As-needed intravenous antihypertensive therapy and blood pressure control.

BACKGROUND: Hospitalized patients with elevated blood pressure (BP) in most cases should be treated with intensification of oral regimens, but are often given intravenous (IV) antihypertensives.

OBJECTIVE: To determine frequency of prescribing and administering episodic IV antihypertensives and outcomes.

DESIGN: Retrospective review.

SETTING: Urban academic hospital.

PATIENTS: Non-critically ill, hospitalized patients with an IV antihypertensive order for enalaprilat, labetalol, hydralazine, or metoprolol.

MEASUREMENTS: We analyzed BP thresholds for ordering and administering IV antihypertensives, the types and frequencies of IV antihypertensives administered, and the effect of IV antihypertensive use on short-term BP and adverse outcomes. The BP change during hospitalization was contrasted in those receiving IV antihypertensives between those who did and did not receive subsequent intensification of chronic oral antihypertensive regimens.

RESULTS: Two hundred forty-six patients had an episodic IV antihypertensive order. One hundred seventy-two patients received 458 doses, with 48% receiving a single dose. Over 98% of episodic IV antihypertensive doses were administered for systolic blood pressure (SBP) <200 mm Hg and 84.5% for SBP <180 mm Hg. Within 6 hours of administration, there was a statistically significant decline in average SBP and diastolic BP in patients receiving IV hydralazine and labetolol. After administration of IV antihypertensives, the oral inpatient medication regimen was adjusted in 52% of patients; these patients had a greater reduction in SBP from admission to discharge than patients with no change to their oral regimens. A total of 32.6% of patients receiving treatment experienced a BP reduction of more than 25% within 6 hours.

CONCLUSIONS: IV antihypertensive drugs are ordered and administered in patients with asymptomatic, uncontrolled BP for levels unassociated with substantive immediate cardiovascular risk, which may cause adverse effects.