Short-term outcome of critically ill patients with severe acute respiratory syndrome

Abstract

Objective: To document the outcome and determine prognostic factors for patients with severe acute respiratory syndrome who require admission to an intensive care unit.

Design: Observational cohort study involving retrospective analysis of demographic, clinical, laboratory and radiological data.

Setting: Adult intensive care unit in a tertiary referral university hospital involved in a major outbreak of severe acute respiratory syndrome (SARS).

Patients: The first 54 patients admitted with SARS to an intensive care unit (ICU). All were treated with corticosteroids, ribavirin, broad spectrum antimicrobials and supportive therapy.

Interventions: None.

Measurements and results: All patients were admitted for respiratory failure. The median APACHE II score was 11 (interquartile range 8-13). At 28 days 34 patients (63%; 95% CI 49.6-74.6) were alive and not mechanically ventilated. Six patients were alive but ventilated (11.3%; 95% confidence interval 5.3-22.6) and 14 had died (25.9%; CI 16.1-38.9). Seven of 27 ventilated patients developed evidence of barotrauma (25.9%; 95% CI 13.2-44.7). Median maximal multiple-organ dysfunction score was 5 (interquartile range 3.3-9). Median maximal respiratory dysfunction score was 3 (interquartile range 3-4). Increased age, severity of illness, lymphocyte count, decreased steroid dose, positive fluid balance, chronic disease or immunosuppression and nosocomial sepsis were associated with poor outcome on univariate analysis. Poor outcome was defined as death or need for mechanical ventilation at 28 days after ICU admission.

Conclusions: Mortality amongst critically ill patients with SARS is high. It causes predominantly severe respiratory failure, with little other organ failure, and a high incidence of barotrauma amongst those requiring mechanical ventilation.