PLATELET COUNT AS A PROGNOSTIC MARKER FOR ACUTE RESPIRATORY DISTRESS SYNDROME

Abstract

Background: Acute respiratory distress syndrome (ARDS) is a severe inflammatory lung condition associated with substantial morbidity and mortality.

Objective: To assess whether platelet count at baseline can be used to predict in-hospital mortality at 28 days in ARDS.

Methods: This was a prospective observational cohort study of 93 patients aged 18–60 years, who met Berlin criteria for ARDS at Jinnah Postgraduate Medical Centre, Karachi. Platelet count was obtained at the time of intensive care unit admission as a baseline value. Patients were followed for 28 days or until they were discharged from hospital or died. Demographic, clinical, laboratory, ARDS severity, mechanical ventilation and outcome data were documented. Binary logistic regression and receiver operating characteristic (ROC) curve analyses were conducted.

Results: The mean age of participants was 44.8±11.3 years, and 58 (62.4%) were male. Overall, 37 (39.8%) patients died within 28 days. The median platelet count was significantly lower among non-survivors than survivors (76 [42–119] versus 154 [108–211] ×10⁹/L; p<0.001). The mortality rate was higher in patients with platelet counts ≤100×10⁹/L (58.7%) versus those with higher platelet counts (21.3%). The platelet count ≤100×10⁹/L was still an independent predictive factor for mortality after adjustment for age, sex, chronic obstructive pulmonary disease, the severity of ARDS and mechanical ventilation (adjusted OR 3.84, 95% CI 1.35-10.93, p=0.012). The area under the curve was 0.79.

Conclusion: Baseline platelet count was independently associated with 28-day mortality in ARDS and seemed to be a simple, readily available prognostic tool.