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 preeclampsia.
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.
2.
3.
1.
Mild pre-eclampsia
Moderate pre-eclampsia
Severe pre-eclampsia
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 eclampsia
Symptoms
 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 PREECLAMPSIA 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


A 24-hour urine collection



Quantity of urine and protein
Uric acid level:


Proteinuria
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 respiratory
arrest.
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