Introduction

•           Pre-eclampsia is the new onset hypertension and eitherproteinuria or end organ dysfunction after 20 weeks of gestation in a previously normotensive woman.

·       It is a multisystem progressive disease and delivery results in resolution of the disease.

·       It contributes significantly to maternal and perinatal mortality and is responsible for 13% maternal deaths worldwide.

Incidence

Varies from 5 to 10% Definitions

·       Hypertension is defined as a bp measurement of more than or equal to 140/90 mm of hg or an increase in mean arterial bp { 1/3 systolic bp + 2/3 diastolic bp

} of 20 mm hg taken on two occasions atleast 6 hours apart.

·       Bp is measured in sifting or lateral lying down position with manometer at the level of heart and korotkoff phase v (disappearance of sounds) is used.

·       Proteinuria is the presence of a total proteins in 24 hours urine of 300 mg or more or 1 + or more on dipstick random samples.

·       Edema has been abandoned as a diagnostic criterion as it occurs in many normal pregnant women.

Classification

There are 5 types of hypertensive diseases that complicate pregnancy rate

1)      Gestational Hypertension

•       BP       140/90 mm Hg for first time during pregnancy No proteinuria

•       BP returns to normal before 12 wks post partum

•       Final diagnosis made only post partum

•       May have other features of preeclampsia like epigastric discomfort or thrombocytopenia

2)       Pre eclampsia

•       BP >- 140/90 mm Hg after 20 wks gestation

•       Profeinuria > 300 mg/24 hrs or> 1 + dipstick

•       Definitive criteria are

•       BP>160/llO mm Hg

•      Proteinuria 2.0 mg/24 hrs or > 2+ dipstick

•       Serum creatinine        1.2 mg/dl unless known to be previously elevated

•      Platelets <1 00000/p1

•       Micro angiopathic hemolysis -          LDH

•       Elevated serum ALT or AST

•       Persistent headache or cerebral or visual disturbances

•       Persistent epigastric pain

3)       Eclampsio

Convulsions in a case of pre eclampsia in the absence of other causes of convulsions

4)      Superimposed pre eclampsia on chronic hypertension

•      New onset proteinuria        300 mg/24 hrs in hypertensive woman but no proteinuria before 20 wks gestation

•       A sudden rise in proteinuria or BP or platelet count < 1 00000/ l in a woman with hypertension and proteinuria before 20 wks gestation

5)      Chronic hypertension

•       BP       140/90 mm Hg before pregnancy or diagnosed before 20 wks gestation not attributable to gestational trophpoblastic disease

•       Hypertension first diagnosed after 20 wks but persistent 12 wks post partum

Risk factors

•       Nulliparify

•       Extremes of age

•       Multiple pregnancy

•       Chronic hypertension

•       Obesity

•       Hydafidiform mole

•       New partner/ pregnancy with doner semen

•       Anti phospholipids antibodies

•       Diabetes or renal disease

•       Hydrops fetalis

•       Genetic predisposition

•       Previous h/o pre eclampsia

Pathophysiology

•       Basic pathophysiology is vasospasm in almost all organs which causes t peripheral resistance, bp, endothelial damage with leakage of blood constituents, platelet and fibrin deposition in subendothelial layers leading to hemorrhage, necrosis and damage to endorgans & collection of fluid in extra vascular space.

•       It affects all organs including placenta, liver, kidney, brain, retina and cardiovascular system resulting in hypoxia and iugr.

Severity of disease

•           Can be either mild or severe form

•          Indicators of severe disease are

•           Systolic bp         160 mm hg

•           Diastolic bp      110 mm hg

•           Proteinuria      3+ dipstick

•          Presence of headache , visual disturbances, epigastric or upper abdominal pain, convulsions, oliguria, pulmonary edema, obvious iugr and elevated serum creatinine, markedly elevated liver enzymes, platelet count <100000/ evidence of hemolysis are the criteria of severe pre eclampsia.

•           An apparently mild disease may progress to severe disease very rapidly.

and

•           HelIp syndrome characterized by hemolysis, elevated liver enzymes and low platelets is a feature of severe pre eclampsia.

Clinical features and diagnosis Symptoms

•           May be asymptomatic or mild swelling over ankles in the mornings or the swelling may involve face, abdominal wall and rest of the body.

•           Serious symptoms like headache, sleep disturbances, epigastric or right hypochondric pain or visual disturbances are associated with acute onset disease.

Signs

•           Rapid weight gain of more than ½ kg a week or 2 kg a month in later months of pregnancy

•           Sudden or massive generalized edema usually indicates imminent eclampsia.

•           Rise in BP

•           Basal crepts in lungs- pulmonary edema

•           Brisk tendon reflexes

•           Oligohydramnios and IUGR

•           Oliguria

Investigations

•           Complete hemogram with platelet count. The hematocrit may be raised due to hemoconcetration.

•           Coagulation profile

•           Serum uric acid – Levels > 4.5 mg/dl indicate pre eclampsia but not very useful as severe disease can occur with normal uric acid levels.

•           Blood urea maybe normal or slightly raised

•           Serum creatinine > 1 mg/dl

•           IFT - ALT, AST or LDH may be raised

•           Urine examination for proteins in 24 hrs urine and for casts

•           Fundus examination - may show constriction of arterioles or retinal edema or hemorrhages

•  

Fetal monitoring

•           Daily fetal movement count (dfmc) there should be at least 10 movements per day.

•           Clinical examination for fetal growth, presentation and well being

•           Nst ( non stress test) twice a week

•           Cardiotocography

•           Ultrasound examination should be done every 2 weeks for fetal growth, well being and amount of amnioticfluid. Nsf twice a week and bpp ( biophysical profile) once a week. Doppler studies for umbilical artery blood flow should also be done.

Complications of pre eclampsia Maternal complications

•           Eclampsia in upto 2% cases

•           Abrupfio placentae

•           Renal failure

•           Diminution of vision and blindness

•           Cerebral hemorrhage

•           Coagulation failure and dic

•           Hellp syndrome

•           Adult respiratory distress syndrome (ards)

•           Preferm labor

•           Increased operative delivery

•           Death

•           Remote complications include recurrent pre eclampsia in next pregnancy (25%), residual hypertension and chronic nephritis post partum hemorrhage (pph) and shock

•           Infection

•           Hepatic rupture

These complications can lead to maternalfetal complications

•           Iugr due to chronic placental insufficiency

•           Intra uterine asphyxia

•           Intro uterine death (iud)

•           Prematurity due to preterm labor, accidental hemorrhage or induced labor

•           Oligohydramnios

•           Placental infarction

•           Perinatal mortality is around 20%

Management Prevention

•           Low dose aspirin - it may prevent pre eclampsia by suppressing the production of thromboxane a from platelets. 75 mg daily started as early as 12 wks, .given upto 34 wks. Its role is still controvercial.

•           Bed rest - absolute bed rest is not recommended but restricted mobility with adequate rest does help in lowering bp

•           Salt restricted diet - no role

•           Fish oil supplementation - no role

•           Antioxidents - no role

•           High dose calcium - no proven role but may be beneficial in calcium deficient women

Treatment

Management depends upon the following:

1.      Severity of disease

2.      Period of gestation

3.      Maternal condition

4.      Fetal condition

Mild Pre eclampsia General

•           Women with mild pre eclampsia <37 wks gestation are managed expectantly with close maternal and fetal monitoring.

•           Ideally all patients with newly diagnosed or persistent or worsening disease should be admitted to hospital for initial evaluation and stabilization.

•           A detailed history and examination including signs & symptoms of severe disease should be recorded.

•           Maternal weight should be checked on admission and regularly thereafter.

•           BP record 4 hourly (in Eclampsia Chart)

•           Urine for proteins twice a week

•           Weekly RFT, LFT, uric acid, platelet count & hematocrit

•           Weekly fundus examination

•           Ultrasonographic evaluation of fetal size, amniotic fluid and NST and BPP on admission and every 1-2 weeks

•           Daily fetal movement count is recorded

Drugs

•           Sedation - Sedatives and tranquilizers are not prescribed routinely

•           Diuretics - Should be avoided as they can be harmful to the fetus. May decrease the placental perfusion causing IUGR, can cause rise in blood urea, uric acid and can cause neonatal thrombocytopenia.

•           Diuretics are to be used only in Pulmonary edema, Cardiac failure and in some cases of severe generalized anasarca.

•           Anti hypertensive drugs are generally not recommended as they may lower the BP but do not decrease the complications or the perinatal mortality.

•           Corticosteroids - Antenatal corticosferoids (betamethasone) to promote fetal lung maturity should be administered to women < 34 wks gestation as they are at increased risk of progressing to severe disease and pre term delivery.

Management of labour

Mild and stable cases are generally allowed to go upto term. Indications for early delivery are:

1.   Worsening of hypertension, proteinuria or vital organ involvement

2.   IUGR or fetal distress

•           Generally the labor is induced at 37 -38 wks.

•           Method of induction depends on Bishop score. If cervix is favourable (Bishop score > 6) low rupture of membranes followed by oxytocin infusion is used. If cervix is unfavourable (Bishop score < 6), prostaglandin E2 gel vaginally or intracervically is used to ripen the cervix.

•           During labor strict fetal & maternal monitoring is done. Aim is to deliver vaginally.

•           LSCS is done only for obstetric indications

•           Third stage to be managed actively by 10 units oxyfocin tIM

•           Fluid balance should be monitored closely to avoid overload. Maintenance fluid of 80 ml/hour is adequate in the absence of excessive loss.

Severe pre eclompsia management -

•           Hospitalization in a tertiary hospital is required

•           Bed rest

•           Daily monitoring of vitals, DFMC, NST, weight record

•           Urine protein testing twice a week

•           Weekly ultrasound for fetal monitoring, Doppler study every 2 weeks or earlier if required

•          Look for signs and symptoms of impending eclampsia

•          Anti hypertensive treatment: May be started when systolic BP is 160 mm Hg or diastolic BP is 105 or 110 mm Hg. The diastolic BP should be kept between 90 and 100 mm Hg to prevent complications like cereBPal hemorrhage

•           Methyldopa 250 mg 8 hourly is started initially, can be increased to a maximum of 500 mg 6 hourly.Or

•           Labetalol 100-200 mg 8 hourly can be given.

•           Nifedipine 10 mg 4-6 hourly can also be given.

•           Corticosteroids - If < 34 wks gestation, Betamethsone 12 mg I/M 2 doses 24 hours apart should be given for pulmonary maturity.

Indications for delivery

1.	Worsening of maternal condition
2.	Fetal compromise
3.	Completion of 34 weeks of gestation
4. ·	Premature labor In cases of severe pre eclampsia with gestation< viability or pregnancy should be terminated.	34 weeks, the

·        Prophylactic Anti convulsant treatment using Magnesium sulphate should be given to severe pre eclampsia cases with impending eclampsia and during labor & 24 hours post partum as it reduces the development of eclampsia.

·        Urine output is monitored using Foleys catheter.

·        Fluid overload is avoided.

·        Blood, platelet concentrates and fresh frozen plasma to be given if there is coagulopathy.

·        Labor to be induced by oxytocin or prostaglandin E2 gel & amniotomy depending upon Bishop score.

·        LSCS to be done for obstetric indication. Epidural can be given if coagulation profile is normal.

·        For third stage active management 5-10 units of oxytocin can be given I/M

Post natal care

·        Patient is sent home after improvement in general condition and control of BP.

·        BP & proteinuria is checked 6 weeks post partum.

·        OCP & IUCD can be advised, postpartum ligation is avoided for fear of thromboembolism.