T. Obeid1, K. Yin1, A. Kilic1, I. Arhuidese1, B. Nejim1, M. Malas1 1Johns Hopkins University School Of Medicine,Surgery,Baltimore, MD, USA
Introduction:
Open repair of thoracoabdominal aneurysm (TAA) and descending thoracic aneurysm (DTA) carries significant operative morbidity and mortality. Despite improved patient selection, evolving operative and anesthesia techniques, and better control of comorbid conditions, patient-level risk factors of open repair remain to be fully understood. We sought to evaluate risk factors affecting operative mortality of open TAA and DTA repair in a nationally validated multi-specialty dataset.
Methods:
We identified all TAA – including all Crawford extent types – and DTA cases in the National Surgical Quality Improvement Program (NSQIP) database between years 2005 to 2013. Operative mortality was defined as death within 30 days of surgery. A logistic regression model was constructed to evaluate the risk of patient’s age, gender, race, body mass index (BMI), comorbid conditions, functional status, American Society of Anesthesiologists (ASA) class, smoking status, alcohol intake, preoperative blood transfusion, rupture status, DTA vs combined Crawford extents, operating surgical specialty, preoperative hematocrit and creatinine levels.
Results:
A total of 1,048 patients had open TAA or DTA repair during the 9-year study period. Mean patient age was 67±12 years, BMI average was 27±6 and males comprised 60% of the dataset. Nearly 12.0 % of the patients presented with ruptured aneurysms. DTA comprised 10.6% of all aneurysms and concomitant dissection occurred in 12.7% of all cases.
Operative mortality was 14.0% (non-ruptured 11.4% vs. ruptured 34.2%, P<0.001) and the total proportion of patients with postoperative acute renal failure requiring dialysis was 12.6% (non-ruptured 11.8% vs ruptured 19.2%, P<0.001).
Each additional year in patient age or one unit increase in BMI increased the risk of death by 4% (OR 1.04, 95%CI 1.02-1.06, P<0.001, OR 1.04, 95%CI 1.00-1.08, P=0.03, respectively). Ruptured aneurysms had double the operative mortality risk (OR 2.26, 95%CI 1.26-4.03, P=0.010).
Being totally dependent had the highest effect on operative mortality, tripling the risk of death (OR 3.39, 95%CI 1.60-7.19, P<0.001), while preoperative chronic renal insufficiency added 26% mortality risk per 1 unit increase in creatinine level (OR 1.26, 95%CI 1.04-1.52, P=0.020).
Being a smoker and ASA class ≥4 versus ≤3 each increased the chances of death by 60% and 70%, respectively (both P < 0.05) (Table).
Conclusion:
Despite corseted efforts, open repair of thoracoabdominal aneurysm carries significant morbidity and mortality. Patient age and BMI equally affect the risk of operative mortality. Ruptured aneurysms and patients’ functional status have the highest effect on risk of operative death.
