Outcomes in Temporary ICUs Versus Conventional ICUs: An Observational Cohort of Mechanically Ventilated Patients With COVID-19-Induced Acute Respiratory Distress Syndrome

Abstract

Throughout the COVID-19 pandemic, thousands of temporary ICUs have been established worldwide. The outcomes and management of mechanically ventilated patients in these areas remain unknown.

Objectives: To investigate mortality and management of mechanically ventilated patients in temporary ICUs.

Design setting and participants: Observational cohort study in a single-institution academic center. We included all adult patients with severe COVID-19 hospitalized in temporary and conventional ICUs for invasive mechanical ventilation due to acute respiratory distress syndrome from March 23, 2020, to April 5, 2021.

Main outcomes and measures: To determine if management in temporary ICUs increased 30-day in-hospital mortality compared with conventional ICUs. Ventilator-free days, ICU-free days (both at 28 d), hospital length of stay, and ICU readmission were also assessed.

Results: We included 776 patients (326 conventional and 450 temporary ICUs). Thirty-day in-hospital unadjusted mortality (28.8% conventional vs 36.0% temporary, log-rank test p = 0.023) was higher in temporary ICUs. After controlling for potential confounders, hospitalization in temporary ICUs was an independent risk factor associated with mortality (hazard ratio, 1.4; CI, 1.06-1.83; p = 0.016).There were no differences in ICU-free days at 28 days (6; IQR, 0-16 vs 2; IQR, 0-15; p = 0.5) or ventilator-free days at 28 days (8; IQR, 0-16 vs 5; IQR, 0-15; p = 0.6). We observed higher reintubation (18% vs 12%; p = 0.029) and readmission (5% vs 1.6%; p = 0.004) rates in conventional ICUs despite higher use of postextubation noninvasive mechanical ventilation (13% vs 8%; p = 0.025). Use of lung-protective ventilation (87% vs 85%; p = 0.5), prone positioning (76% vs 79%; p = 0.4), neuromuscular blockade (96% vs 98%; p = 0.4), and COVID-19 pharmacologic treatment was similar.

Conclusions and relevance: We observed a higher 30-day in-hospital mortality in temporary ICUs. Although both areas had high adherence to evidence-based management, hospitalization in temporary ICUs was an independent risk factor associated with mortality.

Keywords: COVID-19; acute lung injury; acute respiratory distress syndrome; intensive care unit; mechanical ventilation; mortality.

Figure 1.

Resource and personnel allocation. Conventional (left panel) and temporary (right panel) ICU total bed capacity and percent of personnel trained in critical care medicine. ICU-trained and non-ICU–trained nurse/physician:patient ratio.

Figure 2.

Kaplan-Meier curves. Thirty-day in-hospital mortality in conventional and temporary ICU areas. ICU survival at 30 d according to the area of hospitalization. p value was obtained with a Cox regression model stratifying for age and admission date and adjusting for potential confounders (gender, metabolic conditions, and ventilatory variables at ICU admission). The Kaplan-Meier analysis was unadjusted.

Figure 3.

Mortality through time in conventional and temporary. Thirty-day in-hospital mortality according to the month of hospital admission. Blue bars represent the total of patients who were either alive (soft blue) or dead (dark blue) per month. The red line depicts the monthly mortality rate’s mean (and gray shadow the CI) (conventional or temporary ICU areas). Solid lines represent survival and shaded areas at the 95% CI.