Cardiac surgery, a right target for hyperoxia?

In perioperative cardiac surgery period, supra-physiological arterial oxygen partial pressures is common practice, although there is no clear evidence of any benefit. Smit et al. have shown that a "conservative" approach did not improve hemodynamics, decrease oxidative stress or myocardial tissue damage, but was not associated with major deleterious event either. Here, we outline major oxygen friend or foes properties, which may partly explain the study results, and place the clinical trial from Smit et al. in a global context.