Observational studies in adults have shown a worse outcome associated with
hyperoxia after
resuscitation from
cardiac arrest. Extrapolating from adult data, current pediatric
resuscitation guidelines recommend avoiding
hyperoxia. We investigated the relationship between arterial partial
oxygen pressure and survival in patients admitted to the pediatric intensive care unit (PICU) after
cardiac arrest.
METHODS AND RESULTS: We conducted a retrospective cohort study using the Pediatric
Intensive Care Audit Network (PICANet) database between 2003 and 2010 (n=122,521). Patients aged <16 years with documented
cardiac arrest preceding PICU admission and arterial blood gas analysis taken within 1 hour of PICU admission were included. The primary outcome measure was death within the PICU. The relationship between postarrest
oxygen status and outcome was modeled with logistic regression, with nonlinearities explored via multivariable fractional polynomials. Covariates included age, sex, ethnicity,
congenital heart disease, out-of-hospital arrest, year, Pediatric Index of Mortality-2 (PIM2) mortality risk, and organ supportive
therapies. Of 1875 patients, 735 (39%) died in PICU. Based on the first arterial gas, 207 patients (11%) had
hyperoxia (Pa(O)(2) ≥300 mm Hg) and 448 (24%) had
hypoxia (Pa(O)(2) <60 mm Hg). We found a significant nonlinear relationship between Pa(O)(2) and PICU mortality. After covariate adjustment, risk of death increased sharply with increasing
hypoxia (odds ratio, 1.92; 95% confidence interval, 1.80-2.21 at Pa(O)(2) of 23 mm Hg). There was also an association with increasing
hyperoxia, although not as dramatic as that for
hypoxia (odds ratio, 1.25; 95% confidence interval, 1.17-1.37 at 600 mm Hg). We observed an increasing mortality risk with advancing age, which was more pronounced in the presence of
congenital heart disease.
CONCLUSIONS: