Intraoperative Transit-Time Flow as a Predictor of Failure after Infrainguinal Revascularization with Heparin-Bonded Expanded Polytetrafluoroethylene Graft.

BACKGROUND: The heparin-bonded expanded polytetrafluoroethylene (He-ePTFE) conduit is an option for patients requiring infrainguinal revascularization (iIR), but the risk of failure may be unpredictable, especially in cases with poor run-off. Intraoperative transit-time flow (TTF) provides an automated and quantitative analysis of flow and may serve as an adjunct evaluation during surgical revascularization. The aim of this study was to assess TTF in patients undergoing iIR with He-PTFE at 3 referral hospitals and to establish a predictive flow threshold for graft occlusion. METHODS: A prospective registry initiated in 2020 enrolled patients undergoing iIR using He-PTFE for critical limb ischemia or severe claudication, and TTF measurement was analyzed. Preoperative assessments of anatomical and clinical characteristics were available for all patients. The HT353 Optima Meter (Transonic Systems Inc., Ithaca, NY, USA) was used in all procedures according to a standardized protocol. The institutional ethics committee approved the study. A predictive model using receiver operating characteristic curve analysis was utilized to establish the threshold of flow, and variables were compared. Anatomical and clinical evaluation were reported according to Rutherford grade, Global Limb Anatomic System and Wound, Ischemia, and foot Infection classification. The main outcome considered was the correlation between TTF and graft occlusion. Secondary outcomes included survival, other predictors of graft occlusion, freedom from major adverse cardiovascular events, and freedom from major amputation. RESULTS: Among 68 patients, 55.8% had Rutherford 5-6, 45.6% had Global Limb Anatomic System 3 and 73.5% had Wound, Ischemia, and foot Infection 3-4. Distal anastomosis was at tibial level in 23.5% and mean diameter of conduit was 6.4 mm. Basal and postoperative TTF were 27.8 ± 15.6 ml/min and 109.0 ± 53.0 ml/min, respectively. After a mean follow-up of 18 ± 13 months, 7 (10.9%) patients presented graft occlusion and 5 (7.8%) required major amputation. TTF threshold = 80 ml/min revealed a sensitivity and specificity of 81.8% (95% confidence interval 48.2-97.7) and 80.7% (95% confidence interval 68.1-90.0) respectively, and it was selected as cut-off for graft occlusion. Freedom from graft occlusion in patients with TTF >80 ml/min vs. TTF ≤80 ml/min at 6, 12, and 24 months was 95.7% (standard error (SE) = 0.030) vs. 65.5% (SE = 0.115), 95.7% (SE = 0.030) vs. 58.9% (SE = 0.120) and 90.9% (SE = 0.054) vs. 51.6% (SE = 0.126), P = 0.0003. No statistical difference in primary patency, secondary patency and limb salvage was observed. At multivariate analysis, distal anastomosis at tibial vessel (odds ratio 8.50) and TTF ≤80 ml/min (odds ratio 9.39) were independent predictors of graft occlusion. CONCLUSIONS: These results suggest that TTF may serve as a valuable tool in the management of iIR. A TTF measurement of ≤80 ml/min should be regarded as a predictor of graft occlusion, prompting consideration of additional intraoperative maneuvers to enhance arterial flow. Caution should be exercised in patients requiring direct tibial artery revascularization, as it represents a predictor of failure independent of TTF levels. Larger cohorts of patients and longer follow-up periods are necessary to confirm these findings.

Intraoperative Predictors and Proposal for a Novel Prognostic Risk Score for In-Hospital Mortality after Open Repair of Ruptured Abdominal Aortic Aneurysms (SPARTAN Score).

(1) Background: Several mortality risk scores have been developed to predict mortality in ruptured abdominal aortic aneurysms (rAAAs), but none focused on intraoperative factors. The aim of this study is to identify intraoperative variables affecting in-hospital mortality after open repair and develop a novel prognostic risk score. (2) Methods: The analysis of a retrospectively maintained dataset identified patients who underwent open repair for rAAA from January 2007 to October 2023 in three Italian tertiary referral centers. Multinomial logistic regression was used to calculate the association between intraoperative variables and perioperative mortality. Independent intraoperative factors were used to create a prognostic score. (3) Results: In total, 316 patients with a mean age of 77.3 (SD ± 8.5) were included. In-hospital mortality rate was 30.7%. Hemoperitoneum (p < 0.001), suprarenal clamping (p = 0.001), and operation times of >240 min (p = 0.008) were negative predictors of perioperative mortality, while the patency of at least one hypogastric artery had a protective role (p = 0.008). Numerical values were assigned to each variable based on the respective odds ratio to create a risk stratification for in-hospital mortality. (4) Conclusions: rAAA represents a major cause of mortality. Intraoperative variables are essential to estimate patients' risk in surgically treated patients. A prognostic risk score based on these factors alone may be useful to predict in-hospital mortality after open repair.

Association Between the Lockdown for SARS-CoV-2 (COVID-19) and Reduced Surgical Site Infections after Vascular Exposure in the Groin at Two Italian Academic Hospitals.

BACKGROUND: The aim of this study was to evaluate whether the scrupulous hygiene rules and the restriction of contacts during the lockdown owing to the COVID-19 pandemic affected the rate and severity of surgical site infections (SSI) after vascular exposure in the groin at two Italian University Hospitals. METHODS: Starting from March 2020, strict hygiene measures for protection of health care workers (HCW) and patients from COVID-19 infection were implemented, and partly lifted in July 2020. The main exposure for analysis purposes was the period in which patients were operated. Accordingly, study subjects were divided into two groups for subsequent comparisons (preCOVID-19 era: March-June 2018-2019 versus COVID-19 era: March-June 2020). The primary endpoint was the occurrence of superficial and/or deep SSI within 30 days after surgery. The Centers for Disease Control and Prevention definitions were used to classify superficial and deep SSI. RESULTS: A total of 194 consecutive patients who underwent vascular exposure in the groin were retrospectively analyzed. Of those, 60 underwent surgery from April 1, 2018 to June 30 of the same year; 83 from April 1, 2019 to June 30 of the same year; and 51 from April 1, 2020 to June 30 of the same year. The mean age of the study cohort was 75 years and 140 (72%) were males. Patients who were operated in the COVID-19 era were less likely to develop SSI (10% vs. 28%; P = 0.008), including both deep SSI (4% vs. 13%; P = 0.04) and superficial SSI (6% vs. 15%; P = 0.05). After multivariate adjustments, being operated in the COVID-19 era was found to be a negative predictor for development of an SSI (odds ratio [OR] = 0.31; 95% confidence interval [CI] = 0.09-0.76; P < 0.001) or deep SSI (OR = 0.21; 95% CI = 0.03-0.98; P < 0.001). Operative time was also found as independent predictor for the development of deep SSI (OR = 1.21; 95%CI = 1.21-1.52; P = 0.02). Using binary logistic regression, there were no independent predictors of superficial SSI that could be identified. CONCLUSIONS: Vascular exposure in the groin carries a non-negligible risk of SSI. In this study, we provided important insights that are simple and easily viable precautions (such as the universal use of surgical masks both for patients and health care professionals during wound care, the widespread diffusion of hand sanitizers, and the reduction of the number of visitors in the surgical wards) could be promising and safe tools for SSI risk reduction.