Video Analysis of Factors Associated With Response Time to Physiologic Monitor Alarms in a Children's Hospital

Abstract

Importance: Bedside monitor alarms alert nurses to life-threatening physiologic changes among patients, but the response times of nurses are slow.

Objective: To identify factors associated with physiologic monitor alarm response time.

Design, setting, and participants: This prospective cohort study used 551 hours of video-recorded care administered by 38 nurses to 100 children in a children's hospital medical unit between July 22, 2014, and November 11, 2015.

Exposures: Patient, nurse, and alarm-level factors hypothesized to predict response time.

Main outcomes and measures: We used multivariable accelerated failure-time models stratified by each nurse and adjusted for clustering within patients to evaluate associations between exposures and response time to alarms that occurred while the nurse was outside the room.

Results: The study participants included 38 nurses, 100% (n = 38) of whom were white and 92% (n = 35) of whom were female, and 100 children, 51% (n = 51) of whom were male. The race/ethnicity of the child participants was 45% (n = 45) black or African American, 33% (n = 33) white, 4% (n = 4) Asian, and 18% (n = 18) other. Of 11 745 alarms among 100 children, 50 (0.5%) were actionable. The adjusted median response time among nurses was 10.4 minutes (95% CI, 5.0-15.8) and varied based on the following variables: if the patient was on complex care service (5.3 minutes [95% CI, 1.4-9.3] vs 11.1 minutes [95% CI, 5.6-16.6] among general pediatrics patients), whether family members were absent from the patient's bedside (6.3 minutes [95% CI, 2.2-10.4] vs 11.7 minutes [95% CI, 5.9-17.4] when family present), whether a nurse had less than 1 year of experience (4.4 minutes [95% CI, 3.4-5.5] vs 8.8 minutes [95% CI, 7.2-10.5] for nurses with 1 or more years of experience), if there was a 1 to 1 nursing assignment (3.5 minutes [95% CI, 1.3-5.7] vs 10.6 minutes [95% CI, 5.3-16.0] for nurses caring for 2 or more patients), if there were prior alarms requiring intervention (5.5 minutes [95% CI, 1.5-9.5] vs 10.7 minutes [5.2-16.2] for patients without intervention), and if there was a lethal arrhythmia alarm (1.2 minutes [95% CI, -0.6 to 2.9] vs 10.4 minutes [95% CI, 5.1-15.8] for alarms for other conditions). Each hour that elapsed during a nurse's shift was associated with a 15% longer response time (6.1 minutes [95% CI, 2.8-9.3] in hour 2 vs 14.1 minutes [95% CI, 6.4-21.7] in hour 8). The number of nonactionable alarms to which the nurse was exposed in the preceding 120 minutes was not associated with response time.

Conclusions and relevance: Response time was associated with factors that likely represent the heuristics nurses use to assess whether an alarm represents a life-threatening condition. The nurse to patient ratio and physical and mental fatigue (measured by the number of hours into a shift) represent modifiable factors associated with response time. Chronic alarm fatigue resulting from long-term exposure to nonactionable alarms may be a more important determinant of response time than short-term exposure.

Figure 1

Alarm data flow diagram. The analysis examined response time to the 3280 “out-of-room” alarms that (a) occurred while no clinicians were in the patient’s room or were viewing the central monitoring station, and (b) sent automatic text messages to the bedside nurse (alarms for asystole, ventricular tachycardia, ventricular fibrillation, apnea, HR, RR, SpO₂, probe off, and leads fail).