Outcomes for mechanically ventilated COVID-19 patients better with ICU vs. high-dependency care

Patients with COVID-19 who received invasive mechanical ventilation in the ICU had reduced in-hospital mortality within 30 days compared with those who were treated in high-dependency care units, according to an observational study in Japan.

“To date, whether COVID-19 patients requiring invasive mechanical ventilation should be treated in the ICU or the high-dependency care unit is unknown,” Hiroyuki Ohbe, MD, from the department of clinical epidemiology and health economics at the School of Public Health at the University of Tokyo, and colleagues wrote. “Several societies have recommended that COVID-19 patients with invasive mechanical ventilation be treated in the ICU rather than the high-dependency care unit, based on an expert opinion without clear evidence.”

Ohbe and colleagues aimed to evaluate outcomes of COVID-19 patients with invasive mechanical ventilation who were treated in the ICU compared with the high-dependency care unit. The multicenter, observational, retrospective cohort study included 1,985 patients with COVID-19 who received care in ICUs at acute care hospitals in Japan (n = 1,303; median age, 65 years; 74% men) or high-dependency care units (n = 682; median age, 65 years; 76% men). All patients received invasive mechanical ventilation and were treated from February 2020 to November 2021.

The primary outcome was in-hospital mortality within 30 days from invasive mechanical ventilation initiation.

After the second day of invasive mechanical ventilation, 27% of patients treated in the ICU were transferred to the high-dependency care unit and 7% of patients treated in the high-dependency care unit were transferred to the ICU.

Patients with COVID-19 requiring invasive mechanical ventilation who were treated in the ICU had lower in-hospital mortality within 30 days compared with those treated in the high-dependency care unit (18.3% vs. 24.2%; P = .024) after propensity score matching. Researchers reported a significant difference in in-hospital mortality within 30 days between those who received care in the ICU vs. high-dependency care unit in a Kaplan-Meier analysis (P = .018).

Patients who received care in the ICU had lower ICU/high-dependency care unit mortality (13.3% vs. 19.4%; P = .010), longer mean time on invasive mechanical ventilation (20 days vs. 13 days; P = .008) and higher costs of hospitalization (7,290,000 yen vs. 5,290,000 yen; P < .001) compared with patients who received care in the high-dependency care unit.

“Because this study was an observational study, our finding represents an association, not a causation,” the researchers wrote. “Further studies of different critical care systems are warranted to confirm our findings.”