Observations and warning signs prior to cardiac arrest.: Should a medical emergency team intervene earlier?

Background: The Medical Emergency Team (MET) has evolved in some hospitals as a means of delivering effective treatment early enough to prevent cardiac arrests. Our aim was to analyze the effectiveness of observation practice to detect abnormalities in vital signs prior to cardiac arrest and to determine the need for a MET system in Finnish hospitals. Methods: The charts of patients who suffered cardiac arrest during 18 months in four hospitals were reviewed. The vital signs, symptoms and interventions during 8 h prior to arrest were recorded and analyzed against trigger criteria of the MET. Results: During the study period, 110 patients suffered cardiac arrest in hospitals, and 56 (51%) of the arrests occurred on the wards. Of those patients, 30 (54%) had an abnormal vital sign fulfilling the MET criteria, documented on average 3.8 h prior to the arrest. During this period, 13 patients did not receive any intervention (e.g. supplemental oxygen or medication), eight received intervention within 1 h and nine received intervention after more than 1 h. Response to the first intervention was not attained in any patient; nevertheless re-interventions took place in one patient only. Conclusion: Significant physiological deterioration seems to be common in the hours before a cardiac arrest on the wards of Finnish hospitals, suggesting that implementation of a MET-system may be worthwhile. However, the practice of vital sign observation by the nursing staff should be improved before maximal benefit of a MET can be achieved.