Antepartum Fetal Surveillance ‘HELLO BABY, HOW ARE YOU?’ Presented By: Janet L. Smith, RNC, BSN Author: Ruth Saathoff, RNC, BSN

OBJECTIVES: At the end of this class the learner will be able to: Name 5 methods of monitoring the fetus for well-being Describe the physiology of maternal and fetal circulation in the relationship to fetal reserve. Identify the maternal and fetal conditions that indicate a need for fetal surveillance.

Indications for Fetal Evaluation Maternal risk factors Pre-existing maternal disease Exposure to teratogens in 1st trimester Substance abuse Infertility or conception within 3 months of last delivery (cont.) What risk factors can you identify that would require fetal surveillance? Pre-existing maternal disease: diabetes, lupus, asthma, cardiac, renal, seizure disorder, psychiatric, chronic UTI’s or renal disease, blood or bleeding disorders, reproductive tract anomaly, ABO/Rh sensitivity, chronic hypertension, Maternal anemia (sickle cell, thalassemia), Teratogens: from illness (rubella, Parvovirus, etc.) or dangerous drug or chemical exposure in 1st trimester. Substance Abuse: any street drug, alcohol, smoking Infertility: especially if prolonged Conception within 3 months of last delivery History of OB complication—previous or present: Incompetent cervix, Placenta previa, abruption, bleeding, PIH, HELLP, Polyhydramnios or oligohydramnios, Chorioamnionitis, PPROM, Preterm labor, multiple gestation. Isoimmunization (Rh sensitization), Previous pregnancy loss: ectopic, mole, SAB, TAB, Stillbirth, or neonata Prolonged PROM > 24 hours: at term or near term Significant stressful event during pregnancy: Loss of loved one, MVA, etc. Familial history of genetic abnormality: Downs Syndrome, Trisomy 13 or 18 Post dates: > 41 weeks Can you think of others? Weight—too little gain or obesity, grandmultiparity; age--< 16 or > 35.

Indications for Fetal Evaluation Maternal Factors (cont) History of OB complication Oligohydramnios, Gestational Hypertension, etc. Previous pregnancy loss PROM > 24 hours Familial history of genetic abnormality Post dates

Indications for Fetal Evaluation Fetal risk factors Prematurity SGA or LGA Intrauterine growth restriction (IUGR) Known anomaly History of IUFD Fetal cardiac arrhythmias Decreased fetal movement Prematurity of less than 37 weeks with contractions present SGA or LGA IUGR Known anomaly: cardiac; renal; structural IUFD: suspected Fetal cardiac arrhythmias as heard during office visit, seen on ultrasound,etc. Decreased fetal movement: THE BIG ONE—the one most often present Can you think of others: suspected breech presentation or shoulder presentation

Why and When Why do we think of a well baby in terms of placental perfusion? Oxygen & nutrients are needed for fetus Risk factors may reduce delivery to fetus Good oxygen & nutrient delivery results in movement and growth When is surveillance started? When risk is present IDDM (type 1) - 32 weeks Previous loss - 34 weeks The fetus must obtain its oxygen through a number of structures and interfaces in the placenta. At various points oxygen reduction is present with the addition of risk factors. We measure oxygen delivery by the response of the fetus. If the delivery is good, the fetus responds with movement and growth. If it is inadequate, the opposite is seen. A good response tells us the central nervous system is intact—no hypoxia. When started: When risk identified or as above for special situations. Goal: to prevent an Intrauterine Fetal Demise—but 30-50% of IUFDs occur in women with no identifiable maternal or fetal risk factors.

Patient: Kay Sarah Doc: I. Ben Cursed M.D. G 2 P1-0-0-0 Previous stillbirth @ 39 weeks Present gestation is 37 weeks Has been keeping a Fetal Activity Diary (FAD) since 36 weeks Now to begin surveillance with weekly NST FIRST: go to next slide and talk about FAD

Fetal Movement Counts FM indicator of intact Central Nervous System function First line defense to identify the fetus in trouble 30-50% of IUFD occur in women with no identifiable risk factors FAD Generally want 10 movements in 12 hours; most feel 10 in a few hours. Rationale:fetal motor activity is reflective of functional changes in the central nervous system, which may signal deterioration of fetal health. When adequate movements present, it indicates an intact nervous system and no hypoxia.

Methods for Fetal Movement Counts Count-to-ten Counting after meals Evening monitoring Also called KICK COUNTS Count-to-ten: At. the same time of each day begin to count fetal movements. Document the time of day and the time when 10 movements have been noted. Usually less than 2 hours. After meal counting--pt. evaluates fetal movement for 3 30-60 min. periods each day. 4 or more fetal movements should be felt during each period. 4 movements/1 hour = reassuring. Evening monitoring--maximum fetal activity period is from 7:00 p.m.-11:00 p.m. Pt. to monitor fetal movements until 10 are felt. Pro’s: Patient has sense of responsibility, validity, control; noninvasive; can be done anywhere. Inexpensive, reassuring, easy to teach. Con’s: It’s subjective; anxiety involved; not reliable as sole indicator of fetal well-being if fetal risk factors present For most at-risk, initiate at 32-34 weeks Reasons for decreased fetal movement: fetal sleep, smoking, lack of eating, medications, time of day, gestational age (<37 weeks, less space), placental location.

Interpretation Report when criteria not met Report no movement over 8 hours Report sudden violent increase in fetal activity followed by cessation of movement Report changes in normal pattern of fetal movement National standard is that if a fetus has not moved in 12 hours, it is at serious risk for fast deterioration. The 37 weeker who calls to say her baby doesn’t kick the same as before--less room.

Non-stress Test (NST) Fetal movement typically accompanied by FHR accels when CNS intact and with adequate oxygenation Procedure: Position sitting, semi-Fowler’s with tilt to either side Good quality EFM tracing for 20-40 min May monitor up to 60 min Rationale: Fetal movement is typically accompanied by FHR accels in fetus with intact CNS and adequate oxygenation. Procedure; Leopold’s maneuvers to identify back. Test monitor for accuracy. Inform patient of procedure Document on monitor strip :NST begun” If RNST: plan, teach, schedule, report, and document if NRNST: reposition, stimulate baby, explore reasons (diet, recent nicotine, etc.), continue to monitor up to 60 minutes. Multiple gestations: Careful assessment & documentation of method used to ascertain separate babies. Monitors that can do two external babies, have lights that flash. If flashing at the same time, same baby.

Interpretation What to look at (5 parameters) Assessment What’s the baseline? Is there variability present? Any uterine activity present? Any accels present? Any decels present? Assessment

Baseline Variability Accelerations Decelerations Uterine Activity Fetal Movement

Interpretation Reactive: 2 accels in 20 min. 15 bpm X 15 sec. 15 sec. from start of accel to end of accel 15 bpm at apex of accel gestation < 32 weeks 10 bpm X 10 sec. frequent decels of 10-20 sec. Might mention at frequent decels of 10-20 sec. on a term baby usually means low amniotic fluid. 24-28 weeks—frequently nonreacive 28-32 weeks—50% may not be reactive

Interpretation Nonreactive: does not meet above criteria if not reactive in 60 min. unlikely to become so; call HCP isolated decels seen in as many as 33% Causes of nonreactive tracing: Indicates a need for further testing Sleep immature CNS cigarettes fetal hypoxia and acidosis meds Spontaneous variable decels: further assessment of amniotic fluid volume recommended Assessment of cord placement/position/integrity “In a reactive tracing with good baseline variability, isolated decelerations which are < 15 beats from the baseline rate lasting<15 - 30 sec. following an acceleration do not signify fetal compromise.” James, DK et al. High Risk Pregnancy Management Option. Saunders. 1995 Reassuring or non-reassuring: If reassuring, < 1% chance of fetal death within 1 week of test.

Example at term

Example 31 weeks

Back to Ms. Sarah Her NST is reactive Anything else? Chart the 5 parameters on strip & chart Call HCP and report Schedule next appointment Continue FAD Review the 5 parameters: baseline variability present uterine activity present accels present decels present

Retesting If no risk factors, unlikely to have FD in one week With risk factors, repeat 2 times a week If pregnancy status changes, repeat in 24-48 hours If no diagnosis of pregnancy risk factors: unlikely to have FD within one week of RNST If DM or IUGR or postdates repeat q 2-4 days If changes in pregnancy pattern, repeat in 24-48 hours Advantages: Non-invasive; established reliability and guidelines, very low false-reactive results (7:1000) Disadvantages: Not definitive for stress/distress, Moderate false-nonreactive-- many are just ‘laid back babies or sleeping.

Patient: Ms. Hertzelot Doctor: I. Ben Cursed M.D. 37 weeks gestation G1 P0 Has not felt baby move for 8 hours Please do NST

Assessment NST: Non-reactive after 40 min Possible causes: fetal sleep smoking before coming Maternal medications immature CNS fetal hypoxia

Well, now what? Juice myth Do Fetal Acoustic Stimulation Test (FAST) Usually elicited after 28 weeks Can be done after 10 min of non-reactive pattern Handheld device generates a low frequency (82 decibels) vibro-acoustic stimulus Apply for 3-5 sec avoiding fetal head; may repeat X 2 at least 1 min apart May cause some level of stress Definition: A handheld device which generates a low frequency vibro-acoustic stimulus directed towards the fetus to improve the efficiency of the NST. Rationale: Studies indicate it is probably at least as reliable as NST; provides some level of stress It’s a startle response in utero if intact CNS (Nyman, Barr, & Westgren – 1992 “no adverse effects as of 4 years of age) It’s “a useful way to reduce the number of non-reactive tracings and shorten testing time.” James Procedure: Instruct patient

Results of FAST Causes ‘Moro’ or startle reflex if CNS intact Increase in FHR 1 accel of 15 bpm over 2 minutes 2 accels of 15 bpm for at least 15 sec within 5 minutes of test Useful way to reduce number of non-reactive NST's Shortens testing time Advantages: Non-invasive Quick Low false-reactive Disadvantages same as for NST Not as widely accepted as NST Moderate false-nonreactive results

Vibroacoustic Stimulation

Back to Ms. Hertzelot Well, now what? NST reactive with FAST Monitor until BL is restored Home with FAD Document on Strip and Chart Reactive FAST can be a long return to baseline.

Patient: Ms. Shirley I. M. Late Doctor: I Ben Cursed M.D. 40 & 5/7 weeks gestation Please do NST Results: NST: non-reactive FAST (or VAS): still non-reactive More monitoring: still non-reactive

Well, now what? Options: Contraction Stress Test (CST) assumes uteroplacental insufficiency will show hypoxia with late decels with contractions Biophysical Profile (BPP) Ultrasound assessment of acute and chronic markers show good predictor of fetal well-being

CST Modes Nipple stimulation (BST) IV oxytocin (OCT) may be poorly received by patient noninvasive IV oxytocin (OCT) requires invasive procedure Spontaneous contractions Rationale: Based on assumption that fetus with uteroplacental insufficiency will show hypoxia with late decelerations in response to UC’s.

Interpretation FHR response to stress of contractions 3 contractions lasting 40-60 sec. in 10 min. ‘Negative’ is absence of late decels (That’s good!) ‘Positive’ is presence of late decels (That’s bad!) > 50% of contractions--need to deliver ‘Equivocal’ is presence of some lates <50% of contractions Hyperstimulation or Unsatisfactory Results Considered testing failure and are not clinically useful ‘Suspicious’ Variable Decelerations Advantages: Tests fetal response tolerate stress Familiar, accepted Low false-negative Disadvantages Nipple stimulation. May be poorly received by patient Oxytocin requires invasive procedure Need setting with C?S capabilities Uterine activity may be difficult to control or lead to uterine hyperstimulation or PTL Replaceable by less potentially harmful tests, esp. FAST

Negative Positive – Late Decelerations Suspicious – Variable Decelerations Test Failure - UterineTachysystole

BPP Parameters Need high tech equipment/skilled technician Fetal Tone (FT) (7-8wks) Fetal Movement (FM) (9wks) Fetal Breathing Movements (FBM)) (20-21wks) Amniotic Fluid Index (AFI) > 6 cms NST (Accelerations 30-32 wks) Need high tech equipment/skilled technician Non-invasive, highly predictive Rationale: Ultrasound assessment of acute and chronic markers show good predictor of fetal well-being. Procedure: prolonged ultrasound (20-30 min) plus NST Advantages: Non-invasive Reliable and highly predictive in high-risk and prolonged pregnancy Secondary findings of anomalies possible Disadvantages Need high-tech equipment Need skilled technician Time required Modified BPP—NST and AFI (greater than 5 cms of fluid in 4 quadrant pockets)

Scoring Biophysical Variable Normal (Score = 2) Abnormal (Score = 0) Fetal breathing movements 1 or more episodes of ≥ 20 s within 30 min Absent or no episode of ≥ 20 s within 30 min Gross body movements 2 or more discrete body/ limb movements within 30 min (episodes of active continuous movement considered as a single movement) <2 episodes of body/limb movements within 30 min Fetal tone 1 or more episodes of active extension with return to flexion of fetal limb(s) or trunk (opening and closing of hand considered normal tone) Slow extension with return to partial flexion, movement of limb in full extension, absent fetal movement, or partially open fetal hand Reactive FHR 2 or more episodes of acceleration of ≥ 15 bmp* and of >15 s associated with fetal movement within 20 min 1 or more episodes of acceleration of fetal heart rate or acceleration of <15 bmp within 20 min Qualitative AFV 1 or more pockets of fluid measuring ≥ 2 cm in vertical axis Either no pockets or largest pocket <2 cm in vertical axis

Interpretation Scoring 10 point scale (if performed with a NST) 8-10 indicates fetus in good condition 6 indicates need to repeat in 4-6 hours <6 indicates need for delivery AFI < 6 cms indicates delivery See handout

Back to Ms. Late Well, now what? NST: non-reactive CST: negative BPP: 6/10 (FT-2, FM-2, FBM-0, AFI-2, NST-0) Report to HCP/document all findings Home with FAD Reschedule for repeat NST/BPP in 2-3 days

Other Surveillances Amniocentesis Ultrasound Examination Fetal lung maturity Testing- genetic, cultures, change in optical density Ultrasound Examination Uterine contents Fetal biometry / dating Fetal anatomic examination Amniocentesis: Gives knowledge of maturity of fetal lung aids in optimizing delivery time in at-risk pregnancies. Done at 15-17 weeks for genetic testing. Done in HCP office most often. Procedure & Nursing role: Pt. teaching, give Terbutaline as ordered to relax uterus, prepare sterile tray, etc., prepare specimens to block light and send to lab., give Rhogam if indicated, wedge hip to prevent supine hypotension. Lung profile: L/S ratio (Lecithin/sphingomyelin) 2:1 at term--not reliable in diabetics, meconium or blood in fluid alters ratio PG positive after 35 weeks. Not affected by diabetes, not affected by fluid contamination, can use vaginal pool specimen, but 25T of mature fetuses do not produce PG Amniotic fluid creatinine level > 2mg/dl for maturity of renal system Advantages: Reasonable reliability to lung maturity Disadvantages: Invasive, Pt. anxiety, risks of ROM and /or infection, risk of placental perforation, risk of fetal puncture. Ultrasound Level II: Complete review of systems, serially done for growth curve. Dating/EDD before 20 weeks, estimate fetal weight, look for symmetrical growth, anomalies,, Down’s syndrome. Non-invasive, but time consuming. Cost.

Other Surveillance Options Doppler Flow Studies Checks BP of uterine and placental vessels Associated with fetal growth deficiency Doppler flow Studies: movement of blood in vivo based on the change in frequency of reflected sound. What checked: Abnormalities in UA blood velocity associated with fetal growth deficiency fetal vessels, such as aorta and in brain, show fetal hemodynamic responses to physiologic and pathologic events Maternal uterine artery blood flow, placenta implantation site, subplacental vessels. Technique: transvaginal, or transabdominal Used to assess or aid with screening in: fetal growth deficiency fetal hypoxia fetal anemia pre-eclampsia These abnormal waveforms are associated with histological evidence of reduced numbers of small placental blood vessels and therefore reflect "placental insufficiency". In pregnancies with reduced, absent or reversed end-diastolic velocity, there is an increased risk of stillbirth, asphyxia, chromosomal and congenital abnormality. Abnormal umbilical Doppler waveforms can be present for weeks before there is evidence of fetal compromise and therefore are a marker of a high risk situation and should not normally be used in isolation as an indication for delivery. However, most obstetricians would consider delivering a fetus with absent end-diastolic velocity from about thirty two weeks gestation following administration of corticosteroids. In many instances, fetuses with absent end-diastolic velocity would present much earlier in pregnancy and may require extremely preterm delivery.

Other Surveillance Options (cont’d) Chorionic Villus sampling early prenatal genetic studies Chorionic Villus Sampling Rationale: Provides earlier prenatal diagnosis than amniocentesis Available since 1983 The chorionic villus sample can be collected by putting a thin flexible tube (catheter) through the vagina and cervix into the placenta. The sample can also be collected through a long, thin needle put through the belly into the placenta. Ultrasound is used to guide the catheter or needle into the correct spot for collecting the sample

References: American Academy of Pediatrics, American College of Obstetricians & Gynecologists, Guidelines for Perinatal Care (5th ed. 2002), Antepartum surveillance, pp. 89-107. AWHONN Fetal Heart Rate Monitoring Principles and Practices 4th Ed. Christensen FC, Olson K, Rayburn WF (2003). Cross-over trial comparing maternal acceptance of two fetal movement charts. Journal of Maternal-Fetal and Neonatal Medicine, 14(2), pp. 118-122. Devoe, L, Glob. libr. women's med., (ISSN: 1756-2228) 2008; DOI 10.3843/GLOWM.10210 Martin, E.J., Intrapartum Management Modules (3rd ed. 2002), Performing fetal surveillance testing, pp. 411-413. Mattson, S., Smith, J.E., Core Curriculum for Maternal-Newborn Nursing (3rd. ed.,2004), Clinical practice pp. 165-166. Simpson, K. R., Creehan, P.A., Perinatal Nursing (2nd ed., 2001), Fetal surveillance, pp. 147-154.