Correlation Between Monitoring Frequency and Clinical Deterioration in Hospitalized Patients

Acute deterioration among hospitalised patient can result in serious adverse events like cardiac arrest, unexpected death or unanticipated intensive care unit (ICU) admission. Most events are preceeded by deteriorating vital signs, and potentially avoidable.

To detect and treat hospitalised patients at risk of clinical deterioration in a timely manner, an early warning score (EWS) was introduced at the investigator site. EWS includes measures for respiratory rate, arterial hemoglobin oxygen saturation, pulse rate, systolic blood pressure, level of consciousness according to AVPU score, temperature, and whether a patient receives supplementary oxygen. Each vital sign can be assigned between 0 to 3 points (supplementary oxygen 0 or 2) depending on how much it deviates from a predefined threshold; the values are added to an aggregated score from 0 to 20, higher scores indicating more severe disease. An escalation protocol that directs the type of clinical response and competency of the provider according to EWS triggers was also introduced as an integrated part of the system.

Patients with low scores (0 - 1) are monitored every 12th hour and seldom experience serious adverse events. The optimal monitoring frequency for this group is unknown, and presently based on a compromise between patient safety and work load issues.

The aim of the present study is to explore if an 8 hourly monitoring interval (intervention) is correlated with a better outcome than 12 hour intervals (control) in the group of patients that have an EWS of 0 or 1 on admission. Deterioration is based on the number of patients that deteriorate to a higher EWS 24 hours after the first EWS is measured. Since serious adverse events in this population are rare the primary outcome is clinical deterioration defined as number of patients with elevated EWS >/= 2 in each group, 24 hours after admission to the hospital.

This is a cluster-randomized, non-blinded, pragmatic, interventional study of acutely admitted, adult patients to surgical or medical wards at our hospital.

Inclusion criteria

• first EWS on admission = 0 or 1
• age >/ = 18 years

Exclusion criteria

• chronically elevated EWS
• terminal disease and comfort care only
• conditions that warrant closer observation according to hospital guidelines