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 x 10(3) per mm(3); IQR, 0.58-1.00 x 10(3) per mm(3)), 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 mu g/m; IQR, 5.0-23.8 mu g/m) were present. Median tidal volume was 6.7 mUkg (IQR, 6.0-7.5 mL/kg), and median positive end-expiratory pressure was 12 cmH(2)O (IQR, 10-14 cmH(2)O). 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 followup 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 (Pao(2) ) to fraction of inspired oxygen (Fio(2)) 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.