A UK-wide multicentre study has shown no correlation between time to embolization and 30-day survival in patients presenting with splenic injury to a major trauma centre (MTC) in-hours or out-of-hours.
Led by Paul Jenkins (University Hospital Plymouth NHS Trust, Plymouth, UK) and published in the journal CardioVascular and Interventional Radiology (CVIR), the research team sought to determine whether time of arrival at a MTC influences embolization rate, time to embolization, embolization failure and 30-day survival in adult trauma patients.
Jenkins and colleagues note that splenic artery embolization (SAE) has an increasing role in modern trauma care. Backed by multiple studies, SAE has demonstrated higher rates of splenic preservation and reduced need for surgery.
“It is essential that SAE is delivered in a timely fashion, particularly in patients with active bleeding or vascular injury,” Jenkins et al state, which, suggests that prompt intervention achieves optimal outcomes. However, they continue that this concept of timeliness is “nuanced and depends not only on imaging features but also on haemodynamic stability”, raising the question of whether in certain groups the time to embolization may not be critical to the immediate management but prevention of future deterioration.
In their investigation, the authors analysed data for adults over the age of 18 years admitted to a MTC who were recorded in the UK Trauma Audit and Research Network database between January 2017 and December 2021. ‘In-hours’ was defined as Monday to Friday between 9am–5pm; all other times were defined as ‘out-of-hours’. Jenkins and colleagues add that descriptive and regression analyses assessed factors associated with time to embolization and 30-day survival, and the relationship between outcomes.
Among 2,560 patients with splenic injury directed to a MTC, 184 (7.2%) underwent embolization within 24 hours of admission. Of these, 79% were male with a median age of 42 years. Embolization within 24 hours occurred in 48 of 600 (8%) of patients admitted in-hours versus 136/1,960 (6.9%) admitted out-of-hours.
Embolization failure rate was similar between groups (6.3% in-hours vs. 9.6% out-of-hours). American Association for the Surgery of Trauma (AAST) grade and probability of survival were similar across groups. Median time to embolization was 159 minutes (95% confidence interval [CI]: 142–213) in-hours and 238 minutes (95% CI: 210–288) out-of-hours.
The authors state that, after adjustment, out-of-hours patients had 1.34 times longer time to embolization (95% CI: 1.02–1.76), however, regression analysis showed no strong association between time of admission and 30-day survival (odds ratio [OR] 2.13; 95% CI: 0.76–5.81). Time to embolization also showed no relationship with survival (OR 1.00; 95% CI: 1.00–1.00).
In their discussion, the authors underline the relatively low number of patients who underwent SAE for splenic injury within 24 hours of arrival at a MTC. They note that this “relatively low proportion reflects the prevailing UK trend toward non-operative management of splenic injury” with most patients managed conservatively.
They note that disparities in time to embolization between in-hours and out-of-hours presentations are suggestive of logistical and systemic factors, however, such as the availability of interventional radiology (IR) staff, activation of protocols or delayed imaging, which may impact access to timely care during nights and weekends, despite required 24-hour MTC coverage.
“The ongoing crisis in workforce planning in IR within the UK is well documented with many centres remaining understaffed on-call rota and reliant on locum cover or single-operator out-of-hours services,” Jenkins et al state.
“These observations highlight a broader structural question: Should IR have a more central embedded role within MTC trauma teams to ensure equitable access to time-critical embolization?” The authors write that, across UK centres, IR involvement remains “reactive”, thus, to strengthen operational integration, IR must be incorporated more fully within trauma team structures.
Despite longer out-of-hours delays, Jenkins and colleagues underscore that no association was observed between time to embolization and 30-day survival, yet state that this result may be due to patients dying before embolization or surgical intervention is possible due to severe bleeding with haemodynamic instability.
With an overall 30-day survival of 87%, the authors suggest that there is “limited scope” for time optimisation alone, concluding that, overall, their observations suggest survival is likely determined by injury, severity, age and systemic physiology than absolute time to embolization.
