Wu T, Weaver F, Katz S. Identification of a High-Risk Subset of Patients Undergoing Infrainguinal Bypass Surgery. JAMA Surg. 2015;150(1):82-84. doi:10.1001/jamasurg.2014.504
With the aging of the adult population, a significant increase in the number of procedures required to alleviate symptoms of lower extremity ischemia has occurred. The ability to predict either a major adverse limb event or a major adverse cardiac event following open infrainguinal revascularization may help us to select patients better served by a less invasive approach.
The American College of Surgeons National Surgical Quality Improvement Program database,1 encompassing an 8-year period, was analyzed. Patients undergoing infrainguinal revascularization by open bypass were identified. A major adverse limb event was defined as a deep incisional surgical site infection, an organ-space infection other than the incision, disruption of a surgical wound, graft failure, or a return to the operating room within 30 days, which includes amputations. A major adverse cardiac event was defined as a stroke, a myocardial infarction, cardiac arrest, or death within 30 days of operation. Preoperative risk factors and patient demographics were compared by use of χ2 analysis. Those factors found to be significant were placed in a series of logistic regression models to determine their individual significance. No institutional review board approval was needed because the National Surgical Quality Improvement Program database contains de-identified data.
Between 2005 and 2012, a total of 20 505 patients undergoing lower extremity bypass were identified in the National Surgical Quality Improvement Program database. The overall rates of a major adverse cardiac event and a major adverse limb event were 4.33% and 19.74%, respectively. In multivariate analysis, diabetes mellitus, a history of congestive heart failure, and steroid use were associated with a major adverse limb event (P < .05). An age of 80 years or older, dependent functional status, chronic obstructive pulmonary disease, myocardial infarction, previous coronary surgery, or a history of angina were associated with a major adverse cardiac event (P < .05). Dialysis dependence and an American Society of Anesthesiologists score of greater than 3 were associated with both events (Table 1). Patients with a dependent functional status, dialysis dependence, a history of angina, myocardial infarction, or congestive heart failure appear to be at a particularly high risk for a major adverse cardiac event or a major adverse limb event (Table 2).
For many years, infrainguinal bypass grafting has been the standard of treatment for patients with lower extremity ischemia. The advent of percutaneous treatments for peripheral arterial disease has significantly increased the number of options available for treating these patients. The low periprocedural morbidity and shortened hospital stays associated with catheter-based treatment must now be carefully weighed against the durability and proven effectiveness of lower extremity bypass.2 Many clinical variables must be considered in deciding the best method of treatment for those with lower extremity ischemia, including the availability of a conduit, the length and location of arterial occlusion, patient longevity, and the degree of limb ischemia, as well as periprocedural morbidity and mortality.3,4 In addition to the adverse effect on the individual patient, the societal consequences of major adverse limb events (especially wound infection and graft failure) and major adverse cardiac events have been well documented.5
We acknowledge that the inability to distinguish the number of adverse events by indication for operation is a limitation of our study. However, identification of a patient group at heightened risk for complications following open bypass might aid in helping to plan the most appropriate treatment for each individual patient. Patients with intermittent claudication who have any of the risk factors already mentioned may best be treated with an extended trial of nonoperative management. Those with limb-threatening ischemia amenable to angioplasty may best be initially treated with catheter-based therapy, whereas patients not suitable for percutaneous intervention, especially those at highest risk for a major adverse cardiac event or a major adverse limb event, might be offered intensive supportive care or primary amputation. We conclude that preoperative risk factors can be used to identify a subset of patients with an elevated risk of a major adverse cardiac event or a major adverse limb event. Although this should not absolutely preclude the use of open bypass surgery for these patients, other less invasive therapeutic interventions (or conservative management) may be better first-line treatment alternatives.
Corresponding Author: Steven Katz, MD, Department of Medical Education, Huntington Hospital, 100 W California Blvd, Pasadena, CA 91105 (email@example.com).
Published Online: November 26, 2014. doi:10.1001/jamasurg.2014.504.
Author Contributions: Dr Wu had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: All authors.
Acquisition, analysis, or interpretation of data: Wu.
Drafting of the manuscript: Wu, Katz.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Wu.
Administrative, technical, or material support: Weaver.
Study supervision: Katz.
Conflict of Interest Disclosures: None reported.
Disclaimer: The American College of Surgeons National Surgical Quality Improvement Program and the participating hospitals are the sources of the data used herein; they have not verified and are not responsible for the statistical validity of the data analysis or the conclusions derived by the authors.
Previous Presentation: This paper was presented at the 85th Annual Meeting of the Pacific Coast Surgical Association; February 15, 2014; Dana Point, California.