To determine whether the association between hyperoxia and increased risk-adjusted mortality in adult intensive care patients is also observed in a pediatric intensive care population.Design:
Single-center retrospective analysis of admissions to ICU over a 5-year period commencing January 1, 2012, examining the relationship between PaO2 measured within the first hour of admission and risk-adjusted mortality. Standardized mortality rates were calculated using the Pediatric Index of Mortality-3, and patients were grouped into 50 mm Hg (6.67 kPa) PaO2 bands to assess the relationship between initial PaO2 and risk-adjusted mortality.Setting:
Tertiary PICU with 17 beds and 1,100 annual admissions located in metropolitan Sydney, Australia.Patients:
A total of 1,447 patients 0–18 years old with PaO2 recorded at admission to the ICU.Interventions:
None.Measurements and Main Results:
There were 5,176 patients admitted to the ICU during the study period and 1,447 (28%) with PaO2 recorded at admission. A U-shaped relationship between raw mortality and admission PaO2 was observed, with lowest mortality (2.3% and 2.6%, respectively) observed in the 101–150 (13.5–20.0 kPa) and 151–200 mm Hg (20.1–26.7 kPa) bands and the highest mortality observed in patients with PaO2 less than 50 mm Hg (6.67 kPa) with mortality of 5.3%, or greater than 350 mm Hg (46.7 kPa) with mortality of 18.2%. Hyperoxia at admission was associated with an increase in risk-adjusted mortality, with polynomial regression indicating a strong correlation between PaO2 band and risk-adjusted outcome (r2 = 0.845). When included in a multivariate model that included the Pediatric Index of Mortality-3 variables, the odds ratio for hyperoxia (defined as PaO2 > 250 mm Hg [33.3 kPa]) predicting death was 2.66 (p = 0.047).Conclusions:
In this single-center study, hyperoxia at admission to the PICU was highly correlated with increased risk-adjusted mortality. Further investigation of these observations in a large multicenter cohort is warranted.