Pre‐hospital central venous access in major trauma: balancing feasibility, safety and time to haemorrhage control

We read with interest the study by Pallavicini et al., which evaluated the feasibility, efficacy and safety of pre-hospital central venous access in patients with exsanguinating haemorrhage due to major trauma [1]. This work provides valuable insight into an advanced intervention performed by highly experienced pre-hospital physicians. However, several practical and conceptual points merit further consideration. While the authors show that pre-hospital trauma line insertion is feasible and associated with an acceptable complication rate, the study does not report whether this procedure affects pre-hospital timings. Although timings are provided for patients in whom a trauma line was attempted, no comparison is available with patients managed without central venous access. Scene time and total pre-hospital time are major determinants of survival in exsanguinating trauma [2]. Delays in transport to definitive haemorrhage control can offset any benefit from improved transfusion capability. The time required to prepare, perform and confirm a central line insertion, particularly in a complex pre-hospital environment, could have a significant impact on outcomes and deserves analysis. The subclavian approach, used in most cases, raises questions regarding optimal site selection. While the subclavian vein is used commonly for central venous access, it carries a risk of pneumothorax and uncompressible arterial injury, which may be difficult to detect during cardiac arrest or profound hypotension. In contrast, the femoral approach offers a compressible site, free from pleural complications and remains accessible during resuscitation. Femoral cannulation also allows simultaneous introduction of a resuscitative endovascular balloon occlusion of the aorta (REBOA) sheath when indicated, an increasingly recognised adjunct in refractory haemorrhagic shock [3]. The role of ultrasound guidance deserves further discussion. The device is now available widely in pre-hospital critical care systems and enables faster, safer and more reliable central venous access without increasing procedure time [4]. In the present study, ultrasound was used in only 6% of cases, which seems surprisingly low given its potential to reduce mechanical complications and improve first-pass success, even in challenging environments. Although the reported complication rate was low, this result must be interpreted in the context of an expert service. The London Air Ambulance physicians have extensive in-hospital experience with central venous catheterisation and benefit from a mature governance structure and procedural training. The reported median scene time of 34 min to perform assessment, vascular access and other advanced interventions also appears remarkably short, further supporting the influence of an experienced and highly co-ordinated team. Extrapolating these results to other systems may not be appropriate. In less experienced hands, the balance between procedural benefit and the risks of delay or complications could differ substantially. The authors rightly acknowledge this expert centre effect, a major limitation to external validity. Finally, from a human factors' perspective, there is a risk of cognitive fixation or tunnel vision during difficult or repeated attempts at central access. Cognitive biases such as anchoring and premature closure, often driven by time pressure in prehospital critical care, may lead clinicians to fixate on a single task, potentially delaying time-critical interventions or transport [5]. In extreme haemorrhagic shock, every minute spent away from haemorrhage control may worsen outcomes. The potential for task fixation underscores the need for strict procedural indications and team situational awareness. In summary, this study represents an important contribution to pre-hospital trauma care and shows that pre-hospital central venous access can be performed safely by expert teams. Nevertheless, its generalisability remains limited, and future work should clarify its impact on time metrics, site selection strategies and the role of ultrasound guidance. Above all, any procedural gain must be weighed against rapid transport to definitive haemorrhage control.