Current management principles of hemorrhagic shock after trauma emphasize earlier transfusion therapy to prevent dilution of clotting factors and correct coagulopathy. London's Air Ambulance (LAA) was the first UK civilian prehospital service to routinely offer prehospital red blood cell (RBC) transfusion (phRTx). We investigated the effect of phRTx on mortality.
Retrospective trauma database study comparing mortality before implementation with after implementation of phRTx in exsanguinating trauma patients. Univariate logistic regression was performed for the unadjusted association between phRTx and mortality was performed, and multiple logistic regression adjusting for potential confounders.
We identified 623 subjects with suspected major hemorrhage. We excluded 84 (13.5%) patients due to missing data on survival status. Overall 187 (62.3%) patients died in the before phRTx period and 143 (59.8%) died in the after phRTx group. There was no significant improvement in overall survival after the introduction of phRTx (P = 0.554). Examination of prehospital mortality demonstrated 126 deaths in the pre-phRTx group (42.2%) and 66 deaths in the RBC administered group (27.6%). There was a significant reduction in prehospital mortality in the group who received RBC (P < 0.001).
phRTx was associated with increased survival to hospital, but not overall survival. The “delay death” effect of phRTx carries an impetus to further develop inhospital strategies to improve survival in severely bleeding patients.
*London's Air Ambulance, Barts Health NHS Trust, London, United Kingdom
†The Norwegian Air Ambulance Foundation, Drøbak, Norway
‡Faculty of Health Sciences, University of Stavanger, Stavanger, Norway
§Barts Health NHS Trust, London, United Kingdom
||Blizard Institute, Queen Mary, University of London, London, United Kingdom
¶NHS Blood and Transplant, London, United Kingdom
Address reprint requests to Marius Rehn, PhD, London's Air Ambulance, Royal London Hospital, Whitechapel Road, London E1 1BB, United Kingdom. E-mail: firstname.lastname@example.org
Received 3 January, 2018
Revised 2 February, 2018
Accepted 11 April, 2018
Ethics approval and consent to participate: The project protocol was considered by the LAA research and development committee. It met local criteria for, and was registered as, a trust service evaluation project (ID 6191). No additional interventions were carried out and the study recorded only the frequency of events in normal practice with a view to service improvement. Ethical approval was therefore not sought. Consent for publication of individual person's data not applicable.
Authors’ contributions: All authors designed the study, collecting data and contributed in writing the manuscript; MR, SE, and JR analyzed the data. All authors read and approved the final manuscript.
The Norwegian Air Ambulance Foundation funded MR and JR expenses and publishing costs, but had no role in manuscript writing, study design, collection, analysis, or interpretation of data.
The authors report no conflicts of interest.