Hypertension, Gestational

KEY FEATURES

ESSENTIALS OF DIAGNOSIS

• Occurs after 20 weeks of gestation or up to 6 weeks postpartum in previously normotensive women

• Usually diagnosed after a rise in blood pressure of ≥ 30/15 mm Hg to a level above 140/90 mm Hg supine in the left lateral position after resting for at least 5 minutes

• May progress to preeclampsia when complicated by proteinuria, edema, or hematologic or hepatic abnormalities

• May progress to cerebral symptoms, leading to convulsions

GENERAL CONSIDERATIONS

• Hypertensive disorders of pregnancy can be divided into 4 groups:

  • – Chronic persistent hypertension, which occurs before pregnancy or before 20 weeks of gestation and persists

  • – Gestational hypertension, which develops after 20 weeks and is not associated with preeclampsia or eclampsia

  • – Preeclampsia or eclampsia: gestational hypertension with 1 or more of the following: proteinuria, renal insufficiency, liver involvement, neurologic (including seizure) or hematologic complication, uteroplacental dysfunction, or fetal growth restriction

  • – White coat hypertension

• Is a leading cause of maternal mortality

• Is an endothelial disorder that results in placental ischemia

• Occurs more frequently in women with hypertension predating pregnancy

• Occurs more frequently in primigravidas, those > 45 years old, and diabetics

CLINICAL PRESENTATION

SYMPTOMS AND SIGNS

• Nonspecific symptoms are common, such as headache, nausea, and visual disturbances

PHYSICAL EXAM FINDINGS

• Increased blood pressure

• Edema

• Hyperreflexia and clonus can occur

DIFFERENTIAL DIAGNOSIS

• Chronic hypertension

• Unclassified hypertension when blood pressure status before conception and during first trimester is unknown

DIAGNOSTIC EVALUATION

LABORATORY TESTS

• Urinalysis: to check for protein

• CBC, platelets (often low)

• Uric acid: may be elevated

• Serum albumin: may be low

• Liver function tests: may be abnormal

ELECTROCARDIOGRAPHY

• No specific abnormalities

IMAGING STUDIES

• Fetal ultrasound: may show reduced size for gestational age

• Umbilical Doppler: may show flow abnormalities

TREATMENT

CARDIOLOGY REFERRAL

• Cardiac complications of hypertension

HOSPITALIZATION CRITERIA

• Almost all with severe preeclampsia

• Complications of hypertension such as heart failure

MEDICATIONS

• Methyldopa is the primary treatment 250–1500 mg PO bid

• Nifedipine (10–20 mg PO tid) and labetalol (100–400 mg PO bid) may be used in succession for severe hypertension

• Hydralazine 10-mg boluses IV can be used every 20 minutes for acute elevations in blood pressure or IV labetalol 40–80 mg every 10 minutes prn to 300-mg maximum total dose

• Angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and atenolol are contraindicated

• For intrapartum management, IV magnesium prevents progression of preeclampsia to seizures

THERAPEUTIC PROCEDURES

• Termination of pregnancy when fetal or maternal crisis develops