2.1 Inclusion criteria
According to the diagnostic and classification criteria of the National Institute of Health [NIH] Pakistan,14 following criteria were used to enroll the patients admitted in the ICU of DHQ Hospital, Faisalabad due to COVID-19 associated pneumonia:
  1. Age > 18 years.
  2. Patients who met the diagnostic criteria of NIH PakistanĀ for COVID-19 infection, which are as follows:
  3. Clinical manifestations including fever and pulmonary symptoms (cough, shortness of breath, chest pain, and tightness).
  4. Radiological findings of consolidation, ground-glass opacities (GGOs) either on chest X-ray or high-resolution computed tomography (HRCT).
  5. Real-time fluorescent reverse transcription-polymerase chain reaction (RT-PCR) of respiratory samples (nasal/oropharyngeal swab or tracheal secretions) positive for SARS-CoV-2. The laboratory confirmation of SARS-CoV-2 infection was carried out by the local health department.