ABNORMALITIES OF AMNIOTIC FLUID

PRESENTED BY DR PUSHPA RAI

Outline

Normal amniotic fluid

Definition (poly hydro& oligo hydro) Etiology

Diagnosis

Sign &symptoms

Complication

Treatment Prvention

AMNIOTIC FLUID

• ORIGIN*1-IN EARLY PREGNANCY-ultrafiltrate of maternal plasma. .2-BY BEGINNING OF SECOND TRIMESTER-it largely consists of ECF which diffuse through fetal skin .3-AFTER 20 WKS OF GESTATION-it largely consists of fetal urine(d/t cornification of fetal skin no diffusion.

INFLOW

(1000 ml/d)

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1.FETAL URINE

2.LUNG LIQUID

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INTRAMEMBRANOUS -(placenta,cord)

TRANSMEMBRANOUS-(amniotic membranes)

RECYCLING – 3hrs

OUTFLOW

(1000 ml/d)

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1.FETAL SWALLOWING

AMNIOTIC FLUID VOLUME

• WKS OF GESTATION 16 wks 28-30 wks 36 wks 38 wks 40 wks 42 wks

• A.F. VOLUME 2OOml 1OOOml 1OOOml 9OOml 8OOml 2OOml

Physical features…

• Ph-( 7 – 7.5). S.G-(1.010). Osmolarity(250 m Osmol / lit. is suggestive of fetal maturity) it becomes highly hypotonic to maternal serum at term. COLOUR-in early preg .colourless. Near term-pale straw coloured.

CONT…

• ABNORMAL COLOUR- (1)-Green-(meconium stained)-Fetal distress ( 2-) Golden-Rh incompatibility (3)-Greenish yellow(saffron)-post maturity. (4) Dark brown- IUD

FUNCTIONS OF AMNIOTIC FLUID

*Shock absorber – protects from external trauma.

*Protects cord from compression.

*Permits fetal movements – development of musculoskeletal system, prevents adhesions.

*Maintenance of fetal body temperature.

*Some fetal nutrition, water supply.

*Bacteriostatic properties.

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ABNORMALITIES OF A.F

• 1-POLYHYDRAMNIOS & 2-OLIGOHYDRAMNIOS

POLYHYDRANIOS

• It is the presence of excessive amount of liquor >2 L ,0r (AFI >25),or a largest vertical pocket of fluid measuring >8cm.

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VARIETIES:

• ACUTE: AT 4^TH OR 5^TH M fluid accumulates rapidly in few days. Symptoms are severe as rate is rapid and uterus is distended rapidly. Pregnancy ends before 28w.

It is common with monozygotic twins.

It is an OBSTERICAL EMERGENCY.

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• CHRONIC : More common and appears in the sec half of pregnancy. The rate of collection is slow so uterus may reach a bigger size than acute type but symptoms are not so severe.

�,or

CONT..

• CHRONIC-Onset( taking few wks) MILD- A Vertical pocket of 8-11cm in (80%)of pt. MODERATE-12-15cm in(15%). SEVERE- >16cm in (5%).

Cont..

• ….

Etiology

1- 2-

Excessive production

Decrease uptake

FETAL CAUSES

Anencephaly(50%)

Spina bifida

Monozygotic twins(TTTS)

Rh problem

Macrosomia

MATERNAL CAUSES

DM (30%)

RENAL D

CARDIAC D

PRE-ECLAMPSIA

FETAL CAUSES

Duodenal atresia Facial clefts

Pyloric obstruction

Intestinal obstruction

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CONT…

3.Idiopathic -65%( in two third of the cases the cause is unknown. 4.Placental causes-1%(chorioangioma of placenta).

SPINA BIFIDA

ANENCEPHALY

ANENCEPHALY

IUFD

SYMPTOMS

• ACUTE: severe distressing pain that necessitates terminations of pregnancy (rare type).

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SYMPTOMS

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CHRONIC : more common and symptoms are gradual and tolerable due to slow rate of distension. When there is marked increase in the intra-abdominal P:

• Dyspnea and palpitation (raising the diaphragm) especially when lying down
• Edema and vericose.v. in the lower limbs (P on the pelvic veins)
• Easy fatigability
• Marked abd enlargement.

ABDOMINAL EXAMINATION.

• INSPECTION-Abd. Is enlarged, globular,with fullness of flanks. The skin is tense,shiny with large striae. PALPATION-Ht. of Ut.>pd.of amenorrhoea . Fluid thrill all over the Ut. Fetal parts&position/presentation cannot well defined . AUSCULTATION-F.H.S. not heard(can be heard by doppler)

INTERNAL EXAMINATION..

• The cx. Is pulled up, may be partially taken up or may dilated to admit a finger through which tense bulged membranes can be felt.

OLIGOHYDRAMNIOS

AFI<5

POLYHYDRAMNIOS

AFI>24

INVESTIGATIONS

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• US:
• CONFIRM DIAGNOSIS ???Large echo free pockets
• Diagnosis of multiple pregnancy
• Diagnosis of congenital anomalies as anencephaly, spina bifida, pyloric obstruction and duodenal atresia.
• Diagnosis of presentation and placental size and site
• Macrosomia

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• BLOOD-ABO Rh Blood sugar(PP&GTT). AMNIOTIC FLUID-Estimation alpha feto prot. (elevated in NTD.of fetus -KARIOTYPING-

D/D

• 1.TWINS . 2.PREG.WITH HUGE OVARIAN CYST. 3.MATERNAL ASCITS.

COMPLICATIONS

PREGNANCY

• MATERNAL EXHAUSTION
• PRE-ECLAMPSIA
• MAL PRESENTATION
• PREMATURE LABOUR (PMR)

LABOUR

• PRM
• CORD PROLAPSE
• CORD PRESENTATION
• UTERINE INERTIA (OVERDISTENSION)
• ATONIC PPH
• ACCIDENTAL Hg(sudden evacuation of uterus )
• -OBSTETRICAL SHOCK

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CONT..

• PUERPERIUM-1.Subinvolution 2.increased puerperal morbidity (d/t infection &blood loss)

Fetal risks:

High perinatal mortality rate ranging from 10%- 30% which is largely due to:

1.Congenital malformations.

2.Prematurity.

3.Fetal hypoxia secondary to cord prolapse, placental abruption and uteroplacental dysfunction.

MANAGEMENT

• PRINCIPLES-(1)TO RELIVE SYMPTOMS. (2)TO FIND OUT CAUSE. (3)TO AVOID& TO DEAL WITH THE COMPLICATION.

CONT….

• DURING PREGNANCY:
• Bed rest for few days.
• Mild and moderate cases follow-up with special care to BP, Bl glucose level , exclusion of NTDs (>alpha-fetoproteins) , pre-eclampsia and DM
• Semi-sitting position to avoid respiratory compression.
• Severe cases need repeated amniocentesis to relieve the tension under aseptic technique
• Acute cases (TERMINATION OF PREGNANCY)

CONT…

• NO FETAL ABNORMALITY—Maternal distress++ ---< 37wk ---AMINOREDUCTION (till fetal maturity). >38WKS ---Aminoreduction (correction of lie) ---- Oxytocin drip----ARM (controlled)----Delivery .FETAL ABNORMALITY---Deliver irrespective of gestation

CONT…

• SUPPORTIVE THERAPY—Indomethacine (25mg every 6hr )----Decrease A.F as it reduces fetal urine output.

OLIGOHYDRAMNIOS

OLIGOHYDRAMNIOS

• DEFNITION:

It is the presence of scanty amount of liquor amnii at or near term(<200ml),(AFI<5),& max.vertical pocket of liquor <2cm.

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ETIOLOGY:�

• DEFICIENT PRODUCTION

• RENAL AGENESIS (POTER’S Syndrome)
• Urinary tract obstruction as urethral valve or stricture or ureteric obstruction
• Defects in amniotic M with chronic leak
• Post-maturity

FETAL CAUSES

• MATERNAL CAUSES
• Placental insufficiency as with:
• Pre-eclampsia
• Essential hypertension
• Chronic nephritis
• Idiopathic

FETAL

PROM (50%)

CHROMOSOMAL ANOMALIES

CONGENITAL ANOMALIES

IUGR

IUFD

PLACENTAL

CHRONIC ABRUPTION

TTTS

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DRUGS

PG SYNTHETASE INHIBITORS

ACE INHIBITORS

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IDIOPATHIC

Cont.

POTER’S SYNDROME

MICRO

CEPHALY

RENAL

AGENESIS

LOW SET

EARS

IUGR

OLIGOHYDRAMNIOS

CLINICAL PICTURE

• SYMPTOMS:

“ MY ABDOMEN IS SMALL’’

“QUICKENING IS PAINFUL”

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• SIGNS:
• UTERUS<EXPECTED
• FETAL PARTS EASILY FELT
• FHS EASILY HEARD OR NOT HEARD(IUFD)

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INVESTIGATIONS

• BY US:
• To confirm diagnosis???? Amniotic pockets <2cm in the 4 quadrants of the uterus.
• To diagnose fetal anomalies and urinary tract obstruction with hydro-ureter or dilated renal pelvis or renal agenesis
• To follow-up intra-uterine fetal growth
• Decreased maternal body weight gain

FETAL COMPLICATIONS

• 1-ABORTION 2-DEFORMITIES(d/t intra amniotic adhesions--------------*Alteration in shape of skull ------------*wry neck ------------*club foot ------------* or amputation of the limb 3-fetal pulmonary hypoplasia 4-Cord compression 5-High fetal mortality

CLUBFOOT

CLUBHAND

MATERNAL COMPLICATIONS

• 1-Prolonged labour(d/t inertia) 2-Increased operative interference(d/t malpresntation) 3-increased maternal mortality

According

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- Gestational Age

- Severity

-Fetal status & well being

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MANAGEMENT

CONT…

• 1-If fetal congenital malformation----Delivery of the fetus irrespective of the pd of gestation. 2.Rehydration (increase amniotic fluid vol.) 3.Aminoinfusion

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• AMNIOINFUSION-Decreases cord compression &dilute meconium

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A procedure in which normal saline or lactated Ringer's solution is placed into the uterus after sufficient cervical opening and rupture of membranes. Amnioinfusion can treat problems associated with decreased intra-amniotic volume, including: prophylactic treatment of oligohydramnios, and to reduce the risk of meconium aspiration during labor in patients with moderate or thick meconium fluid.

AMNIOINFUSION

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Prevention

In order to prevent polyhydramnios or oligohydramnios, it would be necessary to prevent the underlying cause. Good control of maternal diabetes and the prevention of infections transmittable from mother to fetus are two approaches for a subset of cases, but, in general, prevention is not possible.

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THANK YOU