JMIR Publications

ABSTRACT

Background:

Many studies have evaluated the use of Wearable Monitoring Systems (WMS) to improve patient safety in hospital. Although some have demonstrated effects on intensive care admissions, there remains little evidence of impact on patient outcomes such as mortality, hospital length of stay and time to antibiotic administration. Very few studies have focussed on how WMS is used in clinical practice, including how the rate of manual vital signs measurements (MVSM) is affected.

Objective:

Our primary aim was to describe the physiological pattern of vital signs in hospitalised patients treated for COVID-19 infection outside of critical care. We also report exploratory post-hoc analysis of the impact of displaying WMS data on the frequency of intermittent MVSM.

Methods:

We conducted a retrospective study during the COVID-19 pandemic following deployment of a WMS that continuously displayed heart rate, respiratory rate and oxygen saturation levels. We included patients treated for COVID-19 on three isolation wards in a large UK hospital. WMS data were displayed on a dashboard in the centre of each ward. We analysed vital signs patterns in patients monitored with WMS. We compared the time to next observation (led by nursing staff) for routinely collected MVSM between periods when patients were continuously monitored versus when they were not. In exploratory post-hoc analysis, we tested whether the difference varied between stable (Early Warning Score above the escalation threshold) and unstable patients.

Results:

Patients (n=144) had continuous vital signs above the EWS threshold for escalation for 32.7% (2,133 hours) of time monitored. The median time between MVSM for continuously monitored periods was 39 minutes (95% CI 29-49, P<.001) longer than for unmonitored periods. The median time between MVSM observations in stable patients was 51 minutes (95% CI 39-62, P<.001) compared with 16 minutes (95% CI 8-24, P<.001) in unstable patients.

Conclusions:

Patients in this study were at elevated risk of deterioration, spending a third of monitored time at or above the escalation threshold. In exploratory post-hoc analysis, we found that by offering additional vital-sign data between manual measurements, the wearable monitoring system may have reduced nursing workload by allowing nursing staff to extend the time between routine manual vital-sign measurements in stable patients. We found no evidence that reducing observation frequency in stable patients adversely affected patient safety. Clinical Trial: Study registration: ISRCTN 85624923