Efficacy of Strategies Intended to Prevent Surgical Site Infection After Lower Limb Revascularization Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

The Role of the Omniflow II Biosynthetic Graft in Postoperative Wound Problems After Lower Limb Revascularization: A Single Center Prospective Registry

OBJECTIVE

To investigate the role of the Omniflow II prosthesis in the prevention of vascular graft infection (VGI) in patients with peripheral arterial disease and to report on short-and mid-term graft-related morbidity.

MATERIAL AND METHODS

Patients were included in prospective registry between October 2019 and March 2023. The primary endpoint was to report infection-related problems, operation-related wound problems, and short- and mid-term graft-related morbidity. Secondary endpoint was to report the bypass patency rates and limb salvage rates.

RESULTS

A total of 146 Omniflow II grafts were implanted in 125 patients. Sixty-seven patients (45.9%) received a femoral interposition graft, and 77 patients (52.7%) underwent ipsilateral bypass surgery (femoropopliteal or femorocrural). Forty-one patients (28.1%) underwent crural bypass surgery. Seventy-six patients (52.1%) had previous vascular operation in the groin. The mean follow-up time was 352 days (range 0-1108 days). 3.4% of the patients suffered a wound infection limited to the dermis, and in 8.2%, the subcutaneous tissue was involved. Five early VGI (3.4%) and one late VGI (0.7%) occurred. One year primary patency rate of above-the-knee bypass was significantly better compared to the bypass below the knee (74.5% ± 0.131 versus 54% ± 0.126 (P = 0.049)). This difference was not significantly different when below-the-knee bypass surgery was compared with crural bypass surgery (54% ± 0.126 versus 23.8% ± 0.080 (P = 0.098)).

CONCLUSIONS

The performance of the Omniflow II prosthesis in the preventive setting is highly influenced by the anatomic location of the distal anastomosis. No influence on the incidence of postoperative wound problems could be observed. The rate of Omniflow II VGI in a high-risk population is similar to reported outcomes in other prosthetic grafts.

A systematic review and meta-analysis of outcomes associated with development of surgical site infection after lower-limb revascularization surgery

OBJECTIVES

Although surgical site infection (SSI) is a commonly used quality metric after lower-limb revascularization surgery, outcomes associated with development of this complication are poorly characterized. We conducted a systematic review and meta-analysis of studies reporting associations between development of an SSI after these procedures and clinical outcomes and healthcare resource use.

METHODS

We searched MEDLINE, Embase, CENTRAL, and Evidence-Based Medicine Reviews (inception to April 4th, 2023) for studies examining adjusted associations between development of an SSI after lower-limb revascularization surgery and clinical outcomes and healthcare resource use. Two investigators independently screened abstracts and full-text citations, extracted data, and assessed risk of bias. Data were pooled using random-effects models. Heterogeneity was assessed using I2 statistics. GRADE was used to assess estimate certainty.

RESULTS

Among 6671 citations identified, we included 11 studies (n = 61,628 total patients) that reported adjusted-associations between development of an SSI and 13 different outcomes. Developing an SSI was associated with an increased adjusted-risk of hospital readmission (pooled adjusted-risk ratio (aRR) = 3.55; 95% CI (confidence interval) = 1.40-8.97; n = 4 studies; n = 13,532 patients; I2 = 99.0%; moderate certainty), bypass graft thrombosis within 30-days (pooled aRR = 2.09; 95% CI = 1.41-3.09; n = 2 studies; n = 23,240 patients; I2 = 51.1%; low certainty), reoperation (pooled aRR = 2.69; 95% CI = 2.67-2.72; n = 2 studies; n = 23,240 patients; I2 = 0.0%; moderate certainty), bleeding requiring a transfusion or secondary procedure (aRR = 1.40; 95% CI = 1.26-1.55; n = 1 study; n = 10,910 patients; low certainty), myocardial infarction or stroke (aRR = 1.21; 95% CI = 1.02-1.43; n = 1 study; n = 10,910 patients; low certainty), and major (i.e., above-ankle) amputation (pooled aRR = 1.93; 95% CI = 1.26-2.95; n = 4 studies; n = 32,859 patients; I2 = 83.0; low certainty). Development of an SSI >30-days after the index operation (aRR = 2.20; 95% CI = 1.16-4.17; n = 3 studies; n = 21,949 patients; low certainty) and prosthetic graft infection (aRR = 6.72; 95% CI = 3.21-12.70; n = 1 study; n = 272 patients; low certainty) were both associated with an increased adjusted-risk of major amputation. Prosthetic graft infection was also associated with an increased adjusted-risk of mortality >30-days after the index procedure (aRR = 6.40; 95% CI = 3.32-12.36; n = 1 study; n = 272 patients; low certainty).

CONCLUSIONS

This systematic review and meta-analysis suggests that development of an SSI after lower-limb revascularization surgery significantly increases patient morbidity and healthcare resource use. SSI is therefore a valuable quality metric after these surgeries. However, current estimates are based on heterogenous, low-to-moderate certainty evidence and should be confirmed by large, multicenter, cohort studies.

Prediction Models for Forecasting Risk of Development of Surgical Site Infection after Lower Limb Revascularization Surgery: A Systematic Review

BACKGROUND

Surgical site infections (SSIs) are a common and potentially preventable complication of lower limb revascularization surgery associated with increased healthcare resource utilization and patient morbidity. We conducted a systematic review to evaluate multivariable prediction models designed to forecast risk of SSI development after these procedures.

METHODS

After protocol registration (CRD42022331292), we searched MEDLINE, EMBASE, CENTRAL, and Evidence-Based Medicine Reviews (inception to April 4th, 2023) for studies describing multivariable prediction models designed to forecast risk of SSI in adults after lower limb revascularization surgery. Two investigators independently screened abstracts and full-text articles, extracted data, and assessed risk of bias. A narrative synthesis was performed to summarize predictors included in the models and their calibration and discrimination, validation status, and clinical applicability.

RESULTS

Among the 6,671 citations identified, we included 5 studies (n = 23,063 patients). The included studies described 5 unique multivariable prediction models generated through forward selection, backward selection, or Akaike Information Criterion-based methods. Two models were designed to predict any SSI and 3 Szyilagyi grade II (extending into subcutaneous tissue) SSI. Across the 5 models, 18 adjusted predictors (10 of which were preoperative, 3 intraoperative, and 5 postoperative) significantly predicted any SSI and 14 adjusted predictors significantly predict Szilagyi grade II SSI. Female sex, obesity, and chronic obstructive pulmonary disease significantly predicted SSI in more than one model. All models had a "good fit" according to the Hosmer-Lemeshow test (P > 0.05). Model discrimination was quantified using the area under the curve, which ranged from 0.66 to 0.75 across models. Two models were internally validated using non-exhaustive twofold cross-validation and bootstrap resampling. No model was externally validated. Three studies had a high overall risk of bias according to the Prediction model Risk Of Bias ASsessment Tool (PROBAST).

CONCLUSIONS

Five multivariable prediction models with moderate discrimination have been developed to forecast risk of SSI development after lower limb revascularization surgery. Given the frequency and consequences of SSI after these procedures, development and external validation of novel prediction models and comparison of these models to the existing models evaluated in this systematic review is warranted.

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.

Prediction models of surgical site infection after gastrointestinal surgery: a nationwide prospective cohort study

OBJECTIVE

This study aimed to construct and validate a clinical prediction model for surgical site infection (SSI) risk 30 days after gastrointestinal surgery.

MATERIALS AND METHODS

This multicentre study involving 57 units conducted a 30-day postoperative follow-up of 17 353 patients who underwent gastrointestinal surgery at the unit from 1 March 2021 to 28 February 2022. The authors collected a series of hospitalisation data, including demographic data, preoperative preparation, intraoperative procedures and postoperative care. The main outcome variable was SSI, defined according to the Centres for Disease Control and Prevention guidelines. This study used the least absolute shrinkage and selection operator (LASSO) algorithm to screen predictive variables and construct a prediction model. The receiver operating characteristic curve, calibration and clinical decision curves were used to evaluate the prediction performance of the prediction model.

RESULTS

Overall, 17 353 patients were included in this study, and the incidence of SSI was 1.6%. The univariate analysis combined with LASSO analysis showed that 20 variables, namely, chronic liver disease, chronic kidney disease, steroid use, smoking history, C-reactive protein, blood urea nitrogen, creatinine, albumin, blood glucose, bowel preparation, surgical antibiotic prophylaxis, appendix surgery, colon surgery, approach, incision type, colostomy/ileostomy at the start of the surgery, colostomy/ileostomy at the end of the surgery, length of incision, surgical duration and blood loss were identified as predictors of SSI occurrence ( P <0.05). The area under the curve values of the model in the train and test groups were 0.7778 and 0.7868, respectively. The calibration curve and Hosmer-Lemeshow test results demonstrated that the model-predicted and actual risks were in good agreement, and the model forecast accuracy was high.

CONCLUSIONS

The risk assessment system constructed in this study has good differentiation, calibration and clinical benefits and can be used as a reference tool for predicting SSI risk in patients.

Significance and current approaches to vascular graft infection

Vascular graft/endograft infection (VGEI) is a constant in cardiovascular surgery with published rates between 1 and 5%. Every graft type and anatomical location is a potential target for infectious complications. These patients are sick patients with high frailty burden. Management of VGEI entails a multidisciplinary and multimodality approach. Here we review some aspects of the problem of VGEI including prevention, diagnosis, and surgical therapy with focus on recent developments in the field.