APFS seminar EDITED -final.pptx..fh monitoring

Antepartum fetal surveillance

1. PGS SEMINAR ON ANTEPARTAL FETAL SURVELANCE Presenter :-Dr .Seifu Legese(MD,OBYGYN R2) Moderator:-Dr .Wakgari Oljira (MD, Asst Proff. of OBY/GYN) 5/8/2024 APFS 1

2. Outlin e Objective Introduction Indication Methods of APFT Summary Reference 5/8/2024 APFS 2

3. Objectives To decrease/prevent perinatal mortality. To prevent permanent neurologic injury. To identify fetuses at risk for intrauterine death. To intervene adverse fetal outcome . 5/8/2024 APFS 3

4. Introduction APFS is assessment of fetal wellbeing during pregnancy especially after the fetus is considered viable. Two thirds of fetal deaths occur before the onset of labor . Many antepartum deaths occur in women at risk for uteroplacental insufficiency. 5/8/2024 APFS 4

5. Introduction … Perinatal events play an important role in infant mortality . 50 % of all infant deaths occur in the first week of life, and 50% of these losses result during the first day of life 5/8/2024 APFS 5

6. Introduction… Unexplained fetal death occurs far more commonly than unexplained infant death Ideal test allows intervention before fetal death or damage from asphyxia. 5/8/2024 APFS 6

7. Introduction… Causes of antepartum fetal deaths could be:- Chronic asphyxia/placental insufficiency, Congenital malformations, Superimposed complications of pregnancy such as Rh isoimmunization Placental abruption Fetal infection Unexplained cause 5/8/2024 APFS 7

8. Fetal Deaths by Selected Causes 5/8/2024 APFS 8

9. Triple Risk Model 5/8/2024 APFS 9

10. Sequence of fetal response to stress 5/8/2024 APFS 10

11. Indications for APFS Maternal conditions Antiphospholipid syndrome Hyperthyroidism (poorly controlled) Hemoglobinopathies Cyanotic heart disease SLE Chronic renal disease Diabetes mellitus Hypertensive disorders Pregnancy-related conditions PIH Decreased fetal movement AFV abnormality IUGR Post term pregnancy Isoimmunization (moderate to severe) Unexplained fetal loss Multiple gestation 5/8/2024 APFS 11

12. Method of antepartum fetal test Early pregnancy Biochemical MSAFP Triple screen (MSAFP, hcG and unconjugated estriole) at 15-18 weeks Acethylcholiestrase Nuchal translucency Genetic testing Late pregnancy 1. Clinical SFH A bdominal girth Weight gain 2.Biochemical Serum estriole HPL 5/8/2024 APFS 12

13. cont… 3 . Biophysical Fetal movement count NST CST BPP and modified BPP Doppler velocimetry 5/8/2024 APFS 13

14. 1.Fetal movement count Fetal activity commences as early as 7 weeks’ gestation. From 20 - 30 weeks’ gestation, general body movements become organized, and the fetus starts to show rest-activity cycle. This reflect central nervous system development and maturation . 5/8/2024 APFS 14

15. Fetal movement cont… Four fetal behavioral states are described:- I. State 1F – Quite sleep state Fetus spends 25% of its time Narrow oscillation of FHR Slow FHR , reduced variability Bladder volumes rose Can last 20 min 5/8/2024 APFS 15

16. Fetal movement cont… II . State 2F- Active sleep state Fetus spends 60-70% of its time Frequent gross movt. ,wider oscillation of FHR, continuous eye movement, Increased variability and acceleration with FM Bladder volume decline Can last 40 min 5/8/2024 APFS 16

17. Fetal movement cont… III. State 3F Continuous eye movement in the absence of FM No acceleration of FHR with movement Existence is questioned IV. State IVF- awake state Vigorous body movement Continues eye movement FHR acceleration and increased variability 5/8/2024 APFS 17

18. Fetal movement cont… Fetal movement is a more indirect indicator of fetal oxygen status and CNS function. DFM is noted in response to hypoxemia. Periods of absent fetal movement become more prolonged as gestation advances. 5/8/2024 APFS 18

19. Fetal movement cont… 5/8/2024 APFS 19

20. Fetal movement… During the 3 rd TM, the human fetus spends 10% of its time making GBM and 30 such movements each hour. Period of fetal movement appears to peak b/n 9:00 pm to 1:00 am. The longest period without FM in a normal fetus was about 75 minutes. The mother able to perceive about 70% -80% of gross fetal movements. 5/8/2024 APFS 20

21. Fetal movement cont… Methods of FM counting I. The Cardiff methods Mother count FM once/day <10 movement over 2 hours is alarming . II. Sadovsky method M other count FM 2-3x daily <3 movement/one hour is alarming. 5/8/2024 APFS 21

22. Fetal movement… III. Rayburn method Count once per day for 60minutes <3 movement/1hr for two consecutive days is alarming . 5/8/2024 APFS 22

23. Fetal movement cont… Factor that affects FM Placental location Length and type of fetal movement Amniotic fluid volume Fetal anomalies Fetal state Maternal activity Medication use Fetal jeopardy 5/8/2024 APFS 23

24. Clinical management of DFM 5/8/2024 APFS 24

25. Non stress Test Most widely applied technique for antepartum fetal evaluation. In late gestation, the healthy fetus exhibits an average of 34 accelerations above the baseline FHR each hour. Require intact neurologic coupling between the fetal CNS and the fetal heart. 5/8/2024 APFS 25

26. Non Stress Test cont… At term, more than 90% of GBM are accompanied by accelerations. Absence of acceleration shows hypoxia, drug, fetal state or congenital anomalies. The longest time between successive accelerations in the healthy term fetus is about 40 minutes. The fetus may fail to exhibit heart rate accelerations for up to 80 minutes and still be normal. 5/8/2024 APFS 26

27. Schematic linkage b/n fetal movement and FHR acceleration 5/8/2024 APFS 27

28. Non Stress Test cont… Usually performed in an outpatient setting. The patient should not have smoked recently. In most cases, only 10 to 15 minutes are required. The pt may be seated in a reclining chair, tilted to the left and PB measured. Fetal activity may be recorded and FHR is monitored. 5/8/2024 APFS 28

29. Fetal Heart Rate Patterns seen in NST 5/8/2024 APFS 29 NST Reactive (Normal) NST Nonreactive NST Base line FHR 110-160 bpm Bradycardia <100bpm Tachycardia >160bpm Erratic base line Variability 6-25bpm ≤5bpm for ≥80 minute >25bpm for > 10minute sinusoidal Deceleration No deceleration Variable or late deceleration Acceleration ≥ 2 acceleration of ≥ 15 bpm last for 15sec in 40minut ≤2 acceleration of ≤15bpm lasting ≤15 sec in ≥40 minute Action Retest optional based on clinical picture Extend test time Use of VAS Urgent action or further tests

30. Non Stress Test cont… 5/8/2024 APFS 30

31. Non Stress Test cont… Most studies have employed an electronic artificial larynx that generates sound pressure levels measured at 1 m in air of 82 dB with a frequency of 80 Hz and a harmonic of 20 to 9000 Hz. 5/8/2024 APFS 31

32. Clinical management of NST 5/8/2024 APFS 32

33. Predictive Value of the NST The NST is most predictive when it is normal or reactive. The reported false-negative rate over multiple studies ranges 0.2% - 0.8%, corresponds to a fetal death rate of 3-8 per 1000 within 1 week of a reactive NST. The false-positive rate is considerably higher ( 50% to more than 90%) in various studies. 5/8/2024 APFS 33

34. CONTRACTION STRESS TEST K nown as the oxytocin challenge test (OCT). The first biophysical technique widely applied for antepartum fetal surveillance. Uterine contractions produced a reduction in blood flow to the intervillous space. The response of the fetus at risk for uteroplacental insufficiency to uterine contractions formed the basis for this test. 5/8/2024 APFS 34

35. CST… 5/8/2024 APFS 35

36. CST… Contraindications to the test include Conditions associated with an increased risk of preterm labor and delivery, Conditions associated with an increased risk of uterine rupture, Conditions associated with an increased risk of uterine bleeding. 5/8/2024 APFS 36

37. How to do CST Conducted in an inpatient setting. Patient placed in the semi-Fowler's position at a 30- to 45-degree angle with a slight left tilt. Maternal BP measured every 5-10 minute. Base line FHR and uterine contractions are monitored for 10-20 minute. 5/8/2024 APFS 37

38. CST… Adequate CST require Uterine contraction of moderate intensity Frequency of 3 in 10 minute lasts for 40-60 second If uterine activity is absent or inadequate, nipple stimulation is or intravenous Oxytocin is begun. After the CST has been completed, the patient should be observed until uterine activity has returned to its baseline level. 5/8/2024 APFS 38

39. Interpretation of test result Negative: 80% of tests No late or significant variable decelerations any where on the tracing. Positive: 3-5% of test Late decelerations with at least 50% of contractions . Suspicious/ Eqeuvocal : 5% of tests Intermittent late or variable decelerations . 5/8/2024 APFS 39

40. CST… Hyperstimulation: 5% of tests Decelerations with contractions longer than 90 seconds’ duration or a greater than 2-minute frequency. Unsatisfactory: 5% of tests Fewer than three contractions per 10 minutes or an uninterruptable tracing. 5/8/2024 APFS 40

41. CST… Factor causing false positive CST Misinterpretation of tracing Supine hypotension Uterine hyper-stimulated Improvement of fetal condition after the CST Mgt of abnormal result For suspicious CST , repeat the CST. For positive result do BPP or delivery if term. 5/8/2024 APFS 41

42. Predictive value A negative CST has been consistently associated with good fetal outcome. Incidence of perinatal death within 1 week of a negative CST to be less than 1/1000. Cannot predict acute fetal compromise . High incidence of false-positive rate is the greatest limitations of this test. 5/8/2024 APFS 42

43. Biophysical profile Vintzileos principles Those parameter of BPP that develop later tends to disappear first. Fetal tone: 7.5 to 8.5 wks Fetal movement: 9 wks Fetal breathing: 20 to 21 wks NST: 24 to 28 wks (most reliable b/n 32 wks & term) PPV of the BPP is only ~50%, with a NPV > 99.9 %. 5/8/2024 APFS 43

44. Criteria for the biophysical profile scoring Component Normal (score 2) Abnormal (score 0) Nonstress test Reactive Nonreactive Fetal breathing movements ≥1 episode of breathing ≥30sec in 30 minute Continuous breathing, absent or non sustaining in 30 minute Fetal tone:  ≥1 episode of extension with return to flections Absent or slow extension with partial flections Fetal movement ≥3 discreet body/limb movement in 30 minute <3 episode of movement Amniotic fluid volume At least one SDP measuring 2 cm in two perpendicular plane No or SDP < 2cm 5/8/2024 APFS 44

45. Perinatal mortality with in one week of BPP score Test score interpretation PNM with one week with out intervention management 10/10, 8/8 8/10(normal fluid) Risk of asphyxia is rare 1/1000 No acute intervention for fetal basis 8/10(abnormal fluid) Probable chronic fetal asphyxia 89/1000 Delivery if term Antenatal steroid if <34 and intensive surveillance 6/10(normal fluid) equivocal Variable 61/100 on average Repeat test immediately and if persist :- Deliver tem fetus and repeat in 24 hr if preterm 4/10 High probality of fetal asphyxia 91/1000 Deliver by appropriate method with continuous fetal monitoring 2/10 Chronic fetal asphyxia with acute decomposition 125/1000 Deliver by cesarean section 0/10 Sever acute asphyia 600/1000 Deliver by CS 5/8/2024 APFS 45

46. Study review The effect of maternal fasting on the fetal biophysical profile Objectives: To determine fetal biophysical profile changes in women observing Ramadan with uncomplicated singleton pregnancy. Methods: Cross-sectional observational study healthy women who were observing Ramadan at 30 weeks or more of gestation were recruited as well as a non-fasting control group matched for age, parity, and gestational age. U/S examination included assessment of fetal bladder volume, fetal biophysical profile, and umbilical artery Doppler flow . 5/8/2024 APFS 46

47. Study review … Results: A total of 162 pregnant women were observed. Mean umbilical artery plasticity index, vertical amniotic pool depth, and fetal bladder volume were similar in the study and control groups. However, there was a significant difference in biophysical scores between the two groups. In the fasting group, 30 of 81 fetuses (37%) had a score of 6/8 compared with 11 of 81 fetuses (13.6%) in the control group (P0.001).All fetuses in both groups with a biophysical score of 6/8 showed no breathing movements. Conclusions: Fetal breathing movements are reduced during maternal fasting. 5/8/2024 APFS 47

48. Modified BPP Simplify the examination & ↓ the time to complete testing. Focus on those components of the profile that are most predictive of outcome. Assessment of AFV & NST appear to be as reliable a predictor of long-term fetal well-being as the full BPP The rate of stillbirth within one wk of a normal test is the same as with the full BPS 5/8/2024 APFS 48

49. Study review SDP or AFI as evaluation test for predicting adverse pregnancy outcome (SAFE trial): a multicenter, open-label, randomized controlled trial Objective:  To determine whether the AFI or SDP technique for estimating AFV is superior for predicting adverse pregnancy outcome. Methods:  multicenter randomized controlled trial including 1052 pregnant women with a term singleton pregnancy across four hospitals in Germany. Women were assigned randomly, according to a computer-generated allocation sequence, to AFI or SDP measurement for estimation of AFV. Oligohydramnios was defined as AFI ≤ 5 cm or SDP < 2 cm. The diagnosis of oligohydramnios was followed by labor induction. The primary outcome measure was postpartum admission to a neonatal intensive care unit. Further outcome parameters were the rates of diagnosis of oligohydramnios and induction of labor (for oligohydramnios or without specific indication), and mode of delivery . 5/8/2024 APFS 49

50. Study review cont… Results:  Postpartum admission to NICU was similar between groups (4.2% (n = 21) vs 5.0% (n = 25); relative risk (RR), 0.85 (95% CI, 0.48-1.50); P = 0.57). In the AFI group, there were more cases of oligohydramnios (9.8% (n = 49) vs 2.2% (n = 11); RR, 4.51 (95% CI, 2.2-8.57); P < 0.01) and more cases of labor induction for oligohydramnios (12.7% (n = 33) vs 3.6% (n = 10); RR, 3.50 (95% CI, 1.76-6.96); P < 0.01) than in the SDP group. Moreover, an abnormal cardiotocography was seen more often in the AFI group than in the SDP group (32.3% (n = 161) vs 26.2% (n = 132); RR, 1.23 (95% CI, 1.02-1.50); P = 0.03). The other outcome measures were not significantly different between the two groups. Conclusions:  Use of the AFI method increased the rate of diagnosis of oligohydramnios and labor induction for oligohydramnios without improving perinatal outcome. The SDP method is therefore the favorable method to estimate amniotic fluid volume, especially in a population with many low-risk pregnancies.  5/8/2024 APFS 50

51. Flow chart for antepartum fetal surveillance in which the NST and AFI are used as the primary methods for fetal evaluation 5/8/2024 APFS 51

52. DOPPLER ULTRASOUND Noninvasive technique used to assess the hemodynamic components of vascular impedance Abnormal flow correlated:- Histopathologically with small-artery obliteration in placental tertiary villi and Functionally with fetal hypoxia, acidosis and perinatal morbidity and mortality S/D ratio, RI and PI are the three well-known indices to describe arterial flow velocity waveforms 5/8/2024 APFS 52

53. Cont… Doppler abnormalities progress from the arterial to the venous side of the circulation 5/8/2024 APFS 53 Placental vascular dysfunction Increased UA blood flow resistance Decreased middle cerebral artery impedance followed Abnormal flow in the ductus venous

54. Umbilical Artery Velocimetry Central to the evaluation and management of the fetus with growth restriction Considered abnormal if:- S/D ratio above the 95th percentile for gestational age absent/reversed end diastolic flow 60 to 70 % of the small placental arterial channels would need to be obliterated before these abnormal result 5/8/2024 APFS 54

55. Middle Cerebral Artery Doppler velocimetry of the MCA is the primary method of detecting fetal anemia Could safely be replace amniocentesis in the management of isoimmunized pregnancies Such use of Doppler is appropriate in centers with personnel trained in the procedure 5/8/2024 APFS 55

56. Ductus Venousus Abnormal indices reflect myocardial dysfunction Routine use in surveillance of FGR is not recommended Used in the staging of TTTS Also help in monitoring fetuses with CHD and following treatment for SVT Best predictor of perinatal outcome among FGR but it is late finding 5/8/2024 APFS 56

57. Uterine Artery Helpful in assessing pregnancies at high risk of complications related to uteroplacental insufficiency. Persistence or development of high-resistance patterns have been linked to a variety of pregnancy complications. Standards technique and criteria to define an abnormal test are lacking. 5/8/2024 APFS 57

58. When to start The optimal GA to begin antenatal surveillance depends on the clinical condition The risk of intervention at a premature GA against the risk of IUFD must be considered ACOG recommends initiating testing at 32 to 34 weeks of gestation for most at-risk patients 5/8/2024 APFS 58

59. Cont… INDICATION INITIATION TEST FREQUENCY Post-term pregnancy 41 weeks mBPP Twice a week Uncomplicated twin At 32 weeks mBPP weekly Triplate or greater At 28 weeks mBPP Twice a week Oligohydramnios At diagnosis BPP Twice a week Polyhydramnios At diagnosis BPP 1 to two weeks Diabetes (uncomplicated) 32 weeks mBPP Twice a week Chronic or PIH(uncomplicated) At 32 weeks FMC/BPP twice-weekly. poorly controlled asthma 28 weeks mBPP Weekly Renal disease 30-32 weeks mBPP Once to two wise weekly Substance abuse 32 weeks mBPP Weekly Prior stillbirth 32-34 wk or At least 1 weeks before prior fetal death mBPP Once to two wise a week SLE 26 WEEKS mBPP Weekly IUGR At diagnosis mBPP/ doppler Twice a week Decreased fetal movement At time of complaint mBPP PRN 5/8/2024 APFS 59

60. Summary The aim of antenatal fetal surveillance is to decrease/prevent perinatal mortality and permanent neurologic injury Many antepartum deaths occur in women at risk for uteroplacental insufficiency. Ideal test allows intervention before fetal death or damage from asphyxia 5/8/2024 APFS 60

61. Cont… The CST and NST has a low false-negative rate but a high false-positive rate Use of VAS for a nonreactive NST or equivocal BPP does not increase the false-negative rate and may reduce the likelihood of unnecessary obstetric intervention multiple parameters of well-being are better predictors of outcome than any single parameter 5/8/2024 APFS 61

62. Reference Gabe Obstetrics , normal and problem pregnancies , 8th Edition section 27, antepartum fetal evaluation Williams Obstetrics, 26 th Edition page, section7 fetal patient ACOG Antepartum fetal surveillance, Practice Bulletin No. 229, May 2021a Up To date 2023 Creasy & Resnik’s maternal fetal medicine 9 th edition, section 32, assessment of fetal health RCOC green-top guideline No. 57, reduced fetal movement Cross JH, Eminson J, Wharton BA.Ramadan and birth weight at full term in Asian Moslem pregnant women in Birmingham.Arch Dis Child 1990;65(10 Spec No):1053 –1056 . Phelan JP, Smith CV, Broussard P, Small M. Amniotic fluid volume assessment withthe four-quadrant technique at 36 – 42 weeks’ gestation.J Reprod Med1987;32:540 – 542 5/8/2024 APFS 62

63. 5/8/2024 APFS 63 THANK YOU!!