Characteristics, treatment, outcomes and cause of death of invasively ventilated patients with COVID-19 ARDS in Milan, Italy

Objective: Describe characteristics, daily care and outcomes of patients with coronavirus disease 2019 (COVID-19) acute respiratory distress syndrome (ARDS). Design: Case series of 73 patients. Setting: Large tertiary hospital in Milan. Participants: Mechanically ventilated patients with confirmed COVID-19 admitted to the intensive care unit (ICU) between 20 February and 2 April 2020. Main outcome measures: Demographic and daily clinical data were collected to identify predictors of early mortality. Results: Of the 73 patients included in the study, most were male (83.6%), the median age was 61 years (interquartile range IQR, 54–69 years), and hypertension affected 52.9% of patients. Lymphocytopenia (median, 0.77 × 103 per mm3; IQR, 0.58–1.00 × 103 per mm3), hyperinflammation with C-reactive protein (median, 184.5 mg/dL; IQR, 108.2–269.1 mg/dL) and pro-coagulant status with D-dimer (median, 10.1 μg/m; IQR, 5.0–23.8 μg/m) were present. Median tidal volume was 6.7 mL/kg (IQR, 6.0–7.5 mL/kg), and median positive end-expiratory pressure was 12 cmH2O (IQR, 10–14 cmH2O). In the first 3 days, prone positioning (12–16 h) was used in 63.8% of patients and extracorporeal membrane oxygenation in five patients (6.8%). After a median follow-up of 19.0 days (IQR, 15.0–27.0 days), 17 patients (23.3%) had died, 23 (31.5%) had been discharged from the ICU, and 33 (45.2%) were receiving invasive mechanical ventilation in the ICU. Older age (odds ratio OR, 1.12; 95% CI, 1.04–1.22; P = 0.004) and hypertension (OR, 6.15; 95% CI, 1.75–29.11; P = 0.009) were associated with mortality, while early improvement in arterial partial pressure of oxygen (Pao2) to fraction of inspired oxygen (Fio2) ratio was associated with being discharged alive from the ICU (P = 0.002 for interaction). Conclusions: Despite multiple advanced critical care interventions, COVID-19 ARDS was associated with prolonged ventilation and high short term mortality. Older age and pre-admission hypertension were key mortality risk factors. Trial registration: ClinicalTrials.gov identifier: NCT04318366