Treatment of Hypertension in the Inpatient Setting: Use of Intravenous Labetalol and Hydralazine

Abstract

J Clin Hypertens (Greenwich). 2010;12:29–33. ©2009 Wiley Periodicals, Inc. Acute blood pressure elevations are commonly treated in hospitalized patients. There are no guidelines for appropriate practice and no evidence that such treatment is useful. The authors performed a retrospective review of medical and pharmacy records to determine how often intravenous hydralazine and labetalol are ordered and administered. During a 1‐year study period, a total of 29,545 hospitalizations were recorded. The authors identified 2189 patients (7.4% of all patients) for whom 7242 orders were written for hydralazine as needed (10–20 mg per dose) and 5915 for labetalol (10–20 mg per dose). Ordered drugs were adminstered in 60.3% of patients, and the average number of doses administered was 5.3±8.2 (mean ± SD) for hydralazine and 5.6±7.7 for labetalol. Hospital length of stay (LOS) for patients for whom hydralazine was ordered was 12.0±15.9 days for those who received at least 1 dose and 7.1±9.0 days for those who did not receive a dose (P<.001). For patients for whom labetalol was ordered, patients receiving at least 1 dose had an LOS of 11.8±16.1 days vs 7.9±10.4 days for those who did not receive a dose (P<.001). Treatment of elevated blood pressure in in‐patients is a common practice. The authors suggest that evidence is needed to determine whether the practice is of benefit.

Treating Acute Hypertension in the Hospital

“…Using these prevalence figures, during a 1-year period (October 1, 2007, to September 30, 2008) in which there were 29 545 adult admissions to UMHS, some 11 100 patients were probably hypertensive. 7 Even this estimate is lower than that suggested by the results of a survey of UMHS full-time hospitalists (nϭ31), in which the modal estimate of the prevalence of established hypertension was 50% (Figure 1, left panel). In addition, patients without previously diagnosed hypertension will be encountered ( Figure 1, right panel), and even normotensive patients may experience situations (eg, anxiety or pain) that provoke transient hypertension.…”

“…Dr Erickson and I previously examined the use of 2 agents frequently used at UMHS for treatment of acute hypertension (and probably for little else): intravenous labetalol and hydralazine. 7 These drugs are usually effective in lowering BP, but because there is no proven benefit of treatment, the potential exists for an adverse risk-benefit ratio.…”

“…Of patients who have "as-needed" treatment with intravenous labetalol or hydralazine ordered at admission for a BP above an arbitrary threshold, those who actually receive such treatment have much longer hospitalizations than those for whom treatment is ordered but not administered: hospital length of stay was 10.6Ϯ13.1 days (meanϮSD) for patients receiving hydralazine, 9.6Ϯ11.1 days for those receiving labetalol, 13.5Ϯ18.9 days for patients who received both drugs, and 6.5Ϯ9.7 days for patients for whom drugs were ordered but not administered. 7 Although it is likely that patients treated for acute hypertension are sicker or are cared for in settings in which aggressive BP control is deemed appropriate (eg, intensive care units), only 2.9% had ICD-9 codes documenting conditions typically thought to require prompt BP lowering (ICD-9 codes 437.2 7 Although we do not know why UMHS patients treated with intravenous antihypertensives have longer lengths of stay, and we do not know how prevalent this phenomenon is outside our system, because of the possible cost implications, further investigation is warranted. Although only about a third of UMHS physicians believe that a markedly elevated BP should prompt intensive care unit transfer, they overwhelmingly assert that there is a level of BP that should delay discharge in patients otherwise deemed fit to go home.…”

48-Year-Old Man With Cough and Leg Swelling

“…It has been suggested that most patients in hypertensive crises are treated inappropriately. 4,5 Only 15% of patients in the Studying the Treatment of Acute Hypertension registry received a continuous IV infusion of antihypertensive as first-line treatment. 6 In hypertensive urgencies, gradual lowering of BP over a 24-to 48-hour period using oral medications is the recommended approach.…”

Management of Hypertensive Emergencies

“…It is often used as an antihypertensive on a PRN basis in the inpatient setting even for asymptomatic elevation of blood pressures [36]. It has an initial latent period of 5-15 minutes followed by a precipitous fall in blood pressure, with effects lasting up to 10 hours [37,38]. It is not recommended for use in hypertensive crisis because of its unpredictable antihypertensive effect and difficulty in titration [39].…”