Hypertensive disorders in

pregnancy

ANUM FATIMA

08-226

Batch E

Hypertensive disorders are the

most common and yet serious

conditions seen in obstetrics

Classification

Pre-eclampsia

Eclampsia

Preeclampsia superimposed

on chronic hypertension

Chronic hypertension

with pregnancy

Gestational hypertension

Blood Pressure ≥ 140/90mmHg on two

or more occasions

- in a previously normotensive patient

- after 20 weeks gestation

- without proteinuria

- returning to normal 12 weeks after

delivery

Almost half of these develop

preeclampsia syndrome

GESTATIONAL HYPERTENSION

GESTATIONAL HYPERTENSION

GESTATION ≥ 20 WEEKS

SUSTAINED HYPERTENSION ( ≥

140/90)

No proteinuria

DEFINITION

SYMPTOMS

EXAMINATION

GESTATIONAL HYPERTENSION

Sustained B.P

No proteinuria

NONE

Unremarkable

Preeclampsia

◦ It is defined as hypertension of at least

140/90mm Hg recorded on two separate

occasions at least 4 hours apart and in

the presence of at least 300mg protein in

a 24 hour collection of urine, arising after

the 20th week of gestation in a previously

normotensive woman and resolving

completely by the 6th postpartum week.

(

RISK FACTORS for PREECLAMPSIA

DEMOGRAPHIC

OBSTETRICS

MEDICAL

NULLIPARA

(Age extremes <20yrs ,

>35yrs )

1. Multiple gestation

2. Molar pregnancy

3. Non-immune hydrops

1. Diabetes mellitus

2. Chronic HTN

3. Renal disease

4. SLE

MILD PREECLAMPSIA

GESTATION ≥ 20 WEEKS

SUSTAINED HYPERTENSION (≥ 140/90)

Proteinuria (≥300mg /24 hr)

NONE

SYMPTOMS

EXAMINATION

PATHO -

PYSIOLOGY

MILD PREECLAMPSIA

NONE

NONE

Diffuse Vasospasm

Capillary injury

MILD PREECLAMPSIA

LABORATORY

FINDINGS

MANAGEMENT

PROTEINPROTEINURIA

URIAProteinuria (1-2+)

Hemoconcentration

< 36 wks Conservative

>36 wks MgSO4 and

Delivery

GESTATIONAL HYPERTENSION

GESTATION ≥ 20 WEEKS

SUSTAINED HYPERTENSION (≥ 140/90)

NO PROTEINURIA

MILD PREECLAMPSIA

SUSTAINED HYPERTENSION ( ≥

140/90)

Proteinuria ( ≥ 300mg /24 hr)

GESTATION ≥ 20 WEEKS

BLOOD

PRESSURE

PROTEINURIA

SYMPTOMS

CRITERIA: SEVERE PREECLEMPSIA

≥ 160/110

≥ 5grams

1. Headache

2. Epigastric pain

3. Visual changes

CRITERIA: SEVERE

PREECLEMPSIA

LABORATORY

FINDINGS

SIGNS

DIC

Elevated Liver

enzymes

1. Pulmonary edema

2. Oliguria

3. cyanosis

new onset of seizures or unexplained coma

during pregnancy in patients with pre-existing

preeclampsia and without pre-existing

neurological disorder.

ECLAMPSIA

rebra

ECLAMPSIA

SYMPTOMS

PATHO -

PYSIOLOGY

RISK FACTORS Same as Preeclampsia

Cerebral vasospasm ,

ischemia and edema

Generalized tonic-

clonic

SEIZURES

ECLAMPSIA

LABORATORY

FINDINGS

MANAGEMENT

Proteinuria

HemoconcentrationDIC

Elevated Liver

enzymes

1. Stop convulsions with MgSO4

2. Prompt delivery at any

gestational age

3. Lower diastolic B.P 90-

100mm/Hg

MANAGEMENT

IV MgSO4 – To prevent convulsions ( continue

24 hrs post-partum )

LOWER B.P ( hydralazine or labetalol)

INDUCE LABOR (IV oxytocin and amniotomy

)

Blood pressure ≥ 140/90 before 20 weeks of

gestation

OR

persistence of hypertension beyond 12 weeks

after delivery.

CHRONIC

HYPERTENSION

CHRONIC HYPERTENSION

GESTATION < 20 WEEKS OR Prepragnancy

SUSTAINED HYPERTENSION

(≥140/90)

+/- PROTEINURIA

CHRONIC HTN PREGNANCY

PROGNOSIS

GOOD

PROGNOSIS

POOR

PROGNOSIS

WORST

PROGNOSIS

B.P 140/90 to 179/109

No end organ damage

KIDNEYS: Renal disease

EYES : Retinopathy

HEART : Left Ventricular

Hypertrophy (B.P

>180/90)

Uncontrolled HTN

Chronic HTN

+Superimposed PIH

D

MANAGEMENT OF CHRONIC HYPERTENSION

If antihypertensive meds needed

- Methyl dopa is drug of choice (or labetalol)

Serial ultrasounds (increase risk of IUGR >30

weeks )

Induce labor at term

DC antihypertensive meds

(if B.P <100 mm Hg diastolic)

Serial B.P and urine protein

(watch for superimposed preeclampsia)

SUPERIMPOSED PREECLAMPSIA

(on Chronic Hypertension)

New-onset proteinuria > 300 mg/24 hrs in

hypertensive women but no proteinuria

before 20 wks gestation

A sudden increase in proteinuria or blood

pressure or platelet count < 100,000/ cu

mm in women with hypertension and

proteinuria before 20 wks gestation.

23

CHRONIC HTN SUPERIMPOSED PIH

CHRONIC HYPERTENSION

Worsening BLOOD

PRESSURE

Worsening proteinuria

MANAGEMENT of Chronic HTN and

superimposed PIH

IV MgSO4 – To prevent convulsions ( continue

24 hrs post-partum )

LOWER B.P - Diastolic 90-100 mm Hg(

hydralazine or labetalol)

INDUCE LABOR (IV oxytocin and amniotomy

)

HELLP Syndrome

HTN patients with hemolysis (H), elevated liver enzymes (EL), low platelet count (LP)

4-12% of pt. with severe preeclampsia and eclampsia develop HELLP syndrome

PATHOPHYSIOLOGY

Complex disease

Appears to be triggered by the

placenta

◦ Can occur in molar pregnancies where

fetus absent

◦ Can also occur in abdominal pregnancy

(pregnancy not in uterus)

TWO – STAGE MODEL FOR

PREECLAMPSIA

Stage 1:

reduced

placental

perfusion

Abnormal

implantation

Stage 2 :

maternal

syndrome

-hypertension

-proteinuria

-endothelial

dysfunction

NORMAL

PREGNANCY

PREECLAMPSIA

Impair/ inadequate trophoblast invasion to the spiral arteries

Spiral arteries retain their charecteristic (narrow, tortuous, high resistance)

Reduce blood supply to placenta

Result in placental hypoperfusion

As a compensation

High BP in maternal

Stage 1:

reduced

placental

perfusion

Abnormal

implantation

Stage 2 :

maternal

syndrome

-hypertension

-proteinuria

-endothelial

dysfunction

WHAT CAUSES MATERNAL

SYNDROME ?????

WHAT GETS INTO MATERNAL

CIRCULATION ???

ANTI-ANGIOGENIC

FACTORSANGIOGENIC

FACTORS

Vascular endothelial

growth (VEGF)

including placental

growth factor

Transforming growth

factor- beta (TGF-B)

Look after maternal

endothelium

Soluble endoglin (sEng)

Soluble FMS-like

tyrosine kinase-1 (sFlt-1)

Released from

diseased placenta

↓PGI2

↑TXA2

Vasoconstriction

Platelet aggregation

↑Vasopressor

response

↑uterine activity

Inflammatory mediators

Coagulation disturbance

Activated endothelial cells promote coagulation and increase vasopressor sensitivity

Widespread coagulation occur (DIC)

Fibrin deposition in kidney & placenta

HPT & placental insufficiency

Cardiovascular

• Generalized vasospasm

• Increased peripheral resistance

• Reduced central venous/

pulmonary pressure

Hematological

• Platelet activation and depletion

• Coagulopathy

• Decreased plasma volume

• Increased blood viscosity

• Proteinuria

• Decreased glomerular filtration

rate

• Decreased urate excretion

Renal

Hepatic

• Periportal necrosis

• Subscapular

hematoma

• Cerebral oedema

• Cerebral haemorrhages

Central Nervous System

Organ Specific Changes associated with

Pre-eclampsia

36

RISK FACTORS

Maternal related

History of Preeclampsia in previous

pregnancy

Advanced maternal age

Family history of Preeclampsia

History of placental abruption, IUGR,

fetal death

Obesity, BMI>35 doubles the risk

Hypertension

Diabetes

Thrombotic vascular diseases

Multiple gestation

Molar pregnancy

Smoking

Large placenta

Prolonged pregnancy

Placental hydrops

Chromosomal abnormality

Fetal/placental factors

Hemoglobin and hematocrit

platelet count : decreased, if < 1 lakh

coagulation profile

LFTs : indicated in all patients

RFTs : raised (S.urea creatinine is decreased in Normal

pregnancy)

Urine Routine : proteinuria

OBSTETRIC MANAGEMENT

1. Maternal

evaluation

2. Fetal evaluation:

Daily fetal movement count

Ultrasound

Doppler ultrasound for fetal blood flow

3. Treatment of Hypertension:

Antihypertensive drugs used in

pregnancy are

-methyldopa

-hydralazine

-labetalol

4. Seizure

Prophylaxis

• Routinely used in severe

PE

• Magnesium sulphate:

most commonly used

• Initiated with onset of

labor till 24h postpsrtum

• For caesarean, started

2hrs before the section

till 12hrs postpartum

it can be given either IV or IM.

IV has good prognosis.

Loading dose for IV is 4g. i.e. 8

ml diluted in 12ml normal saline.

This 20 ml is given in 20

minutes.

Maintenance dose is 20 g i.e.

40ml diluted in 60ml

normal saline and given at rate

of 1g/hr.

Recommended regime for MgSO4

IM is also used.

Loading dose is as IV.

Maintenance dose is 5g

every 4 hrs in alternate

buttocks for 24hrs.

Mgso4 acts on NM junction

and inhibit entry of Ca++

ions thus inhibiting

excitability of neurons.

Side effects of MgSO4

Maternal :

flushing

perspiration

headache,

muscle weakness

pulmonary oedema

Neonatal:

lethargy

hypotonia

respiratory depression

Management of MgSO4 Toxicity

Calcium gluconate is antagonist for MgSO4.

it is usually given as 10 ml of 10% Calcium

gluconate in 10 minutes

The only definitive

treatment

Preeclamptic patients

divided into 3 categories

A- Preeclampsia features

fully subside

B- partial control, but BP

maintains a steady high

level

C- persistently increasing

BP to severe level or

addition of other features

5. Delivery

Management:

A: can wait till

spontaneous onset of labor

don’t exceed Expected

Date of Delivery

B: >37wk terminate without

delay

<37wk, expectant

management at least

till 34wks

C: terminate irrespective of

POG

start seizure prophylaxis

and steroids if<34wks

Delivery in Eclampsia

Unless contraindicated: Eclamptic women should

undergo normal vaginal delivery

Indications for caesarean section -

Fetal distress

Placental abruption

Unfavourable cervix

Failed induction of labour

Recurrent seizures

Investigations

Laboratory:

◦ Urine: 24 hour urine, Proteinuria.

◦ Kidney functions: serum creatinine, urea,

creatinine clearance and uric acid.

◦ Liver functions: bilirubin, Enzymes

◦ Blood: CBC, HCt , Hemolysis and Platelet

count (Thrombocytopenia).

◦ Coagulation Profile: Bleeding and clotting

time

Complications

1. Maternal:

a. Convulsions and coma (eclampsia).

b. Cerebral haemorrhage.

c. Renal failure.

d. Heart failure.

e. Liver failure.

f. Disseminated intravascular coagulation.

g. Abruptio placentae.

h. Residual chronic hypertension in about 1/3 of cases.

i. Recurrent pre-eclampsia in next pregnancies.

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Complications

2.Foetal:

a. Intrauterine growth retardation

(IUGR).

b. Intrauterine foetal death.

c. Prematurity and its complications.

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PREVENTION

• Regular Antenatal checkup:

rapid gain in weight

rising blood pressure

edema

proteinuria/deranged liver or renal profile

• Low dose Aspirin in High risk group: ↑PGs

and↓TXA2

• Calcium supplementation: no effects

unless women are calcium deficient

• Antioxidants- Vitamin C and E

• Nutritional supplementation: zinc,

magnesium, fish oil, low salt diet

Differential Diagnosis

meningitis

encephalitis

space occupying lesion

electrolyte disturbance

vasculitis

amniotic fluid embolism

medications

organ failure

stroke

Thank you