Oxygenation targets in ICU patients with COVID-19: a post-hoc sub-group analysis of the HOT-ICU trial.

Rasmussen, Bodil S; Klitgaard, Thomas L; Perner, Anders; Brand, Björn A; Hildebrandt, Thomas; Siegemund, Martin; Hollinger, Alexa; Aagaard, Søren R; Bestle, Morten H; Marcussen, Klaus V; Brøchner, Anne C; Sølling, Christoffer G; Poulsen, Lone M; Laake, Jon H; Aslam, Tayyba N; Bäcklund, Minna; Okkonen, Marjatta; Morgan, Matthew; Sharman, Mike; Lange, Theis; Wetterslev, Jørn; Schjørring, Olav L

BACKGROUND Supplemental oxygen is the key intervention for severe and critical COVID-19 patients. With the unstable supplies of oxygen in many countries it is important to define the lowest safe dosage. METHODS In spring 2020, 110 COVID-19 patients were enrolled as part of the Handling Oxygenation Targets in the ICU trial (HOT-ICU). Patients were allocated within 12 hours of ICU admission. Oxygen therapy was titrated to a partial pressure of arterial oxygen (PaO2 ) of 8 kPa (lower oxygenation group) or a PaO2 of 12 kPa (higher oxygenation group) during ICU stay up to 90 days. We report key outcomes at 90 days for the sub-group of COVID-19 patients. RESULTS At 90 days, 22 of 54 patients (40.7%) in the lower oxygenation group and 23 of 55 patients (41.8%) in the higher oxygenation group had died (adjusted risk ratio: 0.87; 95% confidence interval, 0.58 - 1.32). Percentage of days alive without life support was significantly higher in the lower oxygenation group (p=0.03). Numbers of severe ischemic events were low with no difference between the two groups. Proning and inhaled vasodilators were used more frequently, and the positive end-expiratory pressure was higher in the higher oxygenation group. Tests for interactions with the results of the remaining HOT-ICU population were insignificant. CONCLUSIONS Targeting a PaO2 of 8 kPa may be beneficial in ICU patients with COVID-19. These results come with uncertainty due to the low number of patients in this unplanned sub-group analysis, and insignificant tests for interaction with the main HOT-ICU trial.