Relationship between Arterial Partial Oxygen Pressure Following Resuscitation from Cardiac Arrest and Mortality in Children
Background—Observational studies in adults have shown worse outcome associated with hyperoxia following 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) following cardiac arrest.
Methods and Results—Retrospective cohort study using Paediatric Intensive Care Audit Network (PICANet) database between 2003-2010 (n=122,521). Patients aged <16 years with documented cardiac arrest preceding PICU admission and arterial blood gas analysis taken within 1hr of PICU admission were included. The primary outcome measure was death within PICU. The relationship between oxygen status post-arrest and outcome was modeled using logistic regression, with non-linearities explored via multivariable fractional polynomials. Covariates included: age, sex, ethnicity, congenital heart disease, out-of-hospital arrest, year, PIM2 mortality risk and organ supportive therapies. Of 1875 patients, 735 (39%) died in PICU. Based on the first arterial gas, 207 (11%) patients had hyperoxia (PaO2 ≥300 mmHg) and 448 (24%) had hypoxia (PaO2 <60 mmHg). We found a significant non-linear relationship between PaO2 and PICU mortality. After covariate adjustment, risk of death increased sharply with increasing hypoxia (odds ratio 1.92 [95% CI 1.80 to 2.21] at PaO2 of 23 mmHg). There was also an association with increasing hyperoxia, although not as dramatic as that for hypoxia (odds ratio 1.25 [CI 1.17 to 1.37] at 600 mmHg). We observed an increasing mortality risk with advancing age, which was more pronounced in the presence of congenital heart disease.
Conclusions—Both severe hypoxia, and to a lesser extent, hyperoxia are associated with an increased risk of death after PICU admission following cardiac arrest.
- Received December 5, 2011.
- Accepted May 25, 2012.
- Copyright © 2012, American Heart Association, Inc. All rights reserved. Unauthorized use prohibited