General Anesthesia Associated With Increased Blood Transfusions and Multiple Complications Following Above Knee Amputation in a Large Veterans Administration Cohort

Abstract

It is generally accepted that the use of general anesthesia in lower extremity amputations does not correlate with adverse cardiac outcomes or increased mortality as compared to regional or spinal anesthesia; however, published studies consider lower extremity amputations as a whole without addressing above the knee amputation (AKA) outcomes specifically. No studies have examined this issue in a veteran population. We set forth to compare anesthesia-related AKA outcomes across the national veteran population using the Veteran’s Affairs Surgical Quality Improvement Program database. With institutional review board approval, a retrospective review of the Veteran’s Affairs Surgical Quality Improvement Program database was undertaken for all patients in the Veteran’s Affairs Health System who underwent AKA from 1999 to 2018. Patients were divided into two groups: those undergoing the AKA procedure with general anesthesia (G-A) vs other type of anesthesia (regional, spinal, epidural, nerve block [O-A]). Data collected included patient demographics, history of comorbid conditions, indication for procedure, mortality, postoperative blood use, and related outcomes. χ2 tests with Yates correction were employed to compare the G-A and O-A groups and a binary logistic regression model was applied to generate covariate-adjusted odds ratios with 95% confidence interval (SPSS software; version 25, IBM Corp, Armonk;, NY). There were 20,879 patients with an average age of 68.2 ± 10.5 years who underwent AKA (98.8% male) during the study period. There was no significant difference in average age or American Society of Anesthesiologists class between G-A and O-A. There was no significant difference between postoperative length of stay or postoperative rates of superficial or deep wound infections, wound dehiscence, cerebrovascular accident, pulmonary embolism, deep venous thrombosis, or progressive renal insufficiency between G-A and O-A. When adjusted for covariates, G-A corresponded to increased odds ratios (OR) for postoperative blood use (OR, 2.504; 95% confidence interval, 1.277-4912), sepsis (OR, 1.355; 95% confidence interval, 1.127-1.630), and cases with three or more complications (OR, 1.320; 95% confidence interval, 1.073-1.625) (Table). In a large veteran AKA cohort, G-A use was associated with increased postoperative blood use, multiple complication incidence, and sepsis development. Other forms of anesthesia were associated with slight increases in postoperative myocardial infarction and death within 30 days. Although these results support growing literature that the use of general anesthesia does not negatively influence mortality in lower extremity amputations, they also suggest that several measures of postoperative complications may be increased with general anesthesia use in AKA patients specifically. Vascular practices and anesthesiologists should consider these trends when selecting anesthesia type for lower extremity amputations.TableAdjusted analysisPostoperative outcomeG-A (n = 14,549)O-A (n = 6330)P valueReturn to operating room within 30 days2241 (15.4)731 (11.5).0001Myocardial infarction131 (0.9)88 (1.4).003Bleeding requiring more than 4 blood units78 (0.5)11 (0.2).0003Postoperative sepsis529 (3.6)173 (2.7).001Death within 30 days2131 (14.6)1031 (16.3).003G-A, General anesthesia; O-A, other anesthesia.Values are number (%). Open table in a new tab