# Rationale, development and feasibility of a national prehospital transfusion registry

## TL;DR

This study shows it's feasible to link prehospital and hospital records for patients receiving blood transfusions outside hospitals, supporting the creation of a national registry.

## Contribution

The paper demonstrates the feasibility of a national prehospital transfusion registry through successful data linkage between ambulance and hospital systems.

## Key findings

- 91.1% of prehospital and hospital records were successfully linked using indirect identifiers.
- Six patients died before transport, but most transported patients had their records successfully matched.
- The study supports the potential for a national registry to improve trauma care.

## Abstract

Out-of-hospital blood transfusion (OHBT) is an emerging practice for the management of hemorrhagic shock following trauma. The Canadian Prehospital and Transport Transfusion (CAN-PATT) network aims to standardize OHBT practices and assess the feasibility of linking out-of-hospital care with in-hospital outcomes through a national registry.

This was a retrospective cohort study of patients who received OHBT through an air ambulance program between September 2021 and July 2024 and were transported to one of two regional trauma centers. Prehospital data from the air ambulance database were linked using indirect identifiers to hospital data from the trauma registries and manually reviewed charts. The primary outcome was the percentage of prehospital and in-hospital records that could be successfully linked. Continuous variables were summarized as means/standard deviations or medians/interquartile ranges, and categorical variables as counts and frequencies.

There were 96 patients who received an OHBT during the study period; 90 were transported to a participating regional trauma center and 6 died prior to transport. Of the 90 patients, 82 (91 %) were successfully linked (Site 1: 36/39; Site 2: 46/51) between the air ambulance database and hospital trauma registries using indirect identifiers (age, sex, date and time of transport).

This study demonstrates the feasibility of linking prehospital and in-hospital records for OHBT recipients, achieving a 91.1 % linkage rate. Future work should aim to incorporate trip numbers and missing variables into hospital registries to support the establishment of a national OHBT registry to enhance prehospital trauma care.