Risk Factors for Surgical Site Infection after Lower Limb Revascularisation Surgery: a Systematic Review and Meta-Analysis of Prognostic Studies

Objective To systematically review and meta-analyse adjusted risk factors for surgical site infection (SSI) after lower limb revascularisation surgery. Data Sources MEDLINE, Embase, Evidence Based Medicine Reviews, and the Cochrane Central Register of Controlled Trials (inception to 28 April 2022). Review Methods Systematic review and meta-analysis conducted according to PRISMA guidelines. After protocol registration, databases were searched. Studies reporting adjusted risk factors for SSI in adults who underwent lower limb revascularisation surgery for peripheral artery disease were included. Adjusted odds ratios (ORs) were pooled using random effects models. GRADE was used to assess certainty. Results Among 6 377 citations identified, 50 studies (n = 271 125 patients) were included. The cumulative incidence of SSI was 12 (95% confidence interval [CI] 10 – 13) per 100 patients. Studies reported 139 potential SSI risk factors adjusted for a median of 12 (range 1 – 69) potential confounding factors. Risk factors that increased the pooled adjusted odds of SSI included: female sex (pooled OR 1.41, 95% CI 1.20 – 1.64; high certainty); dependent functional status (pooled OR 1.18, 95% CI 1.03 – 1.35; low certainty); being overweight (pooled OR 1.82, 95% CI 1.29 – 2.56; moderate certainty), obese (pooled OR 2.20, 95% CI 1.44 – 3.36; high certainty), or morbidly obese (pooled OR 1.65, 95% CI 1.08 – 2.52; moderate certainty); chronic obstructive pulmonary disease (pooled OR 1.42, 95% CI 1.17 – 1.71; high certainty); chronic limb threatening ischaemia (pooled OR 1.67, 95% CI 1.22 – 2.29; moderate certainty); chronic kidney disease (pooled OR 2.13, 95% CI 1.18 – 3.83; moderate certainty); intra-operative (pooled OR 1.23, 95% CI 1.02 – 1.49), peri-operative (pooled OR 1.92, 95% CI 1.27 – 2.90), or post-operative (pooled OR 2.21, 95% CI 1.44 – 3.39) blood transfusion (moderate certainty for all); urgent or emergency surgery (pooled OR 2.12, 95% CI 1.22 – 3.70; moderate certainty); vein bypass and or patch instead of endarterectomy alone (pooled OR 1.86, 95% CI 1.33 – 2.59; moderate certainty); an operation lasting ≥ 3 hours (pooled OR 1.86, 95% CI 1.33 – 2.59; moderate certainty) or ≥ 5 hours (pooled OR 1.60, 95% CI 1.18 – 2.17; moderate certainty); and early or unplanned re-operation (pooled OR 4.50, 95% CI 2.18 – 9.32; low certainty). Conclusion This systematic review identified evidence informed SSI risk factors following lower limb revascularisation surgery. These may be used to develop improved SSI risk prediction tools and to identify patients who may benefit from evidence informed SSI prevention strategies. To systematically review and meta-analyse adjusted risk factors for surgical site infection (SSI) after lower limb revascularisation surgery. MEDLINE, Embase, Evidence Based Medicine Reviews, and the Cochrane Central Register of Controlled Trials (inception to 28 April 2022). Systematic review and meta-analysis conducted according to PRISMA guidelines. After protocol registration, databases were searched. Studies reporting adjusted risk factors for SSI in adults who underwent lower limb revascularisation surgery for peripheral artery disease were included. Adjusted odds ratios (ORs) were pooled using random effects models. GRADE was used to assess certainty. Among 6 377 citations identified, 50 studies (n = 271 125 patients) were included. The cumulative incidence of SSI was 12 (95% confidence interval [CI] 10 – 13) per 100 patients. Studies reported 139 potential SSI risk factors adjusted for a median of 12 (range 1 – 69) potential confounding factors. Risk factors that increased the pooled adjusted odds of SSI included: female sex (pooled OR 1.41, 95% CI 1.20 – 1.64; high certainty); dependent functional status (pooled OR 1.18, 95% CI 1.03 – 1.35; low certainty); being overweight (pooled OR 1.82, 95% CI 1.29 – 2.56; moderate certainty), obese (pooled OR 2.20, 95% CI 1.44 – 3.36; high certainty), or morbidly obese (pooled OR 1.65, 95% CI 1.08 – 2.52; moderate certainty); chronic obstructive pulmonary disease (pooled OR 1.42, 95% CI 1.17 – 1.71; high certainty); chronic limb threatening ischaemia (pooled OR 1.67, 95% CI 1.22 – 2.29; moderate certainty); chronic kidney disease (pooled OR 2.13, 95% CI 1.18 – 3.83; moderate certainty); intra-operative (pooled OR 1.23, 95% CI 1.02 – 1.49), peri-operative (pooled OR 1.92, 95% CI 1.27 – 2.90), or post-operative (pooled OR 2.21, 95% CI 1.44 – 3.39) blood transfusion (moderate certainty for all); urgent or emergency surgery (pooled OR 2.12, 95% CI 1.22 – 3.70; moderate certainty); vein bypass and or patch instead of endarterectomy alone (pooled OR 1.86, 95% CI 1.33 – 2.59; moderate certainty); an operation lasting ≥ 3 hours (pooled OR 1.86, 95% CI 1.33 – 2.59; moderate certainty) or ≥ 5 hours (pooled OR 1.60, 95% CI 1.18 – 2.17; moderate certainty); and early or unplanned re-operation (pooled OR 4.50, 95% CI 2.18 – 9.32; low certainty). This systematic review identified evidence informed SSI risk factors following lower limb revascularisation surgery. These may be used to develop improved SSI risk prediction tools and to identify patients who may benefit from evidence informed SSI prevention strategies.