Observed versus predicted hospital mortality in general wards patients assisted by a medical emergency team

Introduction. In many countries the demand for intensive care beds exceeds their availability. The Medical Emergency Team (MET) can manage critically ill patients outside the intensive care unit (ICU). Hospital mortality rate for patients admitted to general wards and assisted by the MET was never compared to the predicted mortality for the same group of patients in an ICU setting. Methods. Single-centre, prospective, observational study on consecutive adult patients assisted by the MET in all general wards and in the Emergency Department of a 1100-bed teaching Hospital. Patients with a 'do-not-attempt-resuscitation' decision were excluded. Results. Eighty-two consecutive patients were included. Observed hospital mortality was 34.1% (28 patients), while the Simplified Acute Physiology Score II (SAPS II) predicted a mortality for the first MET visit of 17% (p=0.02). Patients transferred to an ICU, but not during the first MET evaluation (delayed ICU admission), had worse than predicted outcomes, while patients immediately transferred to an ICU showed hospital mortality similar to the predicted one. The fifty patients treated for acute respiratory failure (especially those with pneumonia - 12 patients) had the worst observed/predicted hospital mortality ratio (3.0 for acute respiratory failure, p=0.02; 8.06, p=0.03 for pneumonia patients). Conclusions. Critically ill patients who remained in general wards or who were admitted to the ICU with some delay had markedly higher hospital mortality than the SAPS II predicted hospital mortality, even if they were assisted by the MET.