DISEASES IN PREGNANCY


Eclampsia

Greek for ‘like a flash of lightning’
Characterized by Convulsions and Coma.
Usually occurs in patients who have severe pre-eclampsia or imminent eclampsia or patients in whom gestational proteinuria has been superimposed on chronic hypertension.

Aetiology




30% no warning signs; 1:2000 in developed countries


Pathophysiology



Intense vasospasm;
Tissue hypoxia;
GFR further reduced;
Urinary output falls

I Disorientation stage: restless, twitches, spasmodic respiration
II Tonic stage: back arches, hands clench, grimaces, breathing ceases, becomes cyanosed, may bite own tongue.
III Clonic stage: body jerks uncontrollably, frothy saliva may fill mouth, breathing becomes stertorous.
IV Comatose (1 hour or longer) OR recurrent convulsions



Management



Magnesium sulphate (iv/im)
MgSO4 4g IV over 10-15min; then MgSO4 1g/h (as 5g in 500mL normal saline)
N.B. im less preferred as painful and 5% change of deep abscess formation

Aims of Magnesium infusion is to:
  • Control fits: relieve generalized vascular spasm; decrease sensitivity of brain to stimuli
  • Reduce BP to prevent cerebral haemorrhage
  • Deliver fetus

Magnesium works by:
  • relieve vasospasm;
  • induce cerebral vascular dilatation;
  • increase release of prostacyclin,
  • improve uterine blood flow,
  • inhibit platelet activation,
  • protect endothelial cells from injury

Monitor for Mg toxicity via testing:
  • Tendon reflexes
  • Respiratory rate (>16/min)
  • Urine output (>25mL/h) - renally excreted

Midwifery Care



Detect changes that hint second convulsion
Prevent injury during convulsion
Oxygen- provide continous oxygen
Suction to keep mouth and faces saliva free
Monitor vital sign and urinary output





Pre-eclampsia


Pathophysiology



Fetus: Later in 1st trimester, secondary invasion of maternal spiral arteries by trophoblasts is impaired, so that they remain high-resistance vessels. Placental hypoxic changes induce proliferation of cytotrophoblasts and thickening of trophoblastic basement membrane that affect metabolic function of the placenta.
Damaged endothelial cells decrease ability to secrete vasodilator substances (including nitric oxide).
Placenta: Damaged endothelial cells of the placenta, therefore secrete less vasodilator prostacyclin. Platelets secrete more thromboxane. This leads to generalized vasoconstriction and decreased aldosterone secretion.
In the woman, this causes maternal hypertension, a 50% reduction in placental perfusion, and reduced maternal plasma level.

If vasospasm persists, epithelial cell injury may occur. The trophoblast fragments are then carried to the lungs, where they are destroyed, releasing thromboplastins.
These thromboplastins cause intravascular coagulation and deposition of fibrin in the glomeruli of the kidneys (glomerular endotheliosis). This reduces GFR and indirectly increases vasoconstriction.

In advanced cases, fibrin deposits occur in vessels of the CNS, leading to convulsions.

Management



Antenatal (Prevention)
Aspirin
Calcium supplementation

Perinatal (Acute Mx)
To control BP and prevent convulsions in the mother.
To ‘buy time’ ie allow continued fetal growth in the uterus.

Mx for Pre-eclampsia
< 32 weeks: Goal is to keep fetus in utero until week 35
32- 35 weeks: Caesarean section / induce labour
35 weeks: Induce labour/ caesarean
Do not allow to exceed full term (increased risk of intra-uterine death)

Post-natal (Long-term Mx)
Antihypertensives if BP remains high after birth.
Search renal cause if severe pre-eclampsia prior 34 weeks gestation.
N.B. Proteinuria often persists for longer and is of little consequence.
1/3rd women have non-proteinuric HT in next pregnancy; but risk of recurrence of severe pre-eclampsia is les than 5%


Types of Hypertension in Pregnancy



  • Pre-eclampsia
Multi-system disorder; with
Onset of hypertension > 140/90 mmHg after 20 weeks gestation; returns to normal within 3 months of delivery.
1) Followed by Proteinuria (>300mg/24h or urine protein/creatinine ratio >30 mg/mmol)
OR
Renal insufficiency (serum/plasma creatinine >0.09 mmol/L or oliguria)
Liver disease (raised serum transaminases and/or severe epigastric/right upper quadrant pain)pre-eclampsia.jpg
Neurological problems (convulsions- elampsia; with clonus; severe headaches with hyperreflexia; persistent visual disturbances (scotomata)
Haematological disturbances (thrombocytopenia; disseminated intravascular coagulation; haemolysis)
Fetal growth restriction
  • Gestational hypertension
Hypertension that arises after 20 weeks’ gestation and resolves within 3 months of delivery, WITHOUT any of the other features of pre-eclampsia above.
  • Chronic hypertension
Essential hypertension
H/T PRIOR to conception or in the first half of pregnancy;
Without apparent underlying cause
Secondary hypertension
H/T associated with renal, re
  • Pre-eclampsia superimposed on chronic hypertension



Gestational Diabetes




2hr GTT > 7.9
If at risk, screen at 16 and 24 weeks

Illicit Substances in Pregnancy


Classification




Uppers

ecstasy
amphetamine (including ice)
cocaine (speed, ice...)

Downers (most worrisome)
Alcohol
Cannabis (marijuana, dope, weed)

Hallucinogens
LSD
Magic mushrooms
Management
Methadone (for heroine withdrawal effects)
Buprenorphine (with anti-heroine effect)