A Standardized Formulary to Reduce Pediatric Medication Dosing Errors: A Mixed Methods Study.

Objective: We hypothesized that implementation of a Medical Control Guideline (MCG) with a standardized formulary (fixed medication concentrations) and pre-calculated medication dosages in a large emergency medical services (EMS) system would reduce pediatric dosing errors. To assess the effectiveness of the standardized formulary to reduce errors, we chose to evaluate midazolam administration for seizures, because it is the most frequently dosed medication by EMS for children, and seizures are a time-sensitive condition. The objective of this study was to compare: 1) frequency of midazolam dosing errors during the field treatment of pediatric seizures and 2) paramedic anxiety and confidence in dosing midazolam for pediatric seizures, before and after implementation of the MCG. Methods: In this mixed-methods study, we utilized the Los Angeles County EMS data registry to identify pediatric patients ≤14 years-old treated with midazolam for seizure. We defined a dosing error as outside the dose directed by the color code on the length-based resuscitation tape, or ±20% the weight-based midazolam dose when color code was absent. We compared dosing errors during a two-year period before and after implementation of the MCG with the standardized formulary in February 2017. We surveyed paramedics to assess their level of anxiety and confidence in dosing midazolam and conducted semi-structured interviews with 20 respondents to further explore its impact on paramedic practice. Results: There were 80 dosing errors in 569 patients treated post-formulary (14.1%) compared with 92 dosing errors in 497 patients treated pre-formulary (18.5%), risk difference -4.5% (95% CI -8.9 to 0.0), p = 0.049. Among 304 paramedic survey respondents who had experience with the formulary, anxiety decreased (p < 0.001) and confidence increased (p < 0.001) post-formulary. Paramedics expressed the challenges of pediatric calls, the benefits of the MCG with the standardized formulary, and the ongoing challenges of pediatric medication dosing. Benefits included simplifying paramedic tasks, increasing paramedic self-efficacy, facilitating provider communication, and improving patient care. Conclusion: Implementation of a MCG with standardized formulary and pre-calculated medication dosing by weight reduced pediatric medication dosing errors and increased paramedic confidence in pediatric medication dosing. It may have the potential to facilitate patient care through improved communications and task simplification.