Hypertensive disorders of pregnancy II

Part I : Complications of Severe Pre-eclampsia

Part II : Chronic Hypertension in Pregnancy

Dr.Nadia Mudher Al-Hilli FICOG

Department of Obs&Gyn College of Medicine

University of babylon

Objectives of this lecture

• Learn the complicatios that might develop in a patient with severe PE & how to deal with them

• How to deal with a patient with eclamptic fit

• Understand the risk & complications of chronic HT in pregnancy

• Managing chronic HT in pregnancy

Complications of Preeclampsia

Complication of severe pre-eclampsia are:

• Eclampsia

• HELLP syndrome

• DIC

• Adult Respiratory Distress Syndrome (ARDS)

• Pulmonary oedema

• Acute renal failure

• Placental abruption

• Intrauterine growth restriction (IUGR)

• Intrauterine fetal death

Eclampsia: • defined as new-onset tonic-clonic seizure in

an otherwise healthy woman with hypertensive disorder of pregnancy

• 44% occur postnatally, 38% antepartum & 18% intrapartum.

• The pathophysiology

•is associated with high maternal and neonatal

morbidity and mortality.

Management: • General measures:

• Do not leave the patient alone

• Call for help

• Inform consultant

• Prevent maternal injury during convulsion

–Air way:

–Breathing:

–Circulation:

–Secure intravenous access

–Urinary catheter to assess urinary out put

–Fluid input/output chart & monitoring of BP every 15-30 min and other vital signs

anticonvulsant therapy • Magnesium sulphate: membrane stabilizer &

vasodilator & reduces intracerebral ischaemia

• Loading dose 4gm bolus iv over 15-20 min followed by continuous infusion of 1gm/hr for 24 hrs fron last fit or from delivery

signs of magnesium toxicity • loss of deep tendon reflexes

• respiratory depression

• cardiac standstill.

• So, the patient should be monitored hourly by patellar reflex, respiratory rate & oxygen saturation. & urine output

Mg sulphate indications in severe PE

• Consider the need for magnesium sulfate treatment, if 1 or more of the following features of severe pre-eclampsia is present :

• ongoing or recurring severe headaches • visual scotomata • nausea or vomiting • epigastric pain • oliguria and severe hypertension • progressive deterioration in laboratory blood tests

(such as rising creatinine or liver transaminases, or falling platelet count).

• Blood pressure should be controlled using intravenous hydralazin or labetolol

• limit maintenance fluids to 80 ml/hour unless there are other ongoing fluid losses (for example, haemorrhage)

• Delivery : Choose mode of birth according to the clinical circumstances and the woman's preference.

• Postpartum care : should be in critical care setting

• Transfusion of red cells, platelets, fresh frozen plasma and cryoprecipitate or fibrinogen concentrate are required as indicated clinically and by blood and coagulation tests.

• HELLP Syndrome: the association of haemolysis (H) elevated liver enzymes (EL) & low platelet count ( LP)

• DIC with low fibrinogen may coexist.

• Definitive treatment of severe pre-eclampsia and HELLP requires delivery of the fetus

• Give antenatal corticosteroid for fetal lung maturation.

Chronic Hypertension: • Effect 2-4 % of pregnant women. Over 90% of cases

are due to essential hypertension

• causes of chronic hypertension ( secondary) include:

• Chronic renal disease

• Renal artery stenosis

• Coarctation of the aorta

• Collagen vascular disease

• Pheochromocytoma

• Cushing's syndrome

• Conn's syndrome (primary hyperaldosteronism)

High-risk characteristics in women with CHT include:

• Maternal age >40 years

• Duration of hypertension > 15 years

• BP ≥160/110 mmHg

• Diabetes

• Renal disease

• Cardiomyopathy

• Connective tissue disease

• Coarctation of the aorta

• Previous pregnancy with perinatal loss

Preconception assessment & councelling:

• life style modification • anti-hypertensive therapy: • Physical examination • Investigations: renal function test, urinalysis, 24 h urine collection for protein excretion creatinine clearance CXR ECG echocardiography

Complications of CHT in pregnancy: • Superimposed PE

• Abruptio placentae

Antihypertensive therapy: reduces the risk of severe hypertension but does not reduce the risk of superimposed PE, preterm delivery or perinatal death

• diuretics decrease blood volume & cause undesirable physiological effect, congenital anomalies & neonatal complications.

• beta-blockers cause IUGR

• ACE inhibitors & angiotensin receptor blockers cause renal toxicity & increased risk of congenital abnormalities in the fetus & should be changed

Treatment of chronic hypertension Offer pregnant women with chronic

hypertension advice on:

• weight management

• exercise

• healthy eating

• lowering the amount of salt in their diet.

Continue with existing antihypertensive treatment if safe in pregnancy, or switch to an alternative treatment, unless:

• sustained systolic blood pressure is less than 110 mmHg or

• sustained diastolic blood pressure is less than 70 mmHg or

• the woman has symptomatic hypotension.

• Offer antihypertensive treatment to pregnant women who have chronic hypertension and who are not already on treatment if they have:

• sustained systolic blood pressure of 140 mmHg or higher or

• sustained diastolic blood pressure of 90 mmHg or higher.

• When using medicines to treat hypertension in pregnancy, aim for a target blood pressure of 135/85 mmHg . (NICE Guigelines 2019) https://www.nice.org.uk/guidance/ng133/resources/hypertension-in-pregnancy-diagnosis-and-management-pdf-66141717671365

• Consider labetalol to treat chronic hypertension in pregnant women.

• Consider nifedipine for women in whom labetalol is not suitable, or methyldopa if both labetalol and nifedipine are not suitable.

• Offer pregnant women with chronic hypertension aspirin 75–150 mg once daily from 12 weeks.

• Offer placental growth factor (PlGF)-based testing to help rule out pre-eclampsia between 20 weeks and up to 35 weeks of pregnancy, if women with chronic hypertension are suspected of developing pre-eclampsia.

Fetal monitoring in chronic hypertension: • carry out an ultrasound for fetal growth and

amniotic fluid volume assessment, and umbilical artery doppler velocimetry at 28 weeks, 32 weeks and 36 weeks.

• only carry out cardiotocography if clinically indicated.

• For women with chronic hypertension whose blood pressure is lower than 160/110 mmHg deliver after 37 weeks.

• After delivery continue follow up of BP & antihypertensive therapy as needed