Powerpoint Templates Page 1 AMNIOTIC FLUID

Powerpoint Templates Page 2 IMPORTANT TOPICS Amniotic fluid function Clinical importance of AF Volume and composition Amniotic fluid abnormalities

Powerpoint Templates Page 3 Amniotic fluid function: Allow room for fetal growth, movement and development. Ingestion into GIT→ growth and maturation. Fetal pulmonary development (20 weeks). Protects the fetus from trauma. Maintains temperature. Contains antibacterial activity. Aids dilatation of the cervix during labour.

Powerpoint Templates Page 4 Clinical importance of AF: Screening for fetal malformation (serum α- fetoprotien). Assessment of fetal well-being (amniotic fluid index). Assessment of fetal lung maturity (L/S ratio). Diagnosis and follow up of labour. Diagnosis of PROM (ferning test).

Powerpoint Templates Page 5 Amniotic fluid formation and composition: First & early second trimester : Amount is 5-50 ml & arises from: - ultrafiltrate of Maternal plasma through the vascularized uterine decidua (in early pregnancy). - Transudation of fetal plasma through the fetal skin & umbilical cord (up to 20 weeks' gestation). * It is iso-osmolar with fetal & maternal plasma, though it is devoid of proteins.

Powerpoint Templates Page 6 Volume and composition From 20 weeks up to term (mainly - fetal urine): At 18th week, the fetus voids 7- 14ml/day; at term fetal kidneys secretes ml of urine/day into AF. - Fetal respiratory tract secretes 250ml/day into AF. - Fluid transfers across the placenta. - Fetal oro-nasal secretions. Secretion is controlled by: - Fetal swallowing at term removes 500ml/day. - Reabsorption into maternal plasma (osmotic gradient). AF constituents: - urea, creatinine & uric acid + desquamated fetal cells, vernix, lanugo hair & others→ hypo- osmolar amniotic fluid….

Powerpoint Templates Page 7 Amniotic fluid volume : About 500 mls enter and leave the amniotic sac each hour. gradual ↑ up to 36 weeks to around 600 to 1000 ml then↓ after that. The normal range is wide but the approximate volumes are: ml at 18 weeks ml at 34 weeks ml at term.

Powerpoint Templates Page 8 Amniotic fluid volume assessment Clinical assessment is unreliable. Objective assessment depends on U/S to measure: - deepest vertical pool (DVP). - Amniotic fluid index (AFI). It is a total of the DVPs in each four quadrants of the uterus. it is a more sensitive indicator of AFV throughout pregnancy.

Powerpoint Templates Page 9 Amniotic fluid abnormalities  Oligohydramnios: Defined as reduced amniotic fluid i.e. amniotic fluid index of 5 cm or less or the deepest vertical pool < 2 cm.  Polyhydramnios: Defined as excessive amount of amniotic fluid of 2000 ml or more (AFI of > 25 cm or the deepest vertical pool of > 8 cm).

Powerpoint Templates Page 10 Causes of oligohydramnios: 1. Fetal causes: * Renal cause (57%): - Renal agenesis (Potter’s syndrome). - polycystic kidney. - Urethral obstruction (atresia/posterior urethral valve). * Fetal growth restriction. * Fetal death. * Postterm pregnancy. * Preterm premature rupture membranes

Powerpoint Templates Page 11 Causes of oligohydramnios: 2. Maternal causes: Uteroplacental insufficiency. Preeclampsia. 3. Placental causes: twin-twin transfusion. 4. Drug causes: Prostaglandin synthase inhibitor as NSAID. 5. Idiopathic

Powerpoint Templates Page 12 Complications of oligohydramnios: In early pregnancy: Amniotic adhesions or bands→ amputation/death. Pressure deformities (club feet). Pulmonary hypoplasia: - Thoracic compression. - No breathing movement. - No amniotic fluid retain.  Flattened face.  Postural deformities.

Powerpoint Templates Page 13 In late pregnancy: Fetal growth restriction. Placental abruption. Preterm labour. Fetal distress. Fetal death. Meconium aspiration. Labour induction/CS.

Powerpoint Templates Page 14 Oligohydramnios:  Diagnosis: - Fundal > date. - AF I < 5CM, DVP < 2. -IUGR: abdominal circumference < 10 th centile. -Doppler abnormalities -Congenital fetal anomalies.  Management: -Treat the cause (pprom, preeclampsia). -Assess fatal wellbeing (U/S/CTG/Doppler/BPP). -Vesicoamniotic shunting (urethral obstruction). -Amnioinfusion (no↓ in fetal death).

Powerpoint Templates Page 15 Polyhydramnios

Powerpoint Templates Page 16 Polyhydramnios  types 1. Mild hydramnios (80%): a pocket of amniotic fluid measuring 8 to 11 cm. 2. moderate hydramnios (15%): a pocket of amniotic fluid measuring 12 to 15 cm. 3. Severe hydramnios (5%) - twin-twin transfusion syndrome : a pocket of amniotic fluid measuring 16 cm or more.

Powerpoint Templates Page 17 Causes of polyhydramnios Fetal malformation: - GIT: esophageal/duodenal atresia, tracheoesophageal fistula. - CNS: anencephaly (↓swallowing, exposed meninges, no antidiuretic hormone). Twin-twin transfusion → fetal polyuria. Hydrops fetalis: congestive heart failure, severe anaemia or hypoproteinemia → placental transudation diabetes mellitus (osmotic diuresis). Idiopathic.

Powerpoint Templates Page 18 diagnosis of polyhydramnios Symptoms: - dyspnea. - edema. - abdominal distention - preterm labour. Abdominal examination: - ↑uterus than expected. - difficult to palpate fetal parts. - difficult to hear fetal heart sound. - ballotable fetus. Ultrasound: - excessive amniotic fluid. - fetal abnormalities.

Powerpoint Templates Page 19 management Minor degrees: no treatment. Bed rest, diuretics, water and salt restriction: ineffective. Hospitalization: dyspnea, abdominal pain or difficult ambulation. Endomethacin therapy:. - impairs lung liquid production/enhances absorption. - ↓fluid movement across fetal membranes. * complications: premature closure of ductus arteriosus, impairment of renal function, and cerebral vasoconstriction. So not used after 35 weeks Amniocentesis: to relieve maternal distress and to test for fetal lung maturity. Complications: ruptured membrane, chorioamnionitis, placental abruption, preterm labour.

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