An observational study of pre-hospital central venous access for patients with haemorrhagic shock due to major trauma.

INTRODUCTION Exsanguinating haemorrhagic shock due to major trauma is associated with high mortality. Rapid intravenous volume replacement with blood products is a crucial element of early treatment. When peripheral intravenous access cannot be obtained, pre-hospital placement of a large-calibre central venous catheter, known as a trauma line, can be a life-saving alternative. METHODS This was a retrospective cohort study to evaluate the feasibility, efficacy and safety profile of inserting a 14-Fr trauma line in patients with exsanguinating haemorrhage due to major trauma in the pre-hospital setting. Success rates, outcomes and complications of trauma line insertion were determined by cross-referencing pre-hospital patient care records with emergency department notes, operating notes and post-mortem findings. RESULTS Between 1 January 2019 and 31 July 2023, London's Air Ambulance attended 8104 patients. Trauma line insertion was attempted in 346 (4%) patients with success in 276 (80%). Successful trauma line insertion was associated with significantly greater transfusion of pre-hospital blood products compared with those in whom insertion was unsuccessful (median (IQR [range]) 4 (2-6 [0-12]) vs. 2 (0-4 [0-8]) units, respectively; p < 0.001). Survival to presentation to the emergency department was higher after successful trauma line insertion (149/279 (54%) vs. 25/70 (36%); p = 0.006). There were 184 (53%) patients transported to hospital. Complications in this group were reported in 8 (4%) patients: malpositioned trauma line (n = 3); vascular injuries (n = 2); iatrogenic pneumothorax (n = 2); and positive trauma line tip culture (n = 1). DISCUSSION In patients with exsanguinating haemorrhage who are in severe shock or traumatic cardiac arrest, pre-hospital trauma line insertion is feasible and associated with an acceptable risk of procedural complications. Trauma lines enable the delivery of a greater volume of blood products in the pre-hospital setting, which may be associated with increased pre-hospital survival.