The search for modifiable risk factors to improve bypass results is “worth the effort”


A large study of the outcomes of 3,033 patients undergoing lower extremity bypass has reported a 10.6% infection rate and identified procedural risk factors. As reported in the June edition of the Journal of Vascular Surgery, vascular surgeon Peter Henke and researchers from the University of Michigan, Ann Arbor, USA, used data from the Blue Cross Blue Shield of Michigan Cardiovascular Consortium Vascular Intervention Collaborative (BMC2 VIC) to carry out the study.

“During lower extremity revascularisation, high-risk surgical patients experience significant rates of wound infection, prolonged hospital stay and readmission, as well as graft failure and limb loss,” the authors explain.

Previous studies have found that risk factors are obesity, dialysis dependence, hypertension and the use of antiplatelet medications. Henke and colleagues report that this study found the following procedural risk factors also contributing to adverse outcomes:

  • Procedural length (>240 minutes)
  • Peak glucose (>180mg/dL)
  • Iodine-based skin preparation at the time of surgery.

“Although some factors such as patient co-morbidities are not modifiable, others represent areas of target for quality improvement for at risk patients,” noted Frank Davis, first author on the study. “Diligence should be devoted to decreasing operative length, controlling intraoperative glucose levels and avoiding iodine-only skin preparation.”

Patients with critical limb ischaemia often require surgical bypass when endovascular procedures are not possible or unsuccessful. Since autologous vein provides the best outcomes for graft patency, vein harvest, along with exposure of the femoral artery, puts this difficult patient population at risk for groin incision complications, noted to be as high as 23%.

“Identification of modifiable risk factors, particularly those involving operative technique, may provide further opportunity to improve patient outcomes and reduce hospital costs,” the authors write. “Ultimately the care of these complex patients comes down to attention to detail.  Doing so provides us with quality, less costly outcomes from which we all benefit.”