Oxygen targets and 6-month outcome after out of hospital cardiac arrest: a pre-planned sub-analysis of the targeted hypothermia versus targeted normothermia after Out-of-Hospital Cardiac Arrest (TTM2) trial

Chiara Robba, Gisela Lilja, Hans Friberg, Michelle S. Chew, Johan Unden, Josef Dankiewicz, Niklas Nielsen, Florian Ebner, Paolo Pelosi, Tobias Cronberg (Contributor), David Erlinge (Contributor), Helena Levin (Contributor), Per Nordberg (Contributor), Susann Ullén (Contributor), Karolina Palmér (Contributor), Ulla Britt Karlsson (Contributor), Simon Heissler (Contributor), Ameldina Ceric (Contributor), Zana Haxhija (Contributor), Joachim Düring (Contributor)Mattias Bergström (Contributor), Mattias Bohm (Contributor), Ingrid Didriksson (Contributor), Petrea Frid (Contributor), Katarina Heimburg (Contributor), Oscar Lundberg (Contributor), Stefan Olsson Hau (Contributor), Simon Schmidbauer (Contributor), Ola Borgquist (Contributor), Anna Bjärnroos (Contributor), Erik Blennow Nordström (Contributor), Irina Dragancea (Contributor), Thomas Kander (Contributor), Anna Lybeck (Contributor), Gustav Mattiasson (Contributor), Malin Rundgren (Contributor), Erik Westhall (Contributor), Martin Annborn (Contributor), Sara Andertun (Contributor), Jesper Johnsson (Contributor), Johan Unden (Contributor), Eelco F. M. Wijdicks (Contributor), TTM2 Trial collaborators

Research output: Contribution to journalArticlepeer-review

Abstract

Background: Optimal oxygen targets in patients resuscitated after cardiac arrest are uncertain. The primary aim of this study was to describe the values of partial pressure of oxygen values (PaO2) and the episodes of hypoxemia and hyperoxemia occurring within the first 72 h of mechanical ventilation in out of hospital cardiac arrest (OHCA) patients. The secondary aim was to evaluate the association of PaO2 with patients’ outcome. Methods: Preplanned secondary analysis of the targeted hypothermia versus targeted normothermia after OHCA (TTM2) trial. Arterial blood gases values were collected from randomization every 4 h for the first 32 h, and then, every 8 h until day 3. Hypoxemia was defined as PaO2 < 60 mmHg and severe hyperoxemia as PaO2 > 300 mmHg. Mortality and poor neurological outcome (defined according to modified Rankin scale) were collected at 6 months. Results: 1418 patients were included in the analysis. The mean age was 64 ± 14 years, and 292 patients (20.6%) were female. 24.9% of patients had at least one episode of hypoxemia, and 7.6% of patients had at least one episode of severe hyperoxemia. Both hypoxemia and hyperoxemia were independently associated with 6-month mortality, but not with poor neurological outcome. The best cutoff point associated with 6-month mortality for hypoxemia was 69 mmHg (Risk Ratio, RR = 1.009, 95% CI 0.93–1.09), and for hyperoxemia was 195 mmHg (RR = 1.006, 95% CI 0.95–1.06). The time exposure, i.e., the area under the curve (PaO2-AUC), for hyperoxemia was significantly associated with mortality (p = 0.003). Conclusions: In OHCA patients, both hypoxemia and hyperoxemia are associated with 6-months mortality, with an effect mediated by the timing exposure to high values of oxygen. Precise titration of oxygen levels should be considered in this group of patients. Trial registration: clinicaltrials.gov NCT02908308, Registered September 20, 2016.

Original languageEnglish
Article number323
Pages (from-to)1-13
JournalCritical Care
Volume26
DOIs
Publication statusPublished - 2022

Subject classification (UKÄ)

  • Cardiac and Cardiovascular Systems

Keywords

  • Cardiac arrest
  • Hyperoxemia
  • Hypoxemia
  • Mortality
  • Neurological outcome

Fingerprint

Dive into the research topics of 'Oxygen targets and 6-month outcome after out of hospital cardiac arrest: a pre-planned sub-analysis of the targeted hypothermia versus targeted normothermia after Out-of-Hospital Cardiac Arrest (TTM2) trial'. Together they form a unique fingerprint.

Cite this