The PhD defence will take place
Wednesday, May 25th, 2022 at 13:00
Auditoriet, Medicinerhuset, Aalborg Universitetshospital
Hobrovej 18-22, 9000 Aalborg

After the defence there will be held a reception. All are welcome.

Supervisors

Professor Bodil Steen Rasmussen, MD, PhD
Department of Anaesthesia and Intensive Care, Aalborg University Hospital
Department of Clinical Medicine, Aalborg University

Associate professor Olav Lilleholt Schjørring, MD, PhD
Department of Anaesthesia and Intensive Care, Aalborg University Hospital
Department of Clinical Medicine, Aalborg University

Assessment Committee

Associate professor Helle Damgaard Zacho (Chair)
Department of Nuclear Medicine and Clinical Cancer Research Centre, Aalborg University Hospital
Department of Clinical Medicine, Aalborg University

Professor Manu Shankar-Hari
King’s College and St. Thomas’ Hospital, London

Professor Jacob Steinmetz
Danish Air Ambulance & Aarhus University, Aarhus
Department of Clinical Medicine, Copenhagen University

About the PhD thesis

Oxygen is the most prescribed medical drug world-wide and essential for the proper functioning of the human body. Both too low and too high levels of oxygen has been associated with increased mortality in critically ill patients.

Study I was a multi-centre, international clinical trial, randomising patients with acute hypoxaemic respiratory failure admitted to the intensive care unit (ICU), to either a lower or a higher oxygenation target: the ‘Handling Oxygenation Targets in the ICU’ (HOT-ICU) trial. In total, 2928 patients were included. No significant differences in all-cause mortality, need for life-support, length of stay in hospital, or number of serious adverse events were found.

Study II evaluated the mortality effect in the HOT-ICU trial using Bayesian statistical methods. Large mortality effects were unlikely, but a higher oxygenation target, as compared to a lower, was probably beneficial in patients with increasing levels of circulatory failure at baseline in the HOT-ICU population.

Study III was an updated systematic Cochrane review on higher versus lower oxygenation strategies in the ICU. Identified trials were highly diverse in terms of included patients, duration of intervention, and definitions of such. No differences were found for mortality, number of serious adverse events or lung injuries, or in self-reported quality of life. However, the certainty of evidence was low or very low.

The findings of the thesis suggest that when targeting ICU patients’ oxygenation within the normal range, oxygen therapy does not contribute to increased risk of death or serious adverse events. Yet, the exact effect of targeted oxygen therapy is still uncertain and may differ within specific patient subgroups.