HYPERTENSIVE

DISORDERS IN PREGANCY

OBJECTIVES

At the end of this session you should be able to:

1. Outline diagnostic features of pre-eclampsia

2. Classify pre-eclampsia according to severity

3. Outline risk factors for pre-eclampsia

4. Outline maternal and fetal complications of pre-

eclampsia.

5. Describe the management of pre-eclampsia and

eclampsia.

I. INTRODUCTION

Synonyms:

Toxemia of pregnancy, pre-eclampsia, EPH gestosis, pregnancy induced hypertension.

Pre-eclampsia commonly manifests after the 20th week of pregnancy.

Prevalence of pre-eclampsia: varies from one place to another Severe pre-eclampsia and eclampsia

Are serious and potentially fatal Third commonest cause of maternal mortality

Occurs prior to, during or after delivery

II. DIAGNOSIS OF PRE-ECLAMPSIA

When SBP > 140 mm Hg, DBP > 90 mm Hg

in a woman known to be normotensive prior

to pregnancy.

The diagnosis requires 2 such abnormal BP

measurements recorded at least 6 hours apart.

III. RISK FACTORS

Young maternal age Nulliparity: 85% of pre-eclampsia occur in

primigravida. Increased placental tissue for gestational age:

Hydatiform moles, twin pregnancies Family history of pre -eclampsia Diabetes mellitus Renal diseases, Chromosomal abnormality in the fetus (eg, trisomy).

RISK FACTORS cont

Worrisome signs for pre-eclapmsia development

Rapid increase of weight during the latter ½ of

pregnancy

An upward trend in diastolic BP even while still

within normal range

IV. CLASSIFICATION OF PRE

ECLAMPSIA:

ACCORDING TO SEVERITY

1. Mild pre-eclampsia2. Moderate pre-eclampsia3. Severe pre-eclampsia

1. Mild to Moderate Pre eclampsia Diagnostic Features

Systolic BP is 140 -160 mmHg Diastolic BP is 90 – 100 mmHg Proteinuria up to ++

2. Severe pre-eclampsia

Also called – Imminent eclampsiaSymptoms Severe & persistent occipital or frontal headaches Visual disturbance: blurred vision, photophobia Epigastric and/or right upper-quadrant pain Signs Diastolic BP > 11ommHg, systolic BP > 160mmHg Proteinuria +++ or more Altered mental status Hyper-reflexia Oliguria

HELLP SYNDROME

Is a severe form of pre-eclampsia

Affects approx 10% of women with severe preeclampsia and 30-50% of women with eclampsia.

Characterized by:

Hemolysis,

Elevated liver enzymes

Low platelet count.

Increased mortality rate and DIC

V. PATHOPHYSIOLOGY

There are several theories and etiologic mechanisms.

Vasospasm theory: Most favored theory

Vasospasms → vasoconstriction → resistance →

arterial BP

Eclampsia:

Cerebral arterial vasospasm → cerebral edema or

infarction and/or cerebral hemorrhage

VI. COMPLICATIONS OF SEVERE PRE-ECLAMPSIA AND ECLAMPSIA

Maternal complications

CVS Haemoconcentration (cause: vasoconstriction and vascular

permeability) Hamatological changes – HELLP → DIC

Kidneys Decr RBF→ ↓GFR → RTN and RCN→ acute RF Proteinuria – due to permeability to large protein,⇈ Oliguria – both renal perfusion and GFR decrease.

COMPLICATIONS OF SEVERE PRE ECLAMPSIA AND ECLAMPSIA cont

Brain Cerebral edema Infarction, cerebral hemorrhage Blindness: Due to -?retinal artery vasospasms and

retinal detachment Fever 39ºC: a grave sign, may be a consequence of

intracranial hemorrhage. Coma – may be a result of CVA

COMPLICATIONS OF SEVERE PRE ECLAMPSIA AND ECLAMPSIA cont

RS : Pulmonary oedema and cyanosis

Utero-placental perfusion Vasospasms → decr perfusion → distress and

death Histological changes in the placental bed: acute

artherosis – lipid rich cells of the uteroplacental arteries

Fetal complications IUFD, IUGR

MAJOR CAUSES OF MATERNAL DEATH

Cerebrovascular accident (CVA)

Pulmonary oedema

Cardiac failure,

Renal failure

VII. WORK UP - INVESTIGATIONS

Urine analysis Proteinuria

A 24-hour urine collection Quantity of urine and protein

Uric acid level: GFR and creatinine clearance decrease →in ↑uric acid

levels. LFT – Transaminases USS – fetal wellbeing, if the GA is < 20/40 R/O

moles.

VIII. MANAGEMENT OF PRE ECLAMPSIA

1. MILD - MOD PRE ECLAMPSIA

A: Dispensary & Health centre

Antihypertensives

Aldomet 250 mg 8 hourly for 7 days,

Bed rest at home

REFER within one week to Hospital for further

management

MANAGEMENT OF PRE ECLAMPSIA

1. MILD - MOD PRE ECLAMPSIA cont

B. Hospital

Antihypertensives: Aldomet,

Bed rest at home,

Sequential work ups,

Fetal movements monitoring,

Schedule antenatal clinic every 2 weeks up to 32 wks and

weekly thereafter

MANAGEMENT OF PRE ECLAMPSIA

1. MILD - MOD PRE ECLAMPSIA cont

B. Hospital Strongly advice the woman to deliver in a hospital Plan delivery at 38/40 Advice the mother to come to the health facility in case of

severe headache, blurred vision, nausea or upper abdominal pain.

Manage as severe pre-eclampsia: If not responding to treatment i.e. if the systolic BP is > 160 mmHg, or the diastolic BP is > 100mmHg or there is proteinuria +++

MANAGEMENT OF SEVERE PRE ECLAMPSIA AND ECLAMPSIA

Note: Severe pre-eclampsia is managed like eclampsia

Management protocol for eclampsia Keep airway clear Control convulsions Control BP Control fluid balance Antibiotics Investigations Deliver the mother

MANAGEMENT CONT

BP CONTROL

Keep SBP between 140 -160 mm Hg and DBP between 90 -

110 mm Hg

?Why these levels: Avoid potential reduction in either

uteroplacental blood flow or cerebral perfusion pressure.

Drugs:

Anti HPTs: Hydralazine, nifedipine, or labetalol

Diuretics are not used except in the presence of pulmonary

edema

MANAGEMENT: CONTROL CONVULSIONS

I. An overview on MgSO4. Mechanism:

Cerebral vasodilator → reducing cerebral vasospasm → ↓ischemia (brain).

Superior to other anti-convulsants used to control and prevent fits; Important part of mgt of eclampsia Recurrence rate after MgSO4 = 10 -15%

Improves maternal and fetal outcome

CONTROL CONVULSIONS - REGIMEN

1. INTRAMUSCULAR REGIMEN

i. Loading dose

Give MgSO4 4 g (i.e. 20mls of 20% solution) +

200mls NS or sterile water I.V over 5 minutes

Follow promptly with 10g (i.e. 20ml of 50%

solution), 5g in each buttock as deep I.M with

1ml of 2% lignocaine in the same syringe

MANAGEMENT CONT

CONTROL CONVULSIONS - REGIMEN

1. INTRAMUSCULAR REGIMEN cont

ii. Maintenance dose

MgSO4 5 g (i.e. 10ml of 50% solution) + 1 ml

lignocaine 2% 4 hourly in alternate buttocks.

NOTE:

IM inj. are painful and are complicated by local

abscess formation in 0.5% of cases.

The intravenous (IV) route is therefore preferred

MANAGEMENT CONT

CONTROL CONVULSIONS - REGIMEN

2. INTRAVENOUS REGIMEN

i. Loading dose

MgSO4 4 g (i.e. 20mls of 20% solution) + 200mls

NS I.V over 5 minutes

ii. Maintenance dose

MgSO4 4 g (i.e. 20ml of 20% solution) IN 500ml NS

4 hourly for 24 hrs after the last fits

MANAGEMENT CONT

CONTROL CONVULSIONS - REGIMEN

Recurrent fits (any regimen):

Therapeutic dose may not have been reached

Give 2g (i.e. 10ml of 20% solution) i.v. over 5

minutes

Treatment duration:

Continue for 24 hours after delivery or last

convulsion, whichever occurs first

MANAGEMENT CONT

Magnesium toxicity

Causes loss of deep tendon reflexes, followed by respiratory depression and ultimately respiratoryarrest.Thus, before repeating MgSO4, ensure that; RR ≥ 16/min Patellar reflexes are present Urinary output is at least 30ml per hour over 4 hours Otherwise withhold or delay MgSO4 Keep antidote ready In case of respiratory arrest: Assist ventilation and administer

calcium gluconate

MANAGEMENT CONT

DELIVER THE MOTHER

Delivery should be within 6-8 hours of onset of fits

Vaginal delivery is the safest mode of delivery Assessment

R/O contraindications to SVD Bishop score

If the cervix is favourable - induce labour Otherwise prepare for C/S

MANAGEMENT CONT

Management of labour

1st stage

Relieve pain: pethidine 25 mg iv every 2-4 hours

Augmentation of labour

Monitor FHR,

2nd stage: Assist with vacuum extraction

3rd stage: Active management

Oxytocin 10 IU i.m after delivery of anterior shoulder

Cord traction

Squeezing clots after delivery of the placenta

MANAGEMENT CONT

Management of labour

If there is delay perform C/S

Post delivery: Continue observation for at least 48 hrs post

delivery Record and monitor BP and urine output for at

least 48 hours after delivery, Keep the pt in hospital until BP stabilizes, Continue with aldomet PO until BP back to

normal