Influence of Interhospital Transfer on Outcomes of Symptomatic and Ruptured Abdominal Aortic Aneurysms.

Introduction: Symptomatic or ruptured abdominal aortic aneurysms (rAAA) maintains a high mortality index despite technical advances in its treatment. The influence of patients' geographic location on rAAA outcomes, when the rupture occurs or when the AAA becomes symptomatic, has not been a commonly studied issue. Due to the lack of research on this matter, the impact of interhospital transfer on mortality is ambiguous.

Objective: Evaluate the influence of the geographic location of patients with symptomatic AAA or rAAA on AAA mortality.

Methods: Retrospective review of all cases of symptomatic AAA and rAAA submitted to surgery in a tertiary institution, between January 2011 and August 2017. The main outcome was in-hospital mortality. Secondary outcomes were admission to intensive care unit (ICU), length of ICU and hospital stay, type of repair and anesthesia and weekend presentation. Data was submitted to univariable analysis and logistic regression. Statistical significance was considered if the p value was <0.05.

Results: During the defined period of 80 months, a total of 135 patients were admitted with the diagnosis of symptomatic or rAAA and submitted to surgery. Most patients had a ruptured AAA (90.4%, n=122), while symptomatic AAA represented a minority (9.6%, n=13). All patients (91.1% male gender, mean age 74±10 years) were submitted to surgery, 83 (61.5%) by endovascular repair and 52 (38.5%) by open repair, 30.4% with local anesthesia and sedation (n=41), all in the endovascular group. 92 patients (68.1%) were transferred from other hospitals, with a mean distance of 113±88 km. In this cohort, in-hospital mortality was 31.5% in transferred patients and 34.9% in not transferred patients. Subgroup analysis revealed that there were no significant differences between transferred and not transferred patients' groups concerning main outcome (p=0.35), baseline characteristics (age and gender), type of surgery and anesthesia, weekend presentation, ICU admission, length of ICU and hospital stay. Logistic regression analysis revealed that the variables associated with mortality were female gender (odds ratio [OR] 2.28; 95% confidence interval [CI] 1.40-3.70; p<0.01), open repair (OR 2.79; 95% CI 1.68-4.63; p<0.01) and general anesthesia (OR 9.16; 95% CI 2.33-36.06; p<0.01).

Conclusion: Our study revealed that transfer of patients for urgent repair of AAA was not associated with an increased mortality. The hypothetical increased mortality due to transfer might have been compensated by endovascular treatment and local anesthesia in some cases. Further studies must be carried out, particularly comparing endovascular and open repair in emergency setting.