Admission into an intensive care unit (ICU) is reserved for those people who are critically ill or in an unstable condition. People in ICU are usually monitored using specialist equipment by clinical staff with a high level of expertise in order to help recovery from, or prevention of, a severe clinical event (NHS Choices 2015).
Monitoring people's vital signs outside an ICU often relies on nursing staff conducting checks at set intervals. However, if the patient deteriorates between monitoring times, there may be a delay in detecting the change in their condition. Continuous monitoring of people's vital signs, in particular heart rate (HR) and respiratory rate (RR), may provide a mechanism to alert doctors or nurses of an imminent severe clinical event. The NICE guideline on acute illness in adults in hospital recommends that physiological parameters, including HR and RR, should be monitored at least every 12 hours. These physiological observations provide the basis for risk stratification of patients using systems such as the National Early Warning Score System (which uses respiratory rate, oxygen saturation, temperature, systolic blood pressure, pulse rate and level of consciousness; Royal College of Physicians 2012). Patients are assessed upon admission and those with low deterioration risk scores have at least 12‑hourly monitoring (as recommended in the NICE guideline on acute illness in adults in hospital, section 1.3). Higher scores necessitate more extensive monitoring.
The EarlySense system has a potentially broad range of applications, 1 of which would be in non‑critical care hospital settings for continuous monitoring of patients' HR and RR, which is the focus of this briefing. Continuous monitoring could provide medical staff with the means to identify patients at risk of clinical deterioration, leading to fewer adverse events such as cardiac arrest, respiratory failure and death (Landrigan et al. 2010). Additional modular software, which can monitor patient movement in bed, as well as bed exit (fall risk) is outside the scope of this briefing.