Abstract
BACKGROUND: COVID-19 emerged as a global health crisis with multiple waves of infection ranging from asymptomatic to critical cases requiring intensive care. In Pakistan, dearth of ICU data limit understanding of critical care admissions and outcomes, making it difficult to understand critical care admissions and outcomes. This study aims to describe demographics, clinical characteristics, and outcomes of patients with SARS-CoV-2 infection admitted to 69 intensive care units (ICUs) during five waves of pandemic in Pakistan. METHODS: This study analyzed prospectively collected data of adult COVID-19 patients admitted to Pakistan Registry of Intensive Care (PRICE) ICUs from April 2020 to March 2022. RESULTS: 9,102 ICU admissions were reported during the study period, with highest in Wave 1 (n = 2,704) and Wave 2 (n = 2,563). Most admissions were male, and predominant age group was 60–79 years. Patients aged > 80 years increased from 8.9% in Wave 4 to 18.6% in Wave 5. Common presenting symptoms were shortness of breath, fever, and cough with no sputum. Highest mortality was recorded during Waves 3 and 4 (41%). Among patients requiring organ support, mortality increased from 50% in Wave 1 to 65% in Wave 4. Cox regression showed younger age, low oxygen saturation, and cardiovascular disease were associated with higher risk of invasive mechanical ventilation (IMV). CONCLUSION: Mortality was highest during Waves 3 and 4, particularly among patients requiring organ support. Younger patients, those with low oxygen saturation, and individuals with cardiovascular diseases were at increased risk for IMV. CLINICAL TRIAL NUMBER: Not applicable. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12879-026-13012-3.