Evaluating the Success Rate of Distal Femur Intraosseous Access Attempts in Pediatric Patients in the Prehospital Setting: A Retrospective Analysis.

Objectives: Although the proximal tibia is a common site for intraosseous (IO) line placement in pediatric patients, previously published data indicate high malposition rates in infants and children at this location. Although distal femur IO lines generally demonstrate higher flow rates than those at the proximal tibia, to date, there have been no published studies assessing distal femur IO access in pediatric patients. Thus, we aimed to compare the success rates of pediatric IO line insertion attempts between the proximal tibia and the distal femur in a prehospital setting.

Methods: We conducted a retrospective chart review of prehospital pediatric patients who underwent at least one IO line placement attempt by Palm Beach County Fire Rescue from May 2015 to January 2024. We excluded records lacking specific documentation of IO attempt location. We compared the unadjusted success rates of distal femur to proximal tibia, and we also compared success rates after propensity score matching and multivariable logistic regression. Secondarily, we assessed the prehospital complication rate of the IO lines at each anatomical site.

Results: We identified 163 pediatric patients who had an IO attempt and were eligible for analysis. Median age was 1.9 years (IQR: 0.46 to 4.2 years). Among those 163 patients, there were 234 vascular access attempts, including 82 IO attempts at the distal femur and 72 at the proximal tibia. The unadjusted success rate of distal femur attempts was 89.0%, compared to 84.7% for proximal tibia attempts, a difference of 4.3% (95% CI -6.4 to 15.0%). After propensity score matching, we found an adjusted odds ratio of 2.0 (95% CI 0.66 to 6.8), favoring the distal femur for successful placement. Prehospital complication rates were similar for distal femur (5.5%) and proximal tibia (4.9%).

Conclusions: This retrospective analysis of pediatric patients in a prehospital setting suggests that IO line placement at the distal femur might offer a marginally higher success rate compared to the proximal tibia. Despite not reaching statistical significance, these findings support the consideration of distal femur as a viable option for IO placement in the pediatric population.