Oxygen Targets in Comatose Survivors of Cardiac Arrest

Abstract

BACKGROUNDThe appropriate oxygenation target for mechanical ventilation in comatose survivors of out-of-hospital cardiac arrest is unknown. METHODSIn this randomized trial with a 2-by-2 factorial design, we randomly assigned comatose adults with out-of-hospital cardiac arrest in a 1:1 ratio to either a restrictive oxygen target of a partial pressure of arterial oxygen (Pao 2 ) of 9 to 10 kPa (68 to 75 mm Hg) or a liberal oxygen target of a Pao 2 of 13 to 14 kPa (98 to 105 mm Hg); patients were also assigned to one of two blood-pressure targets (reported separately). The primary outcome was a composite of death from any cause or hospital discharge with severe disability or coma (Cerebral Performance Category [CPC] of 3 or 4; categories range from 1 to 5, with higher values indicating more severe disability), whichever occurred first within 90 days after randomization. Secondary outcomes were neuron-specific enolase levels at 48 hours, death from any cause, the score on the Montreal Cognitive Assessment (ranging from 0 to 30, with higher scores indicating better cognitive ability), the score on the modified Rankin scale (ranging from 0 to 6, with higher scores indicating greater disability), and the CPC at 90 days. RESULTSA total of 789 patients underwent randomization. A primary-outcome event occurred in 126 of 394 patients (32.0%) in the restrictive-target group and in 134 of 395 patients (33.9%) in the liberal-target group (hazard ratio, 0.95; 95% confidence interval, 0.75 to 1.21; P = 0.69). At 90 days, death had occurred in 113 patients (28.7%) in the restrictive-target group and in 123 (31.1%) in the liberal-target group. On the CPC, the median category was 1 in the two groups; on the modified Rankin scale, the median score was 2 in the restrictive-target group and 1 in the liberaltarget group; and on the Montreal Cognitive Assessment, the median score was 27 in the two groups. At 48 hours, the median neuron-specific enolase level was 17 μg per liter in the restrictive-target group and 18 μg per liter in the liberaltarget group. The incidence of adverse events was similar in the two groups. CONCLUSIONSTargeting of a restrictive or liberal oxygenation strategy in comatose patients after resuscitation for cardiac arrest resulted in a similar incidence of death or severe disability or coma. (Funded by the Novo Nordisk Foundation; BOX ClinicalTrials .gov number, NCT03141099.

Fokus Beatmung, Sauerstofftherapie und Weaning 2021/2022

“…Schmidt H, Kjaergaard J, Hassager C et al (2022) Oxygen targets in comatose survivors of cardiac arrest. N Engl J Med 387(16):1467–1476 [ 9 ]…”

“…In der Studie von Schmidt et al. sollte daher untersucht werden, ob eine restriktive Sauerstoffstrategie für Patienten nach einem Herz-Kreislauf-Stillstand von Vorteil wäre [ 9 ].…”

“…Zusammenfassend hatte bei Patienten dieser Studie mit prähospitalem Herz-Kreislauf-Stillstand ein p a O 2 von 9–10 kPa (68–75 mm Hg) im Vergleich zu einem p a O 2 von 13–14 kPa (98–105 mm Hg) keinen Einfluss auf die Sterblichkeit oder die Wahrscheinlichkeit einer Entlassung aus dem Krankenhaus mit einem schlechten neurologischen Ergebnis [ 9 ].…”

Hyperoxia during venoarterial ECMO: Culprit or co-variate? A comment from the BLENDER investigators

“…The clinical significance of hyperoxia in critically ill patients remains unclear [ 1 – 3 ]. Oxidative stress has been linked to the progression of numerous disease states.…”

“…Exposure to supraphysiological partial pressures of oxygen can induce oxidative stress [ 4 ]. Interpretation of observational studies and clinical trials is exceedingly challenging due to heterogeneity brought about by patient and disease factors [ 3 , 5 ].…”