Objective
Determine whether the SpO2/FiO2 ratio correlates with the PaO2/FiO2 ratio in burned children with smoke inhalation injury (SII), with the goal of understanding if the SpO2/FiO2 ratio can serve as a surrogate for the PaO2/FiO2 ratio for the diagnosis of acute respiratory distress syndrome (ARDS).
Design
Retrospective chart review.
Setting
Shriners Hospitals for Children - Galveston.
Patients
All burned children with SII who were admitted from 1996 to 2014 and had simultaneously obtained SpO2, FiO2, and PaO2 measurements.
Interventions
None.
Measurements and Main Results
Two hundred seventy-three patients (63% male, 8 ± 5 years, 53 ± 24% total body surface area burns) were analyzed. SpO2/FiO2 ratios were divided into 4 subgroups based on SpO2 values (≤ 100%, ≤ 98%, ≤ 95%, ≤ 92%). Significance was accepted at r2 > 0.81. The r2 (number of matches) was 0.66 (23,072) for ≤ 100%, 0.87 (18,932) for ≤ 98%, 0.89 (7,056) for ≤ 95%, and 0.93 (4,229) for ≤ 92%. In the subgroup of patients who developed ARDS, r2 was 0.65 (8,357) for ≤ 100%, 0.89 (7,578) for ≤ 98%, 0.89 (4,115) for ≤ 95%, and 0.91 (2,288) ≤ 92%.
Conclusions
PaO2/FiO2 and SpO2/FiO2 strongly correlate in burned children with SII, with a SpO2 of <92% providing the strongest correlation. Thus, SpO2/FiO2 ratio may be able to serve as surrogate for PaO2/FiO2, especially when titrating FiO2 to achieve a SpO2 of 90–95% (i.e., in the ARDS range).