Long-term mortality and health-related quality of life of lower versus higher oxygenation targets in ICU patients with severe hypoxaemia

Purpose: We assessed outcomes after 1 year of lower versus higher oxygenation targets in intensive care unit (ICU) patients with severe hypoxaemia. Methods: Pre-planned analyses evaluating 1-year mortality and health-related quality-of-life (HRQoL) outcomes in the previously published Handling Oxygenation Targets in the ICU trial which randomised 2928 adults with acute hypoxaemia to targets of arterial oxygen of 8 kPa or 12 kPa throughout the ICU stay up to 90 days. One-year all-cause mortality was assessed in the intention-to-treat population. HRQoL was assessed using EuroQol 5 dimensions 5 levels (EQ-5D-5L) questionnaire and EQ visual analogue scale score (EQ-VAS), and analyses were conducted in both survivors only and the intention-to-treat population with assignment of the worst scores to deceased patients. Results: We obtained 1-year vital status for 2887/2928 (98.6%), and HRQoL for 2600/2928 (88.8%) of the trial population. One year after randomisation, 707/1442 patients (49%) in the lower oxygenation group vs. 704/1445 (48.7%) in the higher oxygenation group had died (adjusted risk ratio 1.00; 95% confidence interval 0.93–1.08, p = 0.92). In total, 1189/1476 (80.4%) 1-year survivors participated in HRQoL interviews: median EQ-VAS scores were 65 (interquartile range 50–80) in the lower oxygenation group versus 67 (50–80) in the higher oxygenation group (p = 0.98). None of the five EQ-5D-5L dimensions differed between groups. Conclusion: Among adult ICU patients with severe hypoxaemia, a lower oxygenation target (8 kPa) did not improve survival or HRQoL at 1 year as compared to a higher oxygenation target (12 kPa)