Safety of Intermittent Parenteral Midazolam Injection in Hospitalized Patients Admitted to Non-Intensive Care Nursing Units: A Retrospective Matched-Cohort Study

Melanie Mills, Maine Medical Center, Portland, ME, USA.
Haley Torr, Maine Medical Center, Portland, ME, USA.
Nicolette Centanni, Maine Medical Center, Portland, ME, USA.
Richard R. Riker, Maine Medical Center, Portland, ME, USA.
David Gagnon, Maine Medical Center, Portland, ME, USA.

Abstract

BACKGROUND: The prescribing information for parenteral midazolam contains a Boxed Warning stating its use may precipitate respiratory arrest, and its safety in non-intensive care unit (ICU) nursing units has been understudied. OBJECTIVE: To characterize the safety of intermittent midazolam injections in patients admitted to non-ICU nursing units relative to lorazepam injections. METHODS: This single-center, retrospective, matched-cohort study included patients ≥18 years of age who received intermittent midazolam in non-ICU nursing units. Midazolam administrations were matched 1:1 to lorazepam administrations. Safety outcomes included hypotension, bradycardia, bradypnea, and escalation in level of nursing unit care or oxygen requirement. RESULTS: A total of 94 midazolam administrations were matched to lorazepam administrations. Demographic data were similar between groups. Midazolam was more commonly given intravenously (95.7% vs 85.1%, P = 0.02) and in an intermediate care nursing unit (31.9% vs 14.9%, P = 0.009). The lorazepam cohort had significantly fewer concomitant respiratory depressants administered, and there were no differences in the use of beta-blockers or antihypertensives. There were no differences in the incidence of hypotension (1.1% vs 2.1%, P = 1), bradycardia (5.3% vs 2.1%, P = 0.44), bradypnea (1.1% vs 0%, P = 1), escalation in level of care (2.1% vs 2.1%, P = 1), or escalation in oxygen requirement (5.3% vs 3.2%, P = 0.72). CONCLUSION AND RELEVANCE: The administration of parenteral midazolam in non-ICU nursing units resulted in a similar incidence of hypotension, bradycardia, bradypnea, escalation in oxygen requirement, and escalation in level of care compared with lorazepam. These results suggest that midazolam may have a similar safety profile to lorazepam, supporting its use in non-ICU nursing units.