Reducing Unnecessary Treatment of Asymptomatic Elevated Blood Pressure with Intravenous Medications on the General Internal Medicine Wards: A Quality Improvement Initiative
BACKGROUND: Asymptomatic elevated blood pressure (BP) is common in the hospital. There is no evidence supporting the use of intravenous (IV) antihypertensives in this setting.
OBJECTIVE: To determine the prevalence and effects of treating asymptomatic elevated BP with IV antihypertensives and to investigate the efficacy of a quality improvement (QI) initiative aimed at reducing utilization of these medications.
DESIGN: Retrospective cohort study.
SETTING: Urban academic hospital. PATIENTS: Patients admitted to the general medicine service, including the intensive care unit (ICU), with ≥1 episode of asymptomatic elevated BP (>160/90 mm Hg) during hospitalization.
INTERVENTION: A two-tiered, QI initiative.
MEASUREMENTS: The primary outcome was the monthly proportion of patients with asymptomatic elevated BP treated with IV labetalol or hydralazine. We also analyzed median BP and rates of balancing outcomes (ICU transfers, rapid responses, cardiopulmonary arrests).
RESULTS: We identified 2,306 patients with ≥1 episode of asymptomatic elevated BP during the 10-month preintervention period, of which 251 (11%) received IV antihypertensives. In the four-month postintervention period, 70 of 934 (7%) were treated. The odds of being treated were 38% lower in the postintervention period after adjustment for baseline characteristics, including length of stay and illness severity (OR = 0.62; 95% CI 0.47-0.83; P = .001). Median SBP was similar between pre- and postintervention (167 vs 168 mm Hg; P = .78), as were the adjusted proportions of balancing outcomes.
CONCLUSIONS: Hospitalized patients with asymptomatic elevated BP are commonly treated with IV antihypertensives, despite the lack of evidence. A QI initiative was successful at reducing utilization of these medications.
© 2019 Society of Hospital Medicine
Secondary Outcomes
To investigate blood pressure trends over time, we analyzed BP in three ways. First, we analyzed the median SBP for the entire population. Second, to determine clinical responses to IV antihypertensive medications among patients receiving treatment, we calculated the population medians for the pretreatment SBP, the change in SBP from pretreatment baseline, and the posttreatment SBP. Third, we calculated the average median SBP on a monthly basis for the duration of the study. This was achieved by calculating the median value of all SBPs for an individual patient, then averaging across all patients in a given month. The average monthly median SBPs are displayed in the lower portion of the Figure.
To investigate whether the intervention was associated with negative patient outcomes, the proportions of several balancing outcomes were compared between pre- and postintervention periods, including ICU transfers, rapid response calls, and code blues (cardiopulmonary arrests).
Development and Implementation of an Intervention to Reduce Excessive IV Antihypertensive Use
After establishing the baseline prevalence of IV antihypertensive medication use at our institution, we developed a QI initiative with the goal of reducing IV antihypertensive medication utilization by the general medicine service for the treatment of asymptomatic patients. We hypothesized that potential contributors to overutilization might include lack of education, provider/nursing discomfort, and a system designed to mandate provider notification for even modestly elevated BPs. The QI initiative, which took place between October 2017 and December 2017, was designed to address these potential contributors and was comprised of a division-wide, two-tiered, bundled intervention. Our choice of a two-tiered approach was based on the fact that successful culture change is challenging, along with the existing evidence that multifaceted QI interventions are more often successful than single-tiered approaches.19
The first tier of the initiative included an educational campaign referred to colloquially as “NoIVForHighBP,” which targeted residents, hospitalists, and nursing staff. The campaign consisted of a series of presentations, best practice updates, handouts, and posters displayed prominently in shared workspaces. The educational content focused on alternative approaches to the management of asymptomatic elevated BP in the hospital, such as identification and treatment of pain, anxiety, volume overload, or other contributing factors (see supplemental materials). These educational outreaches occurred periodically between October 4, 2017 and November 20, 2017, with the bulk of the educational efforts taking place during November. Therefore, November 1, 2017 was designated the start date for the intervention period.
The second tier of the intervention included the liberalization of the EHR BP notification parameters on the standard inpatient admission order set from >160/90 mm Hg to >180/90 mm Hg. This change took effect on 12/6/2017. The decision to modify the BP notification parameters was based on the hypothesis that mandatory notifications for modestly elevated BPs may prompt providers to reflexively order IV antihypertensive medications, especially during times of cross-coverage or high clinical workload.
Statistical Analysis
All statistical analyses were performed using Stata software version 15 (StataCorp. 2017. Stata Statistical Software: Release 15. College Station, Texas: StataCorp LLC). Baseline patient characteristics were compared using nonparametric tests of significance. Population median SBPs were compared between pre- and postintervention periods using Mood’s Median Test, which was selected because the data were distributed nonnormally, and variances between samples were unequal.
