Prospective assessment of the standardized mortality ratio (SMR) as a measure of quality of care in an intensive care unit - a single-centre study

Background: The standardized mortality ratio (SMR) is a recognized indicator of critical care quality. This ratio is used to compare actual hospital mortality of all patients treated in an Intensive Care Unit (ICU) with predicted mortality. The aim of this study was a prospective analysis of SMR as a measure of the quality of care in a single ICU. Methods: A prospective study was performed during a 12-month period in the ICU of the Czerniakowski Hospital in Warsaw. Predicted hospital mortality was calculated using the SAPS 3 model. The value of the SMR was evaluated in three risk groups (low, moderate, and high risk) and included the surgical status of patients (nonoperative, after elective or emergency surgery). Results: A total of 341 patients were included. The SMR in the general population was 0.98 (95% CI 0.74-1.28). In the low-and high-risk groups, the value of the SMR did not differ significantly from 1. In the average risk group, as well as among patients undergoing elective surgery, the value of the SMR tended to exceed 1. Conclusions: In groups of patients with low and high risk, the values of the SMR indicated a favourable quality of care. Study results should prompt a detailed analysis of the course of treatment for patients with an average risk of death. Analysis of the treatment course and qualification criteria for surgery in patients undergoing elective surgery is also indicated.