supplement the amount of amniotic fluid toreduce the severity of variable decelerations caused by cordcompression or to dilute meconium-stained amniotic fluidwith saline or lactated Ringer’s solution (Hofmeyr, 2002;

Parer & Nageotte, 2004). The procedure to supplement am-niotic fluid is indicated for patients with oligohydramnios,secondary to uteroplacental insufficiency, premature ruptureof membranes, or postmaturity, who are at risk for variabledecelerations because of umbilical cord compression.

Oligohydramnios is an abnormally small amount of am-niotic fluid or the absence of amniotic fluid. Without thebuffer of amniotic fluid, the umbilical cord can easily be-come compressed during contractions or fetal movement,diminishing the flow of blood between the fetus and pla-centa, as evidenced by variable decelerations. Amnioinfusionreplaces the “cushion” for the cord and relieves both the fre-quency and intensity of variable decelerations.

Amnioinfusion also is indicated in the presence of mod-erate to thick meconium to dilute and flush out the meco-nium with the intent of avoiding meconium-aspiration syn-drome in the neonate (Hofmeyr, 2002).

Risks of amnioinfusion are overdistention of the uterinecavity and increased uterine tone. Techniques of amnioin-fusion treatment vary, but usually fluid is administeredthrough an IUPC. The woman’s membranes must be rup-tured for the IUPC placement. The fluid is administered byattaching plastic (IV) tubing to a liter of normal saline or lac-tated Ringer’s solution through a port in the IUPC. Dou-ble-lumen IUPCs are preferred because the IUP can be mon-itored without stopping the procedure. The fluid is usuallywarmed with a blood warmer before administration for thepreterm or SGA fetus (Torgersen, 2004). The flow rate canbe by bolus or continuous flow or by a combination of thesetwo methods.

Intensity and frequency of UCs should be continually as-sessed during the procedure. The recorded uterine restingtone during amnioinfusion will appear higher than normalbecause of resistance to outflow and turbulence at the endof the catheter. The true resting tone can be checked by dis-continuing the amnioinfusion when using a single-lumenIUPC (Tucker, 2004).

Tocolytic therapy. Tocolysis (relaxation of theuterus) can be achieved through the administration of drugsthat inhibit UCs. This therapy can be used as an adjunct toother interventions in the management of fetal stress whenthe fetus is exhibiting nonreassuring patterns associated withincreased UA. Tocolysis improves blood flow through theplacenta by inhibiting UCs. Tocolysis may be considered bythe primary health care provider and implemented whenother interventions to reduce UA, such as maternal positionchange and discontinuance of an oxytocin infusion, have noeffect on diminishing the UCs. A tocolytic drug such asmagnesium sulfate or terbutaline can be administered in-travenously to decrease UA (Tucker, 2004). If the FHR pat-tern improves, the woman may be allowed to continue la-bor; if there is no improvement, immediate cesarean birthmay be needed.

Umbilical cord acid-base determination.In assessing the immediate condition of the newborn afterbirth, a sample of cord blood is a useful adjunct to the Apgar



score. The procedure is generally done by withdrawing bloodfrom the umbilical artery and having the blood tested forpH, PCO2, and PO2. Umbilical cord gas measurements reflectthe acid-base status of the newborn at birth, a measurementnot reflected in the Apgar score (Gilstrap, 2004). If acidosisis present (e.g., pH 7.10 to 7.18) the type of acidosis is de-termined (respiratory, metabolic, or mixed) by analyzing theblood gas values (Table 13-6).

Patient and family teachingPart of the nurse’s role includes acting as a partner with

the woman to achieve a high-quality birthing experience. Inaddition to teaching and supporting the woman and her fam-ily with understanding of the laboring and birth process,breathing techniques, use of equipment, and pain manage-ment techniques, the nurse can assist with two factors thathave an effect on fetal status: pushing and positioning. Thenurse should provide information and support to the womanwith regard to these two factors.

Maternal positioning. Maternal supine hypoten-sive syndrome is caused by the weight and pressure of thegravid uterus on the inferior vena cava when the woman isin a supine position. This decreases venous return to thewoman’s heart and cardiac output and subsequently reducesher blood pressure. The low maternal blood pressure de-creases intervillous space blood flow during UCs and resultsin fetal hypoxemia. This is reflected on the fetal monitor asa nonreassuring FHR pattern, usually late decelerations. Thenurse should solicit the woman’s cooperation in avoiding thesupine position. The woman should be encouraged to main-tain a side-lying position or semi-Fowler’s position with a lat-eral tilt to the uterus.

Discouraging the Valsalva maneuver. TheValsalva maneuver can be described as the process of mak-ing a forceful bearing-down attempt while holding one’s

breath with a closed glottis and tightening the abdominalmuscles. This process stimulates the parasympathetic divi-sion of the autonomic nervous system, producing a vagal re-sponse, and results in the decrease of the maternal heart rateand blood pressure. Prolonged pushing in this manner candecrease placental blood flow, alter maternal and fetal oxy-genation, decrease the fetal pH and PO2, increase the fetalPCO2, and increase the likelihood of fetal hypoxemia, as re-flected in FHR pattern changes.

During the second stage of labor, when the woman needsto push, an alternative to breath holding with a closed glot-tis is to perform the open-mouth and open-glottis breath-ing-pushing technique. The nurse should instruct the womanto keep her mouth and glottis open and to let air escape fromthe lungs during the pushing process. This may result in anaudible grunting sound and will prevent the Valsalva ma-neuver. Some providers of care prefer the laboring-downprocess or delayed pushing, which is to refrain from push-ing in the early second stage of labor. The natural forces oflabor contractions are used to move the fetus down the birthcanal, and then focused pushing is used for a short periodto expel the fetus from the birth canal.

DocumentationClear and complete documentation on the woman’s mon-

itor strip is started before the initiation of monitoring andconsists of identifying information plus other relevant data.This documentation is continued and updated according toinstitutional protocol as monitoring progresses. In some in-stitutions, observations noted and interventions implementedare recorded on the monitor strip to produce a comprehen-sive document that chronicles the course of labor and the carerendered. In other institutions this documentation is confinedto the labor flow record or computer chart. Advocates of doc-umenting on both the medical record and the EFM strip citeas advantages of this approach the ease of writing directly onthe strip while at the bedside or inputting the data on acomputer-based documentation system and the improved ac-curacy in documenting critical events and the interventionsimplemented. Others believe that charting on the EFM stripconstitutes duplicate documentation of the same informationnoted in the medical record, and thus it is unnecessary ad-ditional paperwork for the nurse.

One way of documenting that frequent maternal-fetal as-sessments have been done at the bedside is either to initialthe EFM strip or to depress the “mark” button during theseassessments. Data-entry devices are now available with someEFM systems; assessments are keyed in and subsequentlyprinted on the strip. A disadvantage of documenting on boththe EFM strip and the medical record is that frequently thetimes noted for events and interventions on the EFM stripdo not correlate with what is later documented in the med-ical record. These inaccuracies can lead those involved in theretrospective review process carried out during litigation toinfer that documentation errors have occurred. Therefore if


TABLE 13-6

Types of Acidosis

BLOODGASES* RESPIRATORY METABOLIC MIXED

pH ↓ ↓ ↓(�7.1) (�7.1) (�7.1)

PCO2 (mm Hg) ↑ Normal ↑(�60) (�60) (�60)

HCO3� (mEq/L) Normal ↓ ↓

(16-24) (�16) (�16)Base Normal ↑ ↑

(�12) (�12) (�12)

Sources: Gilstrap, L. (2004). Fetal acid-base balance. In R. Creasy, R. Resnik,& J. Iams (Eds.). Maternal-fetal medicine: Principles and practice (5th ed.).Philadelphia: Saunders; Pagana, K., & Pagana, T. (2002). Mosby’s manualof diagnostic and laboratory tests (2nd ed.). St Louis: Mosby; Tucker, S.(2004). Pocket guide to fetal monitoring and assessment (5th ed.). St. Louis:Mosby.*Arterial values.



institutional policy mandates documentation on both themonitor strip and the medical record, it is critically impor-tant for the nurse to make sure the times and notations ofevents and interventions recorded in each place agree. Noone method of documentation is right; rather, the nursemust be aware of and follow individual institutional policies,as well as participate in formulating such policies (McCart-ney, 2002). Many of the aspects of care and events that can

be documented on the patient’s medical record or the mon-itor strip are listed in Box 13-5.

EvaluationEvaluation is a continuous process. The nurse can assumethat care was effective when the outcomes for care have beenachieved (see Plan of Care).

Electronic Fetal Monitoring during LaborPLAN OF CARE

NURSING DIAGNOSIS Maternal anxiety related tolack of knowledge about use of electronic monitor

Expected Outcomes The patient will exhibit in-creased understanding about fetal monitoring andsigns of reduced anxiety (i.e., absence of physicalindicators, absence of perceived threat, and ab-sence of feelings of dread).

Nursing Interventions/Rationales

• Explain and demonstrate to woman and labor support part-ner how the electronic monitor (internal or external) worksin assessing FHR and in detecting and assessing quality ofuterine contractions to remove fear of unknown and ensurethat woman can move with the monitor.

• When making adjustment to the monitor, explain to the cou-ple what is being done and why, to promote understandingand allay anxiety.

• Explain that although a side-lying position or semi-Fowler’sposition provides for optimal monitoring, position changesdecrease discomfort; therefore encourage frequent changesin position (other than supine) and explain any monitoringadjustments that are being made as a result to reduce dis-comfort and allay anxiety.

NURSING DIAGNOSIS Risk for fetal injury relatedto inaccurate placement of transducers or elec-trodes, misinterpretation of results, or failure touse other assessment techniques to monitor fe-tal well-being

Expected Outcomes Fetal well-being is adequatelyassessed, and any fetal compromise is identifiedimmediately.


• Carefully follow guidelines and checklist for application andinitiation of monitoring to ensure proper placement of mon-itoring devices and production of accurate output from mon-itoring devices.

• Check placement throughout monitoring process to ensurethat devices remain correctly placed.

• Regularly assess and record results of electronic EFM (FHRand variability, decelerations, accelerations, uterine activity,

contractions, uterine resting tone) to provide consistent andtimely evaluation of fetal well-being and progress of labor.

• Auscultate FHR and palpate contractions on a regular basisto provide a cross-check on the EFM output and ensure fe-tal well-being.

NURSING DIAGNOSIS Risk for maternal injury re-lated to incorrect placement of external or inter-nal monitors or misinterpretation of contractionpattern

Expected Outcome Maternal well-being is as-sessed continuously, and any alterations are iden-tified promptly.


• Palpate uterine contractions to correlate data with electronicmonitoring results.

• Periodically recheck placement to verify that all monitoringdevices are accurately placed.

• Assess uterine activity, contraction pattern, and baseline toprovide ongoing evaluation and basis for further interventions.

• Use correct aseptic technique for insertion of internal mon-itors to prevent infection.

• Monitor maternal temperature, as well as color, odor, andamount of amniotic fluid, to determine indicators of in-fection.

NURSING DIAGNOSIS Risk for impaired physicalmobility related to restriction of movement withmonitoring devices

Expected Outcome Woman will be able to changepositions and ambulate at intervals.


• Discontinue continuous EFM at intervals to change positionand increase mobility.

• Encourage woman to change position and reposition mon-itor as needed to decrease complications of immobility.

• Place external monitor manually at intervals to collect datawhile woman is out of bed.

CD: P

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EFM, Electronic fetal monitoring; FHR, fetal heart rate.



COMMUNITY ACTIVITY

1 Prepare the class using an ethical decision modelsuch as described in the Wood article in your ref-erence list.

2 Summarize the topics you will include and iden-tify the evidence on which these topics are based.

3 Suggest questions that the women can ask theirhealth care providers about fetal monitoringchoices.

You have been asked to give a class on fetal as-sessment during labor to couples attending child-birth classes at the local clinic. The class is a mixof low and high risk patients. The objective of theclass is to provide them with information for mak-ing an informed decision about the choice betweenintermittent auscultation and electronic fetal mon-itoring.

• Fetal well-being during labor is gauged by the re-sponse of the FHR to UCs.

• FHR characteristics include the baseline FHR andperiodic changes in the FHR.

• The monitoring of fetal well-being includes FHR as-sessment, watching for meconium-stained amni-otic fluid, and assessment of maternal vital signsand UA.

• It is the responsibility of the nurse to assess FHR patterns, implement independent nursing

interventions, and report nonreassuring patternsto the physician or nurse-midwife.

• AWHONN and ACOG have established and pub-lished health care provider standards and guide-lines for fetal heart monitoring.

• The emotional, informational, and comfort needs ofthe woman and her family must be addressed whenthe mother and her fetus are being monitored.

• Documentation is initiated and updated accordingto institutional protocol.

Key Points

Fetal Monitoring1 There is not enough evidence that says there are significant dif-

ferences in infant outcomes between infants of low risk moth-ers who had EFM and infants of those who had IA of the FHR.There is some evidence that there is an increase in operative

births when EFM is used (Albers, 2001; Thacker, Stroup, &Chang, 2001).

2 a. IA is as effective in low risk and high risk women as con-tinuous monitoring. The monitoring guidelines are differ-ent. In low risk women in active labor IA is done every

Answer Guidelines to Critical Thinking Exercise

Documentation

OBSERVATIONSMaternal

• Vital signs: BP, TPR• Oxygen saturation if monitored• Uterine activity: frequency, duration, intensity, resting tone• Behavior: anxiety, irritability, fear of losing control• Breathing pattern• Position; activity (ambulating, BRP, use of birthing ball, etc.)• Rupture of membranes; time, color, amount, odor• Voidings; nausea, vomiting• Urge to push; bearing down; pushing

Fetal

• FHR, variability, periodic or episodic changes• Fetal movement• Oxygen saturation if monitored• Presentation, position, station

ADJUSTMENTS

• Relocation of transducers• Replacement of electrode

• Replacement of IUPC• Adjustment or flushing of IUPC• Testing of monitor• Monitor paper changes; time lapse• Interruption or removal of monitoring equipment

INTERVENTIONS

• Maternal position change• Administration of oxygen• Parenteral fluids; changes in flow rate• Amnioinfusion• Fetal scalp stimulation• Medication administration• Oxytocin• Analgesics• Anesthetics• Tocolytics• Primary health care provider notification, reason, and

response• Birth data

BOX 13-5

BP, Blood pressure; BRP, bath room privileges; FHR, fetal heart rate; IUPC, intrauterine pressure catheter; TPR,Temperature, Pulse, and Respirations.


30 min; in second stage—every 15 min. For high risk women,every 15 min in active labor and every 5 min in second stage.

b. There are no significant differences in infant outcomes whenthe above monitoring guidelines have been used.

c. A 1:1 nurse:patient ratio is needed for IA; EFM is routinelyused in most health care facilities because of budget and stafflimitations.

3 The priority for the nurse is to respond to Keri’s concern abouta safe outcome. Keri needs to be assured that her baby will beassessed and interventions will be implemented if nonreas-suring signs occur. Then the nurse can provide informationabout fetal monitoring methods. If IA is a choice (hospital pol-icy, health care provider approval), Keri should be given information about its effectiveness in low risk women andabout its advantages and limitations. Keri also needs to know

the difference between external and internal EFM and whyeach may be used in labor situations and the advantages andlimitations. Keri’s support persons should be included in thediscussion. The doctor or nurse-midwife is informed of Keri’srequest and what information she has received from the nurse.A decision for using EFM or IA is then made between Keri andher primary health care provider.

4 Yes, there is objective evidence to support this response to Keri.

5 Keri may not be interested in learning about IA as a method,or it may not be available. Then the nurse should provide information about EFM and its advantages and limitations so that Keri does not have a false sense of security about the birth outcome just because her baby is being monitoredwith EFM.


American College of Nurse-Midwives818 Connecticut Ave., NW, Suite 900Washington, DC 20006202-728-9860www.midwife.org

American College of Obstetricians and Gynecologists (ACOG)409 12th St., SWWashington, DC 20024800-762-2264www.acog.com

Association of Women’s Health, Obstetric and Neonatal Nurses(AWHONN)

2000 L St., NW, Suite 740Washington, DC 20036800-673-8499 (United States)800-245-0231 (Canada)www.awhonn.org

National Association of Parents and Professionals for SafeAlternatives in Childbirth (NAPSAC)

P.O. Box 267Marble Hill, MO 63764314-238-2010www.napsac.org

National Institute of Child Health and Human Development(NICHD)

National Institutes of Health9000 Rockville PikeBldg. 31, Room 2A32Bethesda, MD 20892301-496-4000www.nih.gov

Resources

Albers, L. (2001). Monitoring the fetus in labor: Evidence to supportthe methods. Journal of Midwifery & Women’s Health, 46(6), 366-373.

American Academy of Pediatrics (AAP) & American College ofObstetricians and Gynecologists (ACOG). (2002). Guidelines for peri-natal care (5th ed.). Washington, DC: AAP & AGOG.

Association of Women’s Health, Obstetric and Neonatal Nurses. (2003).Fetal heart monitoring principles and practice (3rd ed.). Dubuque, IA:Kendall/Hunt.

Bricker, L., & Neilson, J. (2000). Routine Doppler ultrasound in preg-nancy (Cochrane Review). In The Cochrane Library, Issue 2, 2004.Chichester, UK: John Wiley & Sons.

Feinstein, N. (2000). Fetal heart rate auscultation: Current and futurepractice. Journal of Obstetric, Gynecologic, and Neonatal Nursing, 29(3),306-315.

Feinstein, N., Sprague, A., & Trepanier, M. (2000). Fetal heart rate auscultation. Washington, DC: Association of Women’s Health,Obstetric and Neonatal Nurses (AWHONN).

Freeman, R., Garite, T., & Nageotte, M. (2003). Fetal heart rate monitoring(3rd ed.). Philadelphia: Lippincott Williams & Wilkins.

Garite, T., Dilday, G., McNamara, H., Nageotte, M., Boehm, F.,Dellinger, E., Knuppel, R. et al. (2000). A multicenter controlled trial

of fetal pulse oximetry in the intrapartum management of nonre-assuring fetal heart rate patterns. American Journal of Obstetrics andGynecology, 183(5), 1049-1058.

Gilstrap, L. (2004). Fetal acid-base balance. In R. Creasy, R. Resnik, &J. Iams (Eds.), Maternal-fetal medicine: Principles and practice (5th ed.).Philadelphia: Saunders.

Goodwin, L. (2000). Intermittent auscultation of the fetal heart rate:A review of general principles. Journal of Perinatal and NeonatalNursing, 14(3), 53-61.

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