Pregnancy Hypertension Rafiq

Dr. Noshaba Rafiq M.B.B.S. M.C.P.S F.C.P.S E.mail

Bill Cosby

s more than hypertensi ve disorders of pregnancy. It is probably the most studied

Placenta is the central player inducing changes in the fetus and the mother. No fetus is required for the development of pregnancy induced hypertension.

Basic Management Objectives

• Termination of pregnancy with least possible trauma to the mother and the fetus • Birth of an infant who subsequently thrives • Complete restoration of health to the mother

Prophylaxis • There is no true prophylaxis • Aspirin does not work (CLASP & ECPPA) • Control of diabetes and hypertension (where present) may be helpful in most cases

Detection No single screening • Plasmareliable fibronectin Plasma fibronectin test or level level affective* • Platelet A II receptors

Platelet A II receptors Urinary calcium

• Urinary calcium *Stamilio et alFasting 2000

• Fasting insulin levels

insulin levels

Management Early detection • Look for risk factors

• Note any change in BP • Note any rapid weight change • Take symptoms of headache & epigastric discomfort seriously • Ask for tightening of rings

Hospital Management • Detailed documentation of signs & symptoms • Daily scrutiny of clinical findings such as headache, visual disturbances, epigastric discomfort • Weight checked every day • Assessment for proteinuria every 2 days • BP readings every 4 hours (except between midnight and morning) • BU, Sr. Creat, platelets, uric acid levels determined

Fetal Monitoring • Repeated antenatal examinations • Serial ultrasounds • Dopplers • TcO2 monitoring • Cordocentesis

Outpatient Management • BP of 140/90 should be monitored daily on OP basis • Weekly antenatal visits should be initiated • Development of significant proteinuria or further elevation of BP should result in hospitalization

Hospital Management • Frequent abdominal examinations • Ultrasound and CTG assessment of fetal well being • Use of antihypertensive agents • Use of anticonvulsants • Plan for delivery

Termination of Pregnancy • Delivery is the cure for gestational hypertension • When the fetus is preterm there is need to temporize in the hope that a few more weeks may be gained • With moderate or severe preeclampsia that does not improve after hospitalization delivery is usually advisable for the welfare of both mother and the fetus

Termination of Pregnancy • Try to prolong pregnancy considering safety • If a patient needs an anticonvulsant she needs to be delivered • Induction can be carried out by prostaglandins or oxytocin • No ergometrine • C section as a last resort

Deciding for the optimal time of delivery?

Do Not Gener alize

It will depend upon • Severity of disease • Duration of gestation • Condition of cervix

Antihypertensives – Methyl DOPA – Nifedipine – Labetalol – Hydralazine – Other agents

 They are used for BP readings of 160 systolic or 110 diastolic or higher  They protect the mother but have an adverse effect on the fetus

MethylDOPA • This is thought to act centrally and is now considered a sympathomimetic instead of sympathoplegic • It has the longest track record of safety • It however possesses side effects of failure to control BP, lassitude, depression and immune mediated haematological changes • The oral dose varies between 750 mg to 4 gms daily Intravenously 250-500 mg is used 6 hourly • It has a lag period of few hours before it starts to work

Nifedipine • It is a calcium channel blocker • This has rapid onset of action orally and sublingually (10-15 min) • It may cause tachycardia and precipitous fall in BP and headaches • It is given 4-6 hourly • Slow release preparations are given twice daily • The tocolytic effect is only theoretical

Labetalol • This is an alpha and beta adrenergic blocker • It can be given orally (100 mg twice daily increased upto 400 mg twice daily) and intravenously (20 mg / hour doubled every 30 minutes) • It results in gradual fall in BP and has predictable action

Hydralazine • It is an arterial dilator • It is given orally (25 mg twice daily to 50 mg twice daily), intravenously (50-150 micro grams/min) • It has a lag period of 20-30 min • It can cause severe headaches, and may fail due to tachyphylaxis • A lupus like syndrome is quite rarely seen

GTN • Causes veno dilatation but some effect on arteries as well • Results in significant lowering of systolic and diastolic BP • Can be used as an alternative agent to well known drugs* • Not however recommended for common use

*Cetin et al 2004

Other Agents • Newer agents like amylodipine and nimodipine have also been tried but are just expensive variants of nifedipine • ACE inhibitors are contraindicated • Diazoxide and minoxidil are not used in Obstetrics • Nitroprusside is toxic to the fetus and contraindicated

Management of Eclampsia • Control of convulsions • Correction of hypoxia & acidosis • Control of BP • Delivery

Anticonvulsants – Magnesium sulphate – Diazepam – Phenytoin – Other agents

Magnesium Sulphate • It probably works by neuronal calcium blocking through the glutamate channel • It will nearly always arrest convulsions • It does not depress the maternal sensorium • The fetus is least affected • It is currently the anticonvulsant of choice in eclampsia

Magnesium Sulphate Protocol • 4 gms IV as 20% soln @ 1 gm/min • 10 gms of 50% soln. 5 gms in each buttock • If convulsions persist after 15 min give 2 gms IV again as 20 % soln • Every 4 hours 5 gms of 50% soln given in alternate buttock • Discontinued 24 hours after delivery

Magnesium Sulphate Protocol • If Mg levels are monitored it muse be between 4 -7 mEq/L – If clinical monitoring only The patellar reflex must be present Respiration not depressed Urine output > 100 mL in the last 4 hours

Diazepam • It is a very good agent to terminate a fit (10 mg IV repeated if necessary) • It is not a good agent to prevent a fit • If depresses maternal CNS • It makes CTG unreliable as a fetal monitor • Doses more than 40 mg must not be used in 24 hours • It accumulates in the fetus and results in problems after birth

Phenytoin • It is little used in obstetrics • It is a difficult drug to administer • If has shown no advantage over magnesium sulphate • ECG monitoring is mandatory with its use

Other Agents • Rarely thiopentone sodium or tribromoethanol are used as adjuvants to magnesium sulphate • It is not mandatory to sedate the patient so sedatives are not usually recommended • Phenobarbitone and chlordiazepoxide have also been used in the past but are not advocated now • Clonazepam can be used instead of diazepam to terminate a fit

Maternal complications • Central nervous system  Eclamptic convulsions  Cerebral haemorrhage  Cerebral oedema  Cortical blindness  Retinal detachment

• Renal  Cortical necrosis  Tubular necrosis

• Liver  Jaundice  HELLP

Hepatic rupture • Coagulation  DIC  Microangiopathic haemolysis  HELLP

Postpartum Care • After delivery there is usually rapid improvement but eclampsia can appear for the first time or persist postpartum • The women is discharged if severe HTN has abated or no fit has occurred for 48 hours

Future Counseling • There is a higher risk of PIH recurring in subsequent pregnancy • There is also a higher risk of developing chronic hypertension