Acute Respiratory Distress Syndrome in Critically Ill Patients with Severe Acute Respiratory Syndrome

Abstract

Context: Severe acute respiratory syndrome (SARS) is an emerging infectious disease with a 25% incidence of progression to acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) and mortality exceeding 10%. Objective: To describe the clinical spectrum and outcomes of ALI/ARDS in patients with SARS-related critical illness. Design, Setting, and Patients: Retrospective case series of adult patients with probable SARS admitted to the intensive care unit (ICU) of a hospital in Singapore between March 6 and June 6, 2003. Main Outcome Measures: The primary outcome measure was 28-day mortality after symptom onset. Results: Of 199 patients hospitalized with SARS, 46 (23%) were admitted to the ICU, including 45 who fulfilled criteria for ALI/ARDS. Mortality at 28 days for the entire cohort was 20 (10.1%) of 199 and for ICU patients was 17 (37%) of 46. Intensive care unit mortality at 13 weeks was 24 (52.2%) of 46. Nineteen of 24 ICU deaths occurred late (≥7 days after ICU admission) and were attributed to complications related to severe ARDS, multiorgan failure, thromboembolic complications, or septicemic shock. ARDS was characterized by ease of derecruitment of alveoli and paucity of airway secretion, bronchospasm, or dynamic hyperinflation. Lower Acute Physiology and Chronic Health Evaluation II scores and higher baseline ratios of PaO 2 to fraction of inspired oxygen were associated with earlier recovery. Conclusions: Critically ill patients with SARS and ALI/ARDS had characteristic clinical findings, high rates of complications; and high mortality. These findings may provide useful information for optimizing supportive care for SARS-related critical illness.