Injury. 2019 Feb;50:226-234

# What is the impact of prehospital blood product administration for patients with catastrophic haemorrhage: an integrative review.

Shand S, Curtis K, Dinh M, Burns B

INTRODUCTION: Catastrophic haemorrhage is recognised as the leading cause of preventable death in trauma and is also prevalent in medical and other surgical aetiology. Prehospital blood product transfusion is increasingly available for both military and civilian emergency teams. Hospitals have well-established massive transfusion protocols for the resuscitation of this patient group, however the use and impact in the prehospital field is less understood.

AIM: To identify and evaluate the current knowledge surrounding prehospital blood product administration for patients with catastrophic haemorrhage.

METHODS: The integrative review method included systematic searching of online databases Medline, EMBASE, SCOPUS and CINAHL alongside hand-searching for primary research articles published prior to 19 November 2018. Papers were included if the population studied patients with catastrophic haemorrhage who received prehospital transfusion of blood products. The level of evidence and quality was evaluated using the NHMRC hierarchy of evidence. All identified full text articles were reviewed by all authors.

RESULTS: Twenty-two papers were included in the final analysis, including both civilian (16) and military (6) practice. The earliest publication for prehospital transfusion was 1999, with increasing prevalence in recent years. Findings were extracted and into two main categories; (1) transfusion processes included team staffing, product selection, and criteria for transfusion and (2) transfusion outcomes; transfusion safety, haemoglobin, hospital intervention and mortality.

DISCUSSION: The level of evidence specific to prehospital blood product transfusion is low, with predominantly retrospective methods and rarely sufficient sample sizes to reach statistical significance. Prehospital research is challenged by clinical and logistical variability preventing accurate cohortmatching, sample sizes and inconsistent data collection. Evaluation of prehospital transfusion in isolation is also particularly problematic as multiple factors and developments in clinical practice affect patient outcomes and all samples were subject to survival bias. Conclusion The volume and strength of the available evidence prevents accurate evaluation of the intervention and definitive practice recommendations however prehospital transfusion is shown to be logistically achievable and without serious incident. The reviewed evidence broadly supports the translation of recent in-hospital studies, such as PROMTT and PROPPR. Further research specific to prehospital practice is required to guide the development of evidence-based protocols.