‘Watch where you’re sticking that!’: the ability of paramedics to accurately locate correct anatomical sites for intraosseous needle insertion
Previous studies report high success rates of intraosseous (IO) access, with unsuccessful insertion attributed to incorrect site placement and failure to adhere to anatomical landmarks. Berger et al (2023) conducted a prospective observational study assessing the ability of 30 paramedics based in Pennsylvania (USA) to identify the correct locations for both proximal humeral and proximal tibial IO insertion sites. All participants had been trained in IO insertion, with 57% having completed ten or more IO insertions clinically. Although a high percentage of participating paramedics verbally identify the correct location for IO placement, fewer were able to locate the correct insertion site on a human volunteer.
Participants’ insertion site was compared with the physician-identified ‘correct’ site, via a system of overlay transfers, and distances from the ‘correct’ site were recorded to the nearest 0.5cm. While 26 paramedics (90%) correctly identified both the proximal humerus and proximal tibia, 70% of participants selected a site >2cm from the physician-identified site.
In proximal humeral head insertion, only 37% internally rotated the humerus prior to placement, achieving an average distance from the landmark of 3.32cm (standard deviation [SD] 2.41cm) compared with 6.07cm (SD 2.32cm) in non-rotated arms placements. This result is statistically significant (p<0.01).
The authors recognise the limitations of this observational study, it being a non-randomised small sample group (30 paramedics attending a State-wide EMS conference over 2 separate days). The participants’ competence and previous IO success rate were not considered, nor was any comparison made between participants who had received cadaver vs mannikin practice. The ‘correct’ insertion sites were identified by a single physician and were not verified with imaging and two different, but anatomically similar, human volunteers. The direction and/or angle of insertion was not recorded data.
The authors recommend frequent hands-on refresher training to maintain competency in identifying correct IO insertion sites.
It’s bound (non-invasively) to be a pelvic injury… or is it?
Destabilisation of the pelvic ring due to trauma is associated with high mortality rates due to severe haemorrhage; however, survival has improved significantly due to the availability of pelvic binders and developments in on-site interventions. Prehospital management of a pelvic ring injury should see the application of a non-invasive pelvic binder device (NIPBD), in order to prevent exsanguination—but are we as good as we should be?
This retrospective cohort study reviewed all patients with a pelvic injury transported by the helicopter emergency medical services (HEMS) to a level-one trauma centre in the Netherlands between 2012 and 2020. The HEMS comprises a specialised physician (trauma surgeon or anaesthesiologist) and a paramedic, and is dispatched in addition to standard ambulance care.
The research team interrogated the national trauma registry to identify all patients with a pelvic ring injury. Radiological data were used to classify the pelvic fracture according to the Young & Burgess system. This system categorises pelvic ring fractures based on the vector of traumatic energy.
The team identified 634 patients with pelvic injuries, of whom 392 (61.8%) had pelvic ring injuries and 143 (22.6%) had unstable pelvic ring injuries. Pelvic injury was suspected by HEMS personnel in 120 (30.6%) of the pelvic ring injuries and in 67 (46.9%) of the unstable pelvic ring injuries. The specificity for correct diagnosis of a stable pelvic injury was 78.7% (95% CI: 73.1–83.6 and for distinguishing unstable or stable pelvic injuries was 67.1% (95 CI% 62.2–71.7). An NIPBD was applied in 108 (27.6%) of the patients with a pelvic ring injury and in 63 (44.1%) of patients with an unstable pelvic ring injury. These rates are in keeping with other studies and reflect the challenges of identifying pelvic ring injuries in the field.