Long-term mortality and health-related quality of life with lower versus higher oxygenation targets in intensive care unit patients with COVID-19 and severe hypoxaemia.

Abstract

The aim of this study was to evaluate one-year outcomes of lower versus higher oxygenation targets in intensive care unit (ICU) patients with coronavirus disease 2019 (COVID-19) and severe hypoxaemia. We conducted pre-planned analyses of one-year mortality and health-related quality of life (HRQoL) in the Handling Oxygenation Targets in COVID-19 trial. The trial randomised 726 ICU patients with COVID-19 and hypoxaemia to partial pressure of arterial oxygen targets of 8 kPa (60 mmHg) versus 12 kPa (90 mmHg) during ICU stay up to 90 days, including readmissions. HRQoL was assessed using EuroQol visual analogue scale (EQ-VAS) and 5-level 5-dimension questionnaire (EQ-5D-5L). Outcomes were analysed in the intention-to-treat population. Non-survivors were assigned the worst possible score (zero), and multiple imputation was applied for missing EQ-VAS values. We obtained one-year vital status for 691/726 (95.2%) of patients and HRQoL data for 642/726 (88.4%). At one year, 117/348 (33.6%) of patients in the lower-oxygenation group had died compared to 134/343 (39.1%) in the higher-oxygenation group (adjusted risk ratio: 0.85; 98.6% confidence interval (CI) 0.66-1.09; p = 0.11). Median EQ-VAS was 50 (interquartile range, 0-80) versus 40 (0-75) (adjusted mean difference: 4.8; 98.6% CI  - 2.2 to 11.9; p = 0.09) and EQ-5D-5L index values were 0.61 (0-0.81) in the lower-oxygenation group versus 0.43 (0-0.79) (p = 0.20) in the higher-oxygenation group, respectively. Among adult ICU patients with COVID-19 and severe hypoxaemia, one-year mortality results were most compatible with benefit of the lower oxygenation target, which did not appear to result in more survivors with poor quality of life.