Gestational hypertension resident survival guide

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Samah Obiah, MD[2], Rinky Agnes Botleroo, M.B.B.S.

Synonyms and keywords: Pregnancy-induced hypertension; PIH; Gestational hypertension;

Overview

Gestational hypertension or Pregnancy-induced hypertension (PIH) , is defined as systolic blood pressure (SBP) >140 mmHg and diastolic blood pressure (DBP) >90 mmHg on at least two occasions at least 6 hours apart after the 20th week of gestation in women known to be normotensive before pregnancy and before 20 weeks’ gestation. The BP recordings used to establish the diagnosis should be no more than 7 days apart. Gestational hypertension is considered severe if there is sustained elevations in systolic BP to at least 160 mm Hg and/or in diastolic BP to at least 110 mm Hg for at least 6 hours. It is classified as mild , moderate , and severe . The WHO classified it is one of the main causes of maternal, fetal, and neonatal mortality and morbidity.gestational hypertension is one of the most common medical disorders affecting pregnancy. The most serious maternal complications of gestational hypertension include intracerebral hemorrhage, eclampsia, and renal failure, as well as hemolysis, elevated liver enzymes, and low platelets (HELLP) syndrome and posterior reversible encephalopathy syndrome (PRES).Treatment of gestational hypertension depends on blood pressure levels, gestational age, presence of symptoms and associated risk factors.

Causes

The cause of gestational hypertension is unknown. If untreated will be life-threatening, severe gestational hypertension may cause dangerous seizures (eclampsia) and even death in the mother and fetus. Because of these risks, it may be necessary for the baby to be delivered early, before the full term of pregnancy. Some conditions may increase the risk of developing the condition, including the following:

• History of hypertension
• Kidney disease
• Diabetes
• Hypertension with a previous pregnancy
• Mother's age younger than 20 or older than 40
• Multiple fetuses (twins, triplets)
• African-American race

Common Causes

Pathogenesis theories developed about the passable causes:-

• Insufficient blood flow to the uterus or abnormal placental implantation
• Damage to the blood vessels
• A problem with the immune system
• Certain genes
• Platelet activation
• Hyperlipidaemia and insulin resistance

Diagnosis

Shown below is an algorithm summarizing the diagnosis of [[disease name]] according the the [...] guidelines.

Pregnant woman previously normotensive BP ≥140/90 mmHg >20 weeks' gestation absence of symptoms that suggest preeclampsia nulligravidity black or Hispanic ethnicity obesity mother small for gestational age

Treatment

Management of gestational hypertension remains controversial, as does the classification of its severity. Delaying the interruption of pregnancy may lead to the progression of pre-eclampsia, eventually resulting in placental insufficiency and maternal organ dysfunction, with increased risk of maternal and perinatal mortality. Aims of management are minimizing further pregnancy-related complications, avoiding unnecessary prematurity, and maximizing maternal and infant survival.

Shown below is an algorithm summarizing the treatment of gestational hypertension

Woman comes with gestational hypertension

Non- pharmacological treatment

Pharmacological treatment

❑ 30 minutes of moderate exercise on most days of the week to stimulate placental angiogenesis and improve maternal endothelial dysfunction. ❑ Strict bed rest should be avoided and encouraged to maintain normal physical activity levels, as prolonged bed rest can increase the risk for venous thromboembolism, especially given the physiological hypercoagulability of pregnancy.

❑ Methyl-dopa: a centrally acting alpha-2 adrenergic agonist, used as a first line agent mainly because of its longstanding history of safety and use in pregnancy. Blood pressure control is gradual over 6-8 hours because of the indirect mechanism of action and is best for treatment of mild hypertension rather than moderate or severe hypertension. ❑ Labetalol: a nonselective beta-blocker. Should not be given in patients withasthma as it can cause bronchospasm. It is used widely in pregnancy and has proven effective in the treatment of mild to moderate hypertension, though some data shows a slight increase in small for gestational age (SGA) infants. ❑ Procardia: a calcium channel blocker, often used in pregnancy to treat mild to moderate hypertension. It has shown indication of adverse perinatal outcomes or decreased uterine blood flow. ❑ Diuretics: can be used as second line medication. It has some usefulness in pregnancy, specifically with salt-sensitive hypertension and for patients with reduced renal function. It should be carefully prescribed to avoid hypokalemia and fetal growth restriction from intravascular volume depletion. ❑ Low dose aspirin of 81 mg or less to be initiated before 20 weeks of gestation to prevent preeclampsia as a sequelae of hypertension.

Do's

• The content in this section is in bullet points.

Don'ts

• Strength training and pure isometric exercise, such as lifting weights and aerobic exercise should be discouraged as it can acutely elevate blood pressure to severe levels. It can also increase the risk for adverse events such as stroke.
• There is no evidence that suggest benefits in restricting sodium intake during pregnancy, thus it is not recommended to limit the intake in the prevention of preeclampsia.

References

Template:WikiDoc Sources