Interpretation of Findings
This study contributes to the evidence evaluating the population-driven need for acquisition of REBOA at Canadian trauma centres. The majority of studies on the efficacy of REBOA in the management of massive hemorrhage from infra-diaphragmatic injury are from other countries, including the USA and Japan,16, 23–27 in which REBOA is used more commonly; however, the trauma populations, resources, and patterns of injury are vastly different internationally.
In our study, we identified that 14 patients over a three-year period at our institution would have met criteria for use of REBOA during resuscitation. Those that met criteria represented a severely injured group of patients and constituted 2.2% of the TTAs and 1.1% of all trauma consults. This can be extrapolated to indicate that REBOA may be utilized in four to five patients per year at our institution. Our findings are consistent with the results of a recent 2021 publication that conducted a similar needs assessment for REBOA at multiple major trauma centres in Edmonton, Canada35. This study also found that 1.1% of the study population met eligibility criteria for deployment of REBOA. Although a seemingly small number, this may be clinically significant given that trauma patients are often young, previously healthy individuals with the physiologic reserve to survive this procedure. Additionally, these patients stand to gain many potential high-quality years of life.
In comparison, our institution performed between three to six resuscitative thoracotomies per year (1.0% of all trauma consults) during the study time period. Similar to REBOA, RT is a procedure that is performed rarely and requires the need for subsequent immediate definitive management; however, in the setting of infra-diaphragmatic hemorrhage, RT is substantially more invasive and only attempted in patients that have already progressed to cardiac arrest.
Our data indicate that the most common indication for the use of REBOA in our trauma population was for patients that had sustained blunt trauma. The most common mechanism of injury in the REBOA candidates was being a pedestrian struck by a vehicle. This is consistent with Canadian statistics that show the majority of trauma in our country is secondary to blunt trauma. In comparison, the United States has a much higher rate of penetrating trauma.32–34 Of note, the percentage of cases that met candidacy criteria in our study is greater than that found in a 2019 study at a US trauma centre that used similar inclusion criteria. The authors found that 0.6% of the trauma patients seen in their ED per year may have potentially benefitted from REBOA, but over half (53%) of which had sustained a penetrating traumatic injury. 20
The main limitation of this study is that, as a retrospective chart review, identification of cases that meet REBOA candidacy does not necessarily reflect that the intervention would have changed the patient outcome. It is important to note that of the 14 Likely Candidates, only three died from their injuries and 11 survived without REBOA. Furthermore, only eight out of the 14 Likely Candidates went directly to the OR or IR suite for attempted embolization. The other six patients did not end up requiring surgery or embolization. However, this reflects the reality that the physician’s decision to place REBOA is made early during patient assessment and sometimes without definitive imaging. As with any intervention, its availability provides an option to the care provider that can be employed on a case-by-cases basis according to the physician’s clinical judgement that it will improve the outcome of the patient.
It is also notable that the mean SBP on ED arrival for both the Potential and Likely Candidates was greater than 100mmHg. However, a patient’s clinical status cannot be reflected by a single value as this is only representative of a moment in their post-injury course. In contrast to these blood pressures, the mean number of units of blood product transfused in the Likely Candidates was 5.5 in the first hour and 39.2 total in the first 24 hours. This meets criteria for massive transfusion at our institution and is indicative of the critical condition of these patients.
One of the strengths of our methods is how we screened for potential REBOA candidates. Other studies have defined the indication for REBOA using ICD-9 or 10 codes20 or ISS35; however, TTA criteria are more clinically relevant as they are used in real time by physicians during active management of trauma cases. Although there might not have been a change in the outcome for all of the Candidates identified in our study, this is more representative of how decisions about interventions are made by physicians in the moment, without a retrospective lens.