Critically ill patients with severe acute respiratory syndrome (SARS) in a designated national SARS ICU: clinical features and predictors for mortality

Aim

An outbreak of SARS occurred in Singapore following the hospitalisation of the first index case on 1 March 2003. We report the clinical features and outcomes of critically ill probable SARS patients in a designated national SARS hospital.

Methods

We retrospectively reviewed the case records of all probable SARS patients admitted to a designated national SARS ICU from 1 March to 13 July 2003 when the last SARS patient was discharged.

Results

One hundred and ninety-nine probable SARS patients were admitted to this national SARS hospital. Forty-six (23.1%) required ICU admission. The mean age of these ICU patients was 49.8 ± 16.4 years with equal sex distribution and similar racial distribution as the national population. The mean APACHE II score was 19.2 ± 9.6. The median (interquartile range [IQR]) PaO₂/FiO₂ ratio on ICU admission was 88 (60–128). Eighty-five per cent required mechanical ventilation. Complications observed included: septicaemia 16 (34.8%), secondary pneumonia 24 (52.2%), deep vein thrombosis 11 (23.9%), acute renal failure 9 (19.6%), acute myocardial infraction 8 (17.4%), stress hyperglycaemia 8 (17.4%), pneumothorax 8 (17.4%), pulmonary embolism 7 (15.2%), cerebrovascular accidents 4 (8.7%) and pneumomediastinum 1 (2.2%). The in-ICU mortality was 54.3% (25/46). The median (IQR) length of mechanical ventilation was 12 (9–22) days. The median (IQR) lengths of stay in the hospital and ICU were 23.5 (15–36) days and 14.5 (7–22) days, respectively. Cox regression analysis showed that the male sex (P = 0.03), an APACHE II score > 15 (P = 0.003) and a history of congestive cardiac failure (0.017) were independent predictors for mortality among SARS ICU patients.

Conclusion

About one in five probable SARS patients required ICU care. This group of critically ill SARS patients has high mortality and morbidity. The predictors for ICU mortality were male sex, APACHE II score > 15 and history of congestive cardiac failure.