Temporal variability of medical emergency team calls

Introduction

We evaluated temporal variability of telephone calls to the medical emergency team (MET), as well as patient outcome.

Methods

All calls over a 48-month period between December 2005 and November 2009 were included. The time of telephone calls was noted, and occurrence throughout the day was studied. We compared the number of calls between 8:00 and 20:00 and between 20:00 and 8:00, using a Wilcoxon test. Patient's age, gender, reason for call, and outcome were entered into the ICU's database.

Results

In the 4-year period, there were 136 calls, amongst which 17 were erroneous (12.5%). Figure 1 shows the occurrence of calls throughout the day. Between 8:00 and 20:00 and between 20:00 and 8:00, there were respectively 93 and 43 calls (P = 0.02). The immediate causes of intervention were cardiac arrest in 35%, respiratory depression in 8%, and decreased level of consciousness in 43% of cases (other: 14%). Eighteen percent of patients died during MET intervention. Amongst survivors, 31% were transferred in the ICU. Involved patients' age was 67 ± 17 (male: 53%).

Figure 1

Occurrence of calls throughout the day.

Conclusions

Reporting data might have less accuracy during nights. Nevertheless, despite difficulty of capturing such data, our series suggests that there is a temporal variability of medical emergency team calls. The fact that the majority of calls occurred between 8:00 and 20:00 may probably be a reflection of the level of supervision and the general amount of patient activity within the hospital during the day.