Is incidental splenectomy during thoracoabdominal aortic aneurysm repair associated with reduced survival?

OBJECTIVE: The effect of incidental splenectomy during thoracoabdominal aortic aneurysm repair is unknown. We hypothesized incidental splenectomy was associated with decreased late survival. METHODS: We studied 1056 thoracoabdominal aortic aneurysm repairs from 2006 to 2016. Exclusion criteria were age less than 18 years (n = 9), prior splenectomy (n = 2), and intraoperative death (n = 3). This left 1042 thoracoabdominal aortic aneurysm repairs for analysis (median age, 65 years; interquartile range, 56-72), including 221 (21%) that were reoperations. Multivariable modeling identified predictors of operative mortality in the total cohort. Moreover, to adjust for baseline differences, propensity score matching was performed to examine the frequency of these outcomes in the total cohort (n = 132 pairs) and the early survivors (n = 110 pairs). Late survival was estimated by the Kaplan-Meier method, and risk of late mortality was assessed by Cox proportional hazards regression. RESULTS: Incidental splenectomy was performed in 135 patients (13%), 36% of whom underwent reoperation. Operative mortality rates of the incidental splenectomy and nonincidental splenectomy groups were 16% versus 8% in both the overall study (P = .005) and the propensity score-matched (P = .07) cohorts. In multivariable analysis, incidental splenectomy independently predicted operative mortality (odds ratio, 2.2; 95% confidence interval, 1.21-3.94; P = .008). For early survivors, incidental splenectomy did not increase the risk of late mortality. Survival estimates of matched early survivors did not differ between the incidental splenectomy and nonincidental splenectomy groups (P = .29). CONCLUSIONS: Incidental splenectomy during thoracoabdominal aortic aneurysm repair was associated with increased operative mortality but not reduced late survival. Splenic preservation is encouraged when feasible.