Diabetes in Pregnancy

Dr Hennie Lombaard

Physiological changes

• Fasting glucose levels decreased• Serum levels increased after a meal.• Doubling of insulin production • Anti–insulin hormones:

– Human placental lactogen– Glucagon– Cortisol

Physiological changes

• Renal tubular threshold decrease

• In normal pregnancy starvation leads to a breakdown of triglyceride, this leads to liberation of fatty acids and ketone bodies.

Classification in pregnancy

Diabetes in pregnancy

Pre-existing DM

IDDM NIDDM

Gestational DM

Pre-existing DM True GDM

Diagnosis of Diabetes Mellitus

• Random glucose: > 11,1mmol/l• Fasting plasma glucose > 7,0mmol/l• HbA1C >6.5

Diagnosis of GDM

• Fasting plasma glucose >5.1

• OGTT 1 hour value:– >10

• OGTT 2 hour value:– >8.5

Effect of pregnancy on pre-existing DM

• Increase need of Insulin• Deterioration of nephropathy• 2fold increased risk of deterioration in

retinopathy• Hypoglycaemia more common• Women with autonomic neuropathy

experience deterioration of their symptoms.

Effect of DM on pregnancy:

• Increased risk of miscarriage• Increased risk of pre-eclampsia (1% increase in

HbA1C cause a 60% increase in risk of PET)

• DM nephropathy associated with normochromic normocytic anemia, severe oedema and proteinuria.

• Increased c/section rate• Increased risk of infection.

Fetal complications of DM

• Congenital abnormalities: HBA1c < 8% risk is 5% and HBA1c > 10% risk is 25%

• Increased neonatal mortality• Increased perinatal mortality• Macrosomia• Late stillbirth• Premature delivery• Neonatal hypoglycaemia• Polycytheamia• Jaundice

Management:

• Maternal near normal normoglycemia• Increased home glucose monitoring• Target values:

– < 5,0 – 5,5mmol/l capillary fasting– < 7,0 – 7,5mmol/l post preandial.

• Strict adherence to low-sugar, low-fat, high-fibre diet is important. Patients require 3 snacks.

Management:

• Basal bolus regimen with short acting before meals and intermediate acting insulin at bedtime.

• Opthalmological examination• FBC, UCE, 24 hr urine protein creatinine

clearance and ECG.• Strict hypertension control.

Obstetric Management:

• Early dating scan• 11 - 14 weeks nuchal translucency scan• 20 – 22 weeks detail anatomy scan• Regular growth scans in the 3rd trimester• Pregnancies not allowed to continue past

40 weeks

Obstetric management:

• The Academic Complex protocol:– If not macrosomic and good control:

• Deliver at 38 weeks and if not confirm at 38 weeks with a positive PG

– If a macrosomic fetus or poor control do PG from 35 weeks and deliver if mature

Intrapartum management:

• IV dextrose infusion 500ml/8hr with short acting insulin and aim for capillary glucose of 5-8mmol/l

• Do hourly sliding scale.• Give potassium replacement or check

potassium regularly.• After delivery of the placenta half the

insulin infusion.

Contra indications for pregnancy:

• Ischaemic heart disease• Untreated proliferative retinopathy• Severe gastroparesis• Severe renal impairment

Gestational diabetes mellitus:

• Definition: National Diabetes Data Group (1985)– Carbohydrate intolerance of variable severity

with onset or first recognition during the present pregnancy.

Clinical features:

• Asymptomatic and develop in the 2nd or 3rd trimester

• More commonly diagnosed in women:– A family history of DM– Previous large-for-gestational-age infants– Obesity– Advanced maternal age – Certain ethnic groups

Importance of GDM:

• Women dx with GDM at increased risk for type 2 DM

• Some women have pre-existing DM• GDM is associated with adverse

pregnancy outcome

Screening:Clinical risk factors:

• Previous GDM• Family history of DM• Previous macrosomic baby• Previous unexplained stillbirths

• Obesity• Glycosuria• Polyhydramnios• Large-for-gestational-age infants• Certain ethnic groups.

Management:

• Diet advice the same as for DM• Obese women get a calorie reduced diet• Home glucose monitoring• Persistent hyperglycaemia an indication to

start insulin. Fasting > 5,5mmol/l or post prandial > 7,5 -8,0mmol/l

• Metformin can be used in pregnancy• Glibenclamide does not cross the placenta

and may be an alternative

Intrapartum management:

• Women on oral or low insulin do not need continuous insulin therapy.

• Women on large insulin needs continuous insulin therapy.

• Women with GDM require a formal OGTT 6 weeks after delivery

Hypertension in Pregnancy

Physiological changes

• Decrease in BP in 1st trimester until the 22nd to 24th week of pregnancy

• BP drops immediately post partum

Risk factors

• General– Age– Obesity

• Genetic – If their mother had PET risk is 25%– If a woman’s sister had PET her risk is 35-

40%

• Obstertirc factors– Primiparity (2-3 fold risk)– Multiple pregnancy (2 fold)– Previous PET (7 fold)– Long birth interval (2-3 fold if 10 years)– Hydrops– Hydatiforme mole– Triploidy

• Medical factors– Pre-existing hypertension– Renal disease– Diabetes– Antiphosfolipid antibodies– Connective tissue disorders– Inherited thrombophilia

Diagnosis:

• Systolic BP > 140mmHg or a diastolic BP > 90 mmHg on more than 2 occasions at least 6 hours apart

• A BP of more than 160/110 mmHg • For gestational or pre-eclampsia it is with

onset after 20 weeks.

Diagnosis PET

• Hypertension with onset of 1 of the following:– Renal impairment– Liver impairment– Haematological impairment– Neurological impairment– Growth restriction

Management:

4gr Magnesium sulphate in 200ml saline over 20min ivi5gr Magnesium sulphate with 1ml Lignocaine imi in each buttock.

STABILIZATION:

Admit High Care Obstetrics UnitIntra venous line: Ringer lactate 100ml bolus ivi over 20 min (The normal 300ml bolus is made up out of 100ml Ringers lactate and 200ml Saline)

Magnesium Sulphate

FLUID MANAGEMENT

Maintenance: 5 gr four hourlyCheck before next dosage:Urine output > 30ml/hrTendon reflexes presentRespiratory rate more than 16/min

If signs of over dose If any is absentDelay second doses with another 4 hours or only give half t If signs of over dose he dose.

Give calcium gluconate

FLUID MANAGEMENTUrinary Catheter

Fluid management:Give Ringers lactate 125ml/hr ivi.Start a fluid balance chart.

Urine output less than 30ml/hrGive Ringers lactate bolus 200ml.

Urine output less than 30ml/hrCheck her fluid balance

If she is in a + fluid balanceLow dose Dopamine infusion

Nifedipine Dosage:10mg orally p.o. if BP > 160/110mmHgContra indications:Pulse > 120 beats/minCardiac lesionUnable to swallow.

BLOOD PRESSURE CONTROLLRepeat blood pressure after 20min and if diastolic >110 or systolic > 160

Check BP after 20 min

Labetolol:Dosage:Start with 20mg, 40mg, 80mg, 80mg, and 80mg until a maximum of 300mg.Give bolus every 10min until BP less than 160/110 mmHgContra indications:Patients with asthmaPatients with ischaemic heart disease

NEUROLOGICAL STATUS:If patient is still confused

Check saturation and Blood pressure

If normal:Give Haloperidol

If abnormal Correct abnormality

The patient should now have been stabilized. A full clinical evaluation needs to be done.

EVALUATION: Mother

• CNS• Resp. System• CVS• Liver• Renal• Hematological• Immune system• Musculosceletal

• Systemic clinical exam that include.– High care observations.– GCS, RR, BP, pulse, Sats,

fluid balance chart.

• Biochemical eval.– Hematocrit, platelets.– Creatinine, AST.– 24 hour protein clearance.

EVALUATION: Fetus

• Sonar.– Estimated fetal weight.– Structural abnormalities.– Amniotic fluid index.– Doppler umbilical art.– Trans cerebellar diameter.– Middle cerebral artery

Doppler.– Ductus Venousus

waveform.

• CTG– If regarded as

viable– 6 hourly

Indications for delivery:Foetal distressIntra uterine deathExpected weight more than 2kg or sure gestation more than 34 weeks.Any signs of maternal organ invovement Platelets < 100 AST > 80 Creatinine > 100Uncontrollable hypertensionEclampsiaProven lung maturityFoetal abnormality

Expectant management:Only if mother and foetus stable and no indication for delivery:Keep in High care/High risk until hand over round.Transfer to Silver white firm6 hourly CTGDaily full clinical evaluationTwice weekly biochemical and haematological evaluation.

Place on Disprin half tablet dailyPlace on Calcium daily

Once the mother is stable and the foetus is stable decide on further management.

Better in Better out.

Drugs:

• Methyldopa– Depression– Liver function test abnormalities– Haemolytic anaemia

• Calcium channel blockers– Headache– Facial flushing

• Labetolol

Prophylaxis:

• Low-dose aspirin:– Hypertension and renal disease– Hypertension and diabetes– Women at risk of PET– Women who had PET– Antiphospholipid syndrome

• Calcium– If calcium depleted diet 2gr/day

Prophylaxis:

• Folic acid– 5mg/day especially if hyperhomocysteinaemia

Conclusion:

• PET is a dangerous disease and aggressive management is needed.

• Patients should be in a high care firm for the expectant management.