Adaptive threshold-based alarm strategies for continuous vital signs monitoring

Abstract

Continuous vital signs monitoring in post-surgical ward patients may support early detection of clinical deterioration, but novel alarm approaches are required to ensure timely notification of abnormalities and prevent alarm-fatigue. The current study explored the performance of classical and various adaptive threshold-based alarm strategies to warn for vital sign abnormalities observed during development of an adverse event. A classical threshold-based alarm strategy used for continuous vital signs monitoring in surgical ward patients was evaluated retrospectively. Next, (combinations of) six methods to adapt alarm thresholds to personal or situational factors were simulated in the same dataset. Alarm performance was assessed using the overall alarm rate and sensitivity to detect adverse events. Using a wireless patch-based monitoring system, 3999 h of vital signs data was obtained in 39 patients. The clinically used classical alarm system produced 0.49 alarms/patient/day, and alarms were generated for 11 out of 18 observed adverse events. Each of the tested adaptive strategies either increased sensitivity to detect adverse events or reduced overall alarm rate. Combining specific strategies improved overall performance most and resulted in earlier presentation of alarms in case of adverse events. Strategies that adapt vital sign alarm thresholds to personal or situational factors may improve early detection of adverse events or reduce alarm rates as compared to classical alarm strategies. Accordingly, further investigation of the potential of adaptive alarms for continuous vital signs monitoring in ward patients is warranted.

Wearable devices to monitor recovery after abdominal surgery: scoping review

“…Vital sign changes are the fundamental components behind early-warning score systems that have been introduced worldwide to recognize deteriorating patients 8 ; however, intermittent vital sign measurement often misses significant postoperative hypotension, hypoxemia, and apnoea 41 , 101 , 102 , with potential clinical consequences. Continuous monitoring of vital signs and early-warning score data in real-time may allow for earlier detection of vital sign changes, recognition of early signs of complications, and a faster time to intervention 103–105 . Using wearable devices is clearly preferable to traditional wired bedside monitors; however, technical challenges of accuracy, precision, and data transfer remain incompletely solved.…”

Nurses’ experiences with continuous vital sign monitoring on the general surgical ward: a qualitative study based on the Behaviour Change Wheel

“…Therefore, for general wards more sophisticated alarm strategies would be desirable, but these are still under development. 39 Alternatively, strategies relying on routine trend assessments only (e.g. several times per day) rather than using pre-set alarms may be a solution to deal with excessive alarms and support implementation and compliance on general wards.…”

Feasibility of wireless continuous monitoring of vital signs without using alarms on a general surgical ward: A mixed methods study

“…So, part of the routine manual measurements was retained which may have increased total work load and affected nurse acceptability. However, considering the rapid developments in sensor technology and systems, expansion of measurable vital signs, more than just HR and RR, and improvement of clinical decision support tools and alarm strategies by algorithms [16,48], it seems only a matter of time before these manual measurement routines become obsolete. Third, in support of the interpretation of vital sign trends by nurses, only very limited digital tools are currently available.…”