Complications of Pregnancy 2 Flashcards
Define chronic hypertension
HTN either pre-pregnancy or at booking (<20weeks or 20 weeks)
I.e. she’s had it before the pregnancy and they’ve just noticed now
Define mild HTN
Diastolic 90-99, systolic 140-149
Define moderate HTN
Diastolic 100-109 systolic 150-159
Define severe HTN
Diastolic >110, systolic >160
Define gestational hypertension
New HTN in pregnancy developing after 20 weeks
Define pre-eclampsia
Significant new HTN + significant proteinuria
What is significant proteinuria defined as?
Automated reagent strip urine protein estimation >1+
Spot urinary protein: creatinine ratio >30mg/mmol
24h urine protein collection >300mg/day
In which group of mothers is chronic HTN more common?
Older mothers
What anti-HTN can you not use in pregnancy?
ACEi - small risk of birth defects/impaired growth
ARBs
Antiduretics (risk of dehydration
Give two e.g.s of ACEis
Rampiril, enalopril
Give two e.g.s of ARBs
Losartan, candesartan
What is involved in the management of essential HTN in pregnancy?
Lower dietary Na
Aim for BP <150/100
Best anti-HTN drugs to use: labetabolo, nifedipine, methyldopa
Monitor for super-imposed pre-eclampsia
Monitor foetal growth
Watch out for placental abruption (higher risk)
What is the proper definition for pre-eclampsia diagnosis?
Mild HT on two occasions more than 4h apart or moderate-severe HT (one reading) AND proteinuria of more than 300mgms/24h (protein urine >+1 + protein:creatnine ratio >30mgms/mmol)
What systems does PET affect?
Multi-system disorder
Affects kidneys, liver, vascular, cerebral and pulmonary systems
What is the pathophysiology of PET?
Trophoblast invasion of spinal arterioles impaired –> placental/foetal hypoperfusion
Poorly perfused placenta releases pro-inflammatory proteins –> enter mum’s circulation and cause endothelium lining mum’s BVs to become dysfunction –> vasoconstriction
Imbalance between vasodilators (prostacyclin) and vasoconstrictors (thromboxane)
Endothelial cell dysfunction also affects kidneys causing them to retain more salt
Both –> HTN
Also localised area of vasospasm in mother’s BVs which can lead to reduced BF to certain organs
Endothelial cell dysfunction leads to BVs becoming more likely --> loss of protein from urine and increased water loss from vessels into tissues --> Generalised oedema (legs, hands, face) Pulmonary oedema (cough, SoB) Cerebral oedema (headaches, confusion, seizures (eclampsia))
In PET, there is vasospasm in the mother’s BVs which may lead to reduced BF to certain organs, give e.g.s of the effects of these
Kidneys –> glomerular damage –> oliguria & proteinuria
Retina –> blurred vision, flashing flights, scotoma
Liver –> injury and swelling –> elevation of liver enzymes, stretching of capsule –> RUQ pain (cardinal sign of severe pre-eclampsia)
What happens to the spiral arteries in pregnancy?
They are converted into the uteroplacental BF
They lose their smooth muscle and dilate by 5-10x
What are risk factors for developing PET?
First pregnancy Extremes of maternal age Pre-eclampsia in previous pregnancy Pregnancy interval >10y BMI >35 FH of PET Multiple pregnancy Underlying medical disorder (chronic HTN, pre-existing renal dx, pre-existing DM, autoimmune disorders (e.g. SLE)
What are the complications of PET?
High BP –> haemorrhagic stroke/placental abruption
Renal failure
Pulmonary/cardiac failure (never fluid overload these patients!)
HELLP
Eclampsia
Impaired placental perfusion –> IUGR, foetal distress, prematurity
What is HELLP?
Endothelial injury –> formation of tiny thrombi in microvasculature which uses up lots of platelets
Clots are hazardous to RBCs –> haemolysis
HELLP = haemolysis, elevated liver enzymes, low platelets
HELLP occurs in severe PET
What is eclampsia?
Pre-eclampsia + seizures
What are signs and symptoms of severe PET?
Headache, blurring of vision, epigastric pain, pain below ribs, vomiting, sudden swelling of hands/face/legs
Severe HTN >3+ urine proteinuria
Clonus/brisk reflexes, papilloedema, epigastric tenderness
Oligouria
Convulsions (eclampsia)
What biochemical abnormalities might you get in severe PET?
Raised liver enzymes, bilirubin if HELLP present
Raised urea & creatinine, raised urate
Low platelets, Hb
Features of DIC
How do you manage severe PET?
Frequent BP & urine protein checks
Check for symptoms/hyper-reflexia, tenderness over liver
Blood investigations - FBC, LFTs, renal function tests (serum urea, creatinine, urate), coagulation tests
Foetal investigations - scan for growth, CTG
Only cure is delivery of baby and placenta - consider induction if foetal/maternal condition deteriorates
Why must you monitor the mother after birth if she had PET?
Risk of PET persist into puerperium (first 6 wks)
Most seizures occur in post-natal period
How do you treat seizures in PET?
Magnesium sulphate bolus and IV infusion
Control of BP - IV labetolol, hydralazine (>160/110)
Avoid fluid overlow (aim for 80mls/hour fluid intake)
What prophylaxis do you give for PET in subsequent pregnancies?
Low dose aspirin from 12 weeks till delivery
Woman with PET have a higher risk of developing what in later life?
HTN
What is gestational diabetes?
Carbohydrate intolerance with onset in pregnancy
Abnormal glucose tolerance reverts after delivery
Those who have gestational diabetes during a pregnancy are more at risk of developing what in later life?
Type II diabetes
What is important to remember in those with pre-existing diabetes during pregnancy (in relation to their insulin intake)?
Insulin requirements of the mother increase - due to human placental lactogen, progesterone, hCG & cortisol from the placenta
So will need larger dose
What occurs to the foetus of a diabetic mother?
Maternal glucose crosses the placenta, induces insulin production in foetus –> macrosomia (& inc. risk of birth comps like PPH, shoulder dystocia) & risk of neonatal hypoglycaemia and IRDS
What foetal congenital abnormalities/problems is the foetus at increased risk of if it is born to a diabetic mother?
Cardiac abnormalities, sacral agenesis
Miscarriage/still birth
Foetal macrosomia, polyhydramnios
What obstetric complications are more common in diabetic mothers?
Shoulder dystocia
What is shoulder dystocia?
Anterior shoulder of foetus impacts into maternal pubis symphysis during delivery
How do you manage shoulder dystocia?
McRobert’s manuovre
What palsy is really common with shoulder dystocia?
Erbs (waiters tip position due to C5/6 damage)
What does pregnancy do to the diabetic mother?
Increases risk of PET, worsening of maternal nephropathy, retinopathy, hypoglycaemia, reduced awareness of hypoglycaemia, increased infections
What should a diabetic mother do preconceptually to try and have a smooth pregnancy?
Achieve optimal glycaemic control (BG 4-7mmol/l and HbA1c <6.5% (<48mmol/mol)
Folic acid 5mg
Dietary advice
Retinal and renal assessment
What should a diabetic mother do during pregnancy to have a smooth pregnancy?
Optimise blood control (<5.3mmol/l fasting, <7.8 1h postprandial, <6.4 2h postprandial, <6mmol/l before bedtime) Continue metformin/start insulin if req Glucagon injections incase needed Watch out for DKA/infections/PET Watch foetal growth
What different precautions should be taken in the birthing process if the mother is diabetic?
Induce labour 38-40wk/earlier if maternal/foetal concerns
Consider C-section if macrosomia
Maintain BG in labour with insulin-dextrose infusion
Continuous CTG
Early feeding of baby to prevent neonatal hypoglycaemia
