Amniotic Fluid powerpoint presentation 2023

amniotic fluid

1. AMNIOTIC FLUID Facilitator: Prof Ogutu Group 1 Dr Willis Ochieng Dr Phoebe Mukora Dr Wardat Abdulrauf Dr Fabrice Shimwa Dr Maureen Olita 28/10/2023 00:00 1

2. Outline Definition Anatomy, Physiology, Biochemical C omposition & Function Clinical Importance Amniotic Fluid Disorders 28/10/2023 00:00 2

3. Definition Amniotic fluid – fluid within the amniotic sac whose main function is to protect the fetus Amniotic sac – fluid filled extracelomic cavity which eventually becomes the amniotic cavity 28/10/2023 00:00 3

4. Production & Circulation The origin of the amniotic fluid is probably of mixed maternal and fetal origin Water in the amniotic fluid is replaced in every 3 hours A mniotic fluid is primarily cleared by fetal swallowing of about 500-1000 ml and transudation into the maternal circulation 28/10/2023 00:00 4

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7. Amniotic Fluid Volume & Gestational Age 50 mL - 12/40 400 mL - 20/40 1000 ml - 36/40 –38/40 600 –800 ml at Term 28/10/2023 00:00 7

8. Physical Features Alkaline with specific gravity of 1.010 Hypotonic to maternal serum at term Osmolarity of 250 mOsmol/L suggests fetal maturity Osmolality falls with advancing gestation C olorless/pale straw colored/turbid 28/10/2023 00:00 8

9. Abnormal Color Meconium stained - fetal distress Golden color - Rh incompatibility Greenish yellow - post maturity Dark colored in concealed accidental hemorrhage is due to contamination of blood. Dark brown - IUFD 28/10/2023 00:00 9

10. Biochemical Composition First half of pregnancy - identical to a transudate of plasma Late pregnancy - contamination by fetal urinary metabolites Composition Includes: Water – 98 – 99% Solid constituents (organic, inorganic & suspended particles) – 1 – 2% 28/10/2023 00:00 10

11. Function During Pregnancy Protect fetus from extraneous injury Maintains an even temperature - Thermodistribution Allows space for growth and free movement of the fetus Prevents adhesion between the fetal parts and amniotic sac Negligible nutritive value but provides adequate water supply to fetus 28/10/2023 00:00 11

12. Function During Labor Cervical dilatation Prevents interference with the placental circulation so long as the membranes remain intact Guards against umbilical cord compression Aseptic and bactericidal action protects the fetus and prevents ascending infection to the uterine cavity 28/10/2023 00:00 12

13. Clinical Importance Amniotic fluid analysis NTDs L:S ratio Chromosomal Defects Induction of abortion - chemical instillation Induction of labor - ROM Amniotic fluid index 28/10/2023 00:00 13

14. 28/10/2023 00:00 14 AMNIOTIC FLUID DISORDERS

15. Polyhydramnios Liquor amnii exceeds 2000 mL Cause discomfort to patient Imaging required to establish fetal lie and presentation Sonographically: AFI > 24 cm; DVP > 8 cm Classification: Mild: DVP > 8cm – 11 cm, Moderate: DVP 12 – 15cm Severe: DVP > 16cm Reduced Incidence: Early detection and control of diabetes Rhesus isoimmunization is now preventable Genetic counseling in early months and detection of fetal congenital abnormalities with ultrasound and their termination, reduce their number in late pregnancy 28/10/2023 00:00 15

16. Etiology Fetal Anomalies anencephaly, spina bifida, esophageal/duodenal atresia, facial clefts, neck masses, hydrops fetalis and aneuploidy Chorioangioma of the placenta Increased transudation Multiple Pregnancy Maternal diabetes, cardiac or renal disease Idiopathic 28/10/2023 00:00 16

17. Clinical Subtypes Chronic Polyhydramnios Insidious onset (weeks) More apparent in 3 rd trimester 10 times more common Acute Polyhydramnios Sudden onset/few days 2 nd trimester Acute on pre existing chronic polyhydramnios A ssociation: Monozygotic twins with TTT Chorioangioma of the placenta. 28/10/2023 00:00 17

18. Chronic Polyhydramnios Symptoms: Diaphragm elevation Respiratory distress Palpitations IVC compression Pedal edema, Varicosities of the legs/vulva Hemorrhoids Signs Dyspnea state in the lying down position Evidence of preeclampsia (edema, hypertension and proteinuria) may be present 28/10/2023 00:00 18

19. Examination Markedly distended abdomen with flank fullness; tense, shiny & striae FH > GA Abdominal girth more than normal Fluid thrill present Fetal parts not well defined FHT not heard distinctly Internal Examination: cervix pulled up, admits a finger tip; tense bulging membranes 28/10/2023 00:00 19

20. Investigations Lab ABO & Rh grouping Postprandial blood sugar OGTT HBA1c MSAFP Amniocentesis AFP L:S ratio Chromosomal anomalies Hematologic disorders Sonography Congenital malformations Multiple gestation AFI Fetal presentation and lie. 28/10/2023 00:00 20

21. Differential Diagnosis Multiple gestation Pregnancy with huge ovarian cyst Maternal ascites 28/10/2023 00:00 21

22. Complications During pregnancy Preeclampsia Malpresentation PROM Preterm labor Accidental hemorrhage due to sudden escape of liquor amnii During labor Early ROM Cord prolapse Uterine inertia Increased operative delivery due to malpresentation Retained placenta Postpartum hemorrhage and shock 28/10/2023 00:00 22

23. Complications Puerperium Subinvolution Increased puerperal morbidity Infection (operative interference and blood loss) Fetal Increased perinatal mortality Prematurity Congenital abnormality Cord prolapse Hydrops fetalis Accidental hemorrhage 28/10/2023 00:00 23

24. Principles of Management To relieve the symptoms To find out the cause To avoid and to manage the complications 28/10/2023 00:00 24

25. Management Mild polyhydramnios ( DVP: 8 –11 cm) – bed rest The excess liquor is expected to diminish as pregnancy advances Severe polyhydramnios ( DVP: ≥16 cm) Admit Identify the underlying cause Manage the underlying medical disease/ complications Supportive therapy - bed rest Sulindac 200mg BD to reduce fetal urine output Indomethacin 2.2-3mg/kg/day Further management dependent on: Response to treatment Period of gestation Presence of fetal malformation Associated complicating factors. 28/10/2023 00:00 25

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27. Management Good response to treatment Await spontaneous delivery at term Unresponsive to treatment < 37/40 relieve mechanical distress by slow amniocentesis/decompression (500 ml/hr) stop when AFI < 25 cm > 37/40 Amniocentesis → drainage of good amount of liquor → to check the favorable lie and presentation of the fetus → a stabilizing oxytocin infusion is started → low rupture of the membranes is done when the lie becomes stable and the presenting part gets fixed to the pelvis 28/10/2023 00:00 27

28. Management During Labor Usual management as in twin pregnancy Internal examination after ROM to exclude cord prolapse Oxytocin infusion in case of uterine inertia M ethergine 0.2 mg given with delivery of anterior shoulder to avert PPH Examine baby for congenital anomalies Look out for retained placenta, PPH and shock 28/10/2023 00:00 28

29. Acute Polyhydramnios Symptoms (of acute abdomen) abdominal pain, nausea, vomiting Signs Ill-looking with no features on shock Edema/features of preeclampsia Fluid thrill present Abdomen tense and enlarged > period of amenorrhea Fetal parts and tones not discernible Internal examination - cervix is pulled up +/- dilatation of the os with bulging membranes Sonography Fetal anomalies/multiple gestation 28/10/2023 00:00 29

30. Management Most often, spontaneous abortion occurs In case with severe TTTS, repetitive amnioreduction until the AFI is normal, may improve the perinatal outcome Laser ablation may cure the cause of TTTS whereas amnioreduction only treats the symptoms 28/10/2023 00:00 30

31. Oligohydramnios 28/10/2023 00:00 31 Liquor amnii < 200 ml at term Sonographically: Deepest Vertical Pocket < 2 cm or AFI < 5 cm Borderline Oligohydramnios: AFI of 5 – 8 cm

32. Etiology Fetal conditions Fetal chromosomal or structural anomalies Renal agenesis Obstructive uropathy Spontaneous ROM Intrauterine infection Drugs: PG inhibitors, ACE inhibitors Postmaturity FGR Amnion nodosum Maternal conditions Hypertensive disorders Uteroplacental insufficiency Dehydration Idiopathic 28/10/2023 00:00 32

33. Diagnosis FH < GA Reduced fetal movements The uterus is “full of fetus” because of scanty liquor Malpresentation (breech) Evidence of FGR Sonographically DVP < 2 cm 28/10/2023 00:00 33

34. Complications Fetal : Abortion Deformities Pulmonary hypoplasia Cord compression High fetal mortality Maternal : Prolonged labor due to inertia Increased operative interference due to malpresentation The sum effect may lead to increased maternal morbidity 28/10/2023 00:00 34

35. Management Fetal congenital malformation refer to FMU Use of amniopatch/ amniogel to seal any point of leakage When decision for delivery is made, it should be done irrespective of the period of gestation Induce labour in cases of severe oligohydramnios, FGR, severe malformation and if lung maturity has been attained Isolated oligohydramnios in the third trimester with a normal fetus may be managed conservatively Oral administration of water increases amniotic fluid volume In labor, cord compression is common Amnioinfusion (prophylactic or therapeutic) for meconium liquor is found to improve neonatal outcome 28/10/2023 00:00 35

36. Amnion Infusion D iagnostic and therapeutic Attempts to dilute/wash out meconium Prophylaxis in oligohydramnios Treatment of variable deceleration Various amnion infusion protocols reported, mostly include 500-800 ml bolus of warm normal saline followed by continuous infusion of approximately 3ml/min (Owen, 1990; pressman 1996) 28/10/2023 00:00 36

37. References DC Dutta’s textbook of obstetrics, 8 th edition, pages 43 – 44, 246 – 251. 28/10/2023 00:00 37