Abstract 75: Electronic Integrated Monitoring of Medical Emergency Team Calls to a Step Down Unit
Purpose: Early discharge from intensive care units (ICU) to lower acuity monitoring units (step-down units or SDU) is increasing to improve care throughput. However, the ability of minimally invasive monitoring via electronic integrated monitoring systems (IMS) in SDUs to identify cardiopulmonary deterioration in order to activate Medical Emergency Team (MET) response is unknown. We evaluated the ability of an IMS index value to detect clinically significant events which might trigger activation of the MET earlier than called.
Methods: Patients were monitored on a 24 bed trauma SDU according to prevailing policy and bedside decision making. An IMS (BioSignTM) was inserted into the monitoring system and IMS data were collected in a blinded fashion for 8 weeks from all patients. The IMS uses 4 parameters (heart rate [HR], respiratory rate [RR], blood pressure [BP], peripheral oxygen saturation [SpO2]) to develop a single neural networked signal known as the BioSign Index (BSI). Data were analyzed for patient deterioration according to both BSI trigger value and local MET criteria (DeVita, Qual Safety Health Care 2004).
Results: Data from 333 patient admissions were evaluated reflecting 18,692 hours of continuous monitoring. SpO2 monitoring data were absent in 38.5% of monitored hours, despite being mandatory. Most patients were stable throughout their SDU stay. MET activation occurred on 10 occasions (4 respiratory cause [2 SpO2, 2 SpO2+RR], 2 cardiac (BP), 1 mixed respiratory + cardiac, and 3 other (1 chest pain, 2 acute mental status change). All 7 MET events of respiratory and/or cardiac cause were detected by BSI in advance (mean advanced detection time prior to MET activation was 6.33 hours). Cardiopulmonary deterioration was generally characterized by progressive increases in BSI over time, not step increases.
Conclusion: In this population, cardiopulmonary deterioration requiring MET activation was uncommon but always preceded by IMS index elevations which would have alerted the nursing staff in advance. Continuous monitoring of physiological variables may be augmented by integrating information from multiple parameters to create a new variable. The new index parameter may detect patient deterioration earlier than single parameter monitoring.