Fig. 3

Arterial partial pressure of oxygen (PaO₂) mortality risk profile. In this Cox regression, PaO₂ was modeled with a fractional polynomial (FP) of second degree FP [0–1], and included the following covariates: TTM2 randomization group, tympanic temperature at admission, age (years), gender, Charlson comorbidity index, cardiac arrest witnessed, time to return to spontaneous circulation, ROSC (min), bystander performed cardiopulmonary resuscitation, CPR, shockable rhythm, cardiac arrest location (home, public place, other), shock diagnosis on admission, ST-Elevated myocardial infarction (STEMI) diagnosis on admission, respiratory rate (breath/min), positive end-expiratory pressure, arterial partial pressure of carbon dioxide (PaCO₂) (mmHg), pHa, and Base excess (mEq/L), Driving pressure (cmH₂0), and mechanical power (J/min). Along the PaO₂ continuum, values before and after its median (108.7 mmHg and used as reference—see vertical line in red) were statistically associated with mortality if the 95% confidence interval (CI) did not cover the y-line of 1 (horizontal line in red)