The effect of intercostal artery reimplantation on spinal cord injury in thoracoabdominal aortic aneurysm surgery

Objective: Intercostal artery (ICA) reimplantation (ICAR) is thought to decrease spinal cord injury (SCI) in thoracic aortic aneurysm and thoracoabdominal aortic aneurysm (TAAA) surgery. Patients treated from 1989 to 2005 without ICAR were compared with those treated from 2005 to 2013 with ICAR to determine whether ICAR reduced SCI. We hypothesized that ICAR would reduce SCI, especially in the highest-risk patients. Methods: This was a retrospective analysis using a prospectively maintained Investigational Review Board-approved database from a university tertiary referral center. The analysis included all patients (n = 805) undergoing thoracic aortic aneurysm and TAAA surgery from 1989 to 2013. The main outcome measure was any transient or permanent paraplegia or paraparesis (SCI). From 1989 to 2004, ICAR was not performed in patients, and open ICAs were ligated; from 2005 to 2013, open ICAs at T7 to L2 were reimplanted in patients with Crawford type I, II, and III TAAAs. Surgical technique was cross clamp without assisted circulation. Anesthetic management was the same from 1989 to 2013. Demographic, intraoperative, and outcome variables were assessed by univariate and multivariate analysis. Observed/expected ratios for paralysis were calculated. Results: A total of 540 patients had surgery before 2005, and 265 had surgery after 2005, when ICAR was begun. There were 275 type I, II, and III TAAAs before 2005 and 164 after 2005. Aneurysm extent, acuity, SCI, mortality, renal failure, and pulmonary failure were the same in patients treated before and after 2005. Multivariate modeling of all patients showed type II TAAA (P = .0001), dissection (P = .00015), and age as a continuous variable (P = .0085) were significant for SCI. Comparing only type I, II, and III TAAAs, there was no difference in SCI between those with ICAR after 2005 and those without ICAR before 2005 (5.1% vs 8.8%; P = .152). In a subanalysis of the highest-risk patients (type II, dissection, acute), ICAR was not significant (P = .27). Observed/expected ratios ratios were 0.23 before 2005 and 0.16 after 2005 (chi(2) = .796; P = .37). Conclusions: Although there was a small decrease in SCI with ICAR, reattaching ICAs did not produce a statistically significant reduction in SCI, even in the highest-risk patients.