Predictors of mortality of mechanically ventilated patients in internal medicine wards

Budget restrictions have led to shortage of intensive care unit (ICU) beds in several countries. Consequently, ventilated patients are often kept on the wards. This study examined survival likelihood among patients ventilated on the wards and the predictive value of commonly used severity-of-illness scores.

This study is a prospective observation and characterization of consecutive, mechanically ventilated patients in 3 internal medicine wards of a single hospital who were denied ICU admission. Outcome measures are as follows: 28-day mortality, survival to hospital discharge, and 3 months postdischarge.

Eighty-six patients were examined. The patients were 78.9 ± 8.9 years old; 53% were independent preadmission. Respiratory insufficiency due to infection was the main reason for mechanical ventilation (58%). Charlson and acute physiology scores (APS) averaged 4 ± 2.2 and 91.8 ± 26.7, respectively. Twenty-eight-day mortality was 71%, whereas in-hospital mortality was 74% and 3 months postdischarge mortality was 79%. Survivors were significantly younger than nonsurvivors (74.4 ± 8.5 years vs 80.4 ± 8.6 years, P < .01), were more likely to be ventilated for cardiac causes (41% vs 11%, P = .04), and had significantly higher initial mean blood pressure (79.4 mm Hg vs 58.2 mm Hg, P = .02) and blood albumin levels (29.8 g/L vs 25.7 g/L, P = .05). Death rate was 10 times more likely, with an APS greater than 90 on the day of intubation as compared with an APS less than 90.

Mortality in patients ventilated on the ward was high, especially in the subgroup of patients with an APS score greater than 90. The early calculation of APS may assist in focusing therapeutic efforts on patients with better survival chances.