Vein harvesting technique for infrainguinal arterial bypass with great saphenous vein and its association with surgical site infection and graft patency

A Meta-Analysis to Derive Population-Based Quality Benchmarks of the Incidence of Surgical Site Infection after Lower Limb Revascularization Surgery

BACKGROUND

The reported incidence of surgical site infection (SSI) after lower limb revascularization surgery varies. We conducted a systematic review and meta-analysis of population-based studies reporting the incidence of SSI in adults who underwent these surgeries in high-income countries to derive SSI quality benchmarks.

METHODS

We searched MEDLINE, EMBASE, CENTRAL, and Evidence-Based Medicine Reviews (inception-to-April 28th, 2022) for population-based studies estimating the cumulative incidence of SSI among adults who underwent lower limb revascularization surgery for peripheral artery disease (PAD) in high-income countries. Two investigators independently screened abstracts and full-text articles, extracted data, and assessed risks of bias. We used random-effects models to pool data and GRADE to assess certainty.

RESULTS

Among 6,258 citations, we included 53 studies (n = 757,726 patients); 8 of which (n = 435,769 patients) reported nonoverlapping data that were meta-analyzed. The pooled cumulative incidence of any SSI was 6.0 in 100 patients [95% confidence interval (CI) = 4.3-8.0 in 100 patients; n = 8 studies; n = 435,769 patients; moderate certainty]. The cumulative incidence of Szilagyi grade I (cellulitis), grade II (subcutaneous tissue), and grade III (prosthetic graft) SSI was 6.5 in 100 patients (95% CI = 4.3-8.6 in 100 patients; n = 2 studies; n = 39,645 patients; low certainty), 2.1 in 100 patients (95% CI = 2.0-2.3 in 100 patients; n = 2 studies; low certainty), and 0.4 in 100 patients (95% CI = 0.4-0.4 in 100 patients; n = 1 study; n = 333,275 patients; low certainty), respectively. The pooled cumulative incidence of any early (in-hospital/≤30-days) and late (>30-days) SSI was 6.2 in 100 patients (95% CI = 4.4-8.0 in 100 patients; n = 7 studies; n = 431,273 patients; moderate certainty) and 3.7 in 100 patients (95% CI = 2.2-5.2 in 100 patients; n = 2 studies; n = 10,565 patients; low certainty), respectively.

CONCLUSIONS

This systematic review derived population-based benchmarks of the incidence of any SSI; Szilagyi I, II, and III SSI; and early and late SSI after lower limb revascularization surgery. These may be used by practicing surgeons and healthcare leaders/administrators to guide quality improvement efforts in the United States and perhaps other countries.

Long-term outcomes of great saphenous vein harvest techniques for infrainguinal arterial bypass in a Medicare-matched registry database

OBJECTIVE

Long-term outcomes for harvesting techniques for great saphenous vein (GSV) and its impact on the outcomes of infrainguinal arterial bypass remains largely unknown. Endoscopic GSV harvesting (EVH) has emerged as a less invasive alternative to conventional open techniques. Using the Vascular Quality initiative Vascular Implant Surveillance & Interventional Outcomes Network (VQI-VISION) database, we compared the long-term outcomes of infrainguinal arterial bypass using open and endoscopic GSV harvest techniques.

METHODS

Patients who underwent infrainguinal GSV bypass between 2010 and 2019 were identified in the VQI-VISION Medicare linked database. Long-term outcomes of major/minor amputations, and reinterventions up to 5 years of follow-up were compared between continuous incisions, skip incision, and EVH, with continuous incisions being the reference group. Secondary outcomes included 30- and 90-day readmission, in addition to surgical site infections and patency rates at 6 months to 2 years postoperatively. Survival analysis using Kaplan-Meier curves and Cox regression hazard models were utilized to compare outcomes between groups. To adjust for multiple comparisons between the study groups, a P value of 2.5% was considered significant.

RESULTS

Among the 8915 patients included in the study, continuous and skip vein harvest techniques were used in 44.4% and 43.4% of cases each, whereas 12.3% underwent EVH. The utilization of EVH remained relatively stable at around 12% throughout the study period. Compared with GSV harvest using continuous incisions, EVH was associated with higher rates of reintervention at 1 year (46.5% vs 41.3%; adjusted hazard ratio [aHR], 1.22; 95% confidence interval [CI], 1.06-1.41; P = .01]. However, no significant difference was observed between EVH and continuous incisions, and between skip and continuous incisions in terms of long-term reintervention or major and minor amputations on adjusted analysis. Compared with continuous incision vein harvest, both EVH and skip incisions were associated with lower surgical site infection rates within the first 6 months post-bypass (aHR, 0.53; 95% CI, 0.35-0.82 and aHR, 0.68; 95% CI, 0.53-0.87, respectively). Loss of primary, primary-assisted, and secondary patency was higher after EVH compared with continuous incision vein harvest. Among surgeons performing EVH, comparable long-term outcomes were observed regardless of low (<4 cases/year), medium (4-7 cases/year), or high procedural volumes (>7 cases/year).

CONCLUSIONS

Despite higher 1-year reintervention rates, EVH for infrainguinal arterial bypass is not associated with a significant difference in long-term reintervention or amputation rates compared with other harvesting techniques. These outcomes are not influenced by procedural volumes for EVH technique.

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.

Risk Analysis and Clinical Outcomes in Chronic Limb-threatening Ischemia Patients with Surgical Site Infection after Distal Bypass

BACKGROUND

A recent randomized control study showed that long-term outcomes after surgical revascularization were superior to those after endovascular treatment for cases with chronic limb-threatening ischemia (CLTI) with an appropriate single-segment great saphenous vein. However, surgical site infection (SSI) in CLTI cases after infrapoplital bypass also resulted in a prolonged hospital stay and poor outcomes, including graft disruption. The aim of the current study was to analyze risk factors for SSI in CLTI patients after distal bypass and to compare outcomes in patients with and without SSI.

METHODS

A total of 515 cases that underwent distal bypass at a single center between 2009 and 2022 were analyzed retrospectively. Comparisons were made between patients with and without SSI after distal bypass. The primary end point was limb salvage after distal bypass.

RESULTS

Of the 515 cases that underwent distal bypass, 79 (15%) had SSI. The risk factors for SSI were preoperative antibacterial drug use (P = 0.001), pedal bypass (P = 0.001), and prolonged operation time (≥150 min) (P = 0.010). The median hospital stay in SSI cases was longer than that in non-SSI cases (P < 0.001). Of 515 distal bypasses, 7 (1.3%) bypass grafts ruptured postoperatively due to SSI, and of these 7 cases, 6 ruptured during the day, 5 cases occurred within 1 month postoperatively, and 2 patients (29%) are alive without amputation. The mean follow-up period was 34 ± 30 months. During follow-up, 62 limbs (SSI cases, 19; non-SSI cases, 43) required major amputation and there were 234 deaths (SSI cases, 46; non-SSI cases, 188). The 1-, 3-, and 5-year limb salvage rates of 82%, 71%, and 62%, respectively, in SSI cases were significantly lower than those in non-SSI cases (P < 0.001). The 5-year survival rate of 29% in SSI cases showed a tendency to be lower than that in non-SSI cases (P = 0.058).

CONCLUSIONS

The limb salvage rate in SSI cases was lower than in non-SSI cases after distal bypass. Graft rupture due to SSI occurred at a rate of 1.3% and resulted in poor outcomes in most cases. SSIs adversely affect outcomes and further study is needed to identify methods to avoid SSI following distal bypass.

Lower Extremity Bypass

The original description of the lower extremity bypass (LEB) provided surgeons with a reliable method of limb revascularization. The tenets of the operation have formed the foundation for the advances of surgical care. A careful evaluation of the chronic limb-threatening ischemia patient due to the numerous comorbid conditions is paramount to obtain the best possible outcomes. Use of all adjuncts including judicious target vessels control, completion imaging, and vein harvesting techniques to ensure optimal outcomes because a functioning LEB remains a key to successful limb salvage.

A framework for perioperative care for lower extremity vascular bypasses: A Consensus Statement by the Enhanced Recovery after Surgery (ERAS®) Society and Society for Vascular Surgery

The Society for Vascular Surgery and the Enhanced Recovery After Surgery (ERAS) Society formally collaborated and elected an international, multi-disciplinary panel of experts to review the literature and provide evidence-based suggestions for coordinated perioperative care for patients undergoing infrainguinal bypass surgery for peripheral artery disease. Structured around the ERAS core elements, 26 suggestions were made and organized into preadmission, preoperative, intraoperative, and postoperative sections.

How to Prevent Surgical Site Infection in Vascular Surgery: A Review of the Evidence

BACKGROUND

This review aims to identify and review the current evidence for preventing postoperative surgical site infections in abdominal aortic aneurysm surgery or infrainguinal arterial surgery.

METHODS

Extended literature review of clinical trials that examined the prevention of postoperative surgical site infections in abdominal aortic aneurysm or infrainguinal arterial surgery. Searches were conducted on Ovid MEDLINE (1950 - 13 March 2020) using key terms for vascular surgery, surgical site infections and specific preventative techniques. Articles were included if they discussed a relationship between a preventative technique and surgical site infections in abdominal aortic aneurysm or infrainguinal arterial surgery. The GRADE guidelines were used to assess the quality of evidence.

RESULTS

21 techniques and 81 studies were included. Prophylactic antibiotics and negative pressure wound therapy have a high quality of evidence for the prevention of surgical site infections in abdominal aortic aneurysm or infrainguinal arterial surgery. A moderate quality evidence base was identified for gentamicin containing collagen implant (confined to high surgical site infection risk centers). Currently, there is a low or very low quality of evidence to suggest a reduction in the surgical site infection rate for combination therapy, glycaemic control, Methicillin-resistant Staphylococcus aureus screening and absorbable suture. Evidence suggests no beneficial effect for nutritional supplementation, chlorhexidine bath, hair removal therapy, Staphylococcus aureus nasal eradication, cyanoacrylate microsealant, silver grafts, rifampicin bonded grafts, triclosan coated suture and postoperative wound drains. Endoscopic saphenous vein harvest may reduce surgical site infection rate (very low quality of evidence) but may lower long-term patency. Autologous vein grafts may increase surgical site infections (very low quality of evidence) but may provide better long-term patency rates in above-knee infrainguinal bypass surgery. There was no identified evidence for perioperative normothermia, electrosurgical bipolar vessel sealer or Dermabond and Tegaderm for surgical site infection prevention in vascular surgery.

CONCLUSIONS

Prophylactic antibiotics and postoperative negative pressure wound therapy are effective in the prevention of postoperative surgical site infection in abdominal aortic aneurysm or infrainguinal arterial surgery. There exists a significant risk of bias in the literature for many preventative techniques and further studies are required to investigate the efficacy of gentamicin containing collagen implant, and specific combination therapies.

Effect of infrainguinal bypass tunneling technique on patency and amputation in patients with limb ischemia

OBJECTIVE

We investigated the association of tunneling technique on patency and amputation in patients undergoing lower extremity bypass for limb ischemia.

METHODS

The National Vascular Quality Initiative database infrainguinal bypass module from 2008 to 2017 was queried for analysis. We excluded cases with non-great saphenous vein grafts, grafts using multiple segments, aneurysmal disease indications, bypass locations outside the femoral to below the knee popliteal artery or tibial arteries, and missing data on tunneling type and limb ischemia. The main exposure variable was the tunneling type, subcutaneously vs subfascially. Our primary outcomes were primary patency and amputation. The secondary outcomes included primary-assisted patency and secondary patency. Univariate and multivariate logistic regression models were used.

RESULTS

A total of 5497 bypass patients (2835 subcutaneous and 2662 subfascial) were included. Age, race, graft orientation (reversed vs not reversed), bypass donor and recipient vessels, harvest type, end-stage renal disease, smoking, coronary artery bypass graft, congestive heart failure, P2Y12 inhibitor at discharge, surgical site infection at discharge, and indication (rest pain vs tissue loss vs acute ischemia) were analyzed for an association with the tunneling technique (P < .05). Multivariate analyses demonstrated that the tunneling type was not associated with primary patency, primary-assisted patency, secondary patency, or major amputation (P > .05).

CONCLUSIONS

Compared with subfascial tunneling, the superficial tunneling technique was not associated with primary patency or major amputation in limb ischemia patients undergoing infrainguinal bypass with a single-segment great saphenous vein.

Systematic review and meta-analysis of saphenous vein harvesting and grafting for lower extremity arterial bypass

OBJECTIVE

In the present systematic review and meta-analysis, we compared the short- and long-term outcomes of different harvesting and grafting techniques in patients undergoing lower extremity arterial bypass.

METHODS

We searched multiple electronic databases (up to December 1, 2019) for comparative trials investigating different harvesting and bypass grafting techniques.

RESULTS

We identified a total of 37 studies for our review. Skip incision harvesting showed a similar high primary patency rate (Peto odds ratio [OR], 0.93; 95% confidence interval [CI], 0.83-1.04; P = .20) with continuous incision harvesting and comparable low wound complication rates (relative risk, 1.55; 95% CI, 0.91-2.66; P = .11) with endoscopic harvesting. In situ bypass grafting a long-term patency similar to that of reversed grafting (Peto OR, 1.01; 95% CI, 0.75-1.37; P = .93). However, for femoropopliteal bypass, the reversed bypass grafting group had significantly lower 2-year (Peto OR, 0.63; 95% CI, 0.52-0.78; P < .001) and 5-year (Peto OR, 0.70; 95% CI, 0.50-0.98; P = .04) failure rates compared with the in situ bypass grafting group. For infrapopliteal bypass, the in situ bypass grafting group had significantly lower 1-year (Peto OR, 1.54; 95% CI, 1.04-2.28; P = .03), 2-year (Peto OR, 1.52; 95% CI, 1.15-2.02; P = .003), and 3-year (Peto OR, 2.14; 95% CI, 1.13-4.05; P = .02) failure rates.

CONCLUSIONS

Skip incision harvesting can be considered the first-line harvesting strategy. For patients undergoing femoropopliteal bypass, reversed bypass grafting seems to result in better long-term patency. In contrast, for those undergoing infrapopliteal bypass, in situ bypass grafting resulted in superior long-term patency.

Paneled Saphenous Vein Grafts Compared to Internal Jugular Vein Grafts in Venous Reconstruction after Pancreaticoduodenectomy

BACKGROUND

Venous resection during pancreaticoduodenectomy for the excision of pancreatic cancer allows for a more complete resection with negative margins, which increases survival. When the resected vein is greater than 3 cm, reconstruction with an interposition graft is recommended. However, consensus regarding the optimal venous conduit has not been reached. The objective of this study is to compare outcomes between the paneled saphenous vein graft (SVG) and internal jugular vein graft (IJVG) in portomesenteric venous reconstructions after pancreaticoduodenectomy.

METHOD

A retrospective review was performed of patients undergoing pancreaticoduodenectomy requiring an interposition graft for venous reconstruction between 2011 and 2019. Patients were stratified based on the type of conduit used (paneled SVG or IJVG). Preoperative patient characteristics, reconstruction details, and postoperative outcomes including graft patency were recorded.

RESULTS

During the study period, 18 patients met inclusion criteria (10 female, mean age: 63 years, age range: 41-82 years). Thirteen patients underwent reconstruction with paneled SVG and five with IJVG. Comparing SVG and IJVG groups, there were no significant differences in venous resection length, venous diameters at the resection margins, or splenic vein ligation rate. For the paneled SVG, the average length of harvested vein was 168 mm which rendered 3-paneled grafts with an average diameter of 12 mm. The time to complete the venous reconstructions did not differ between the two groups (SVG: 263+/-204 min, IJVG: 216+/-77 min, P = 0.63). There were five graft thrombosis, three in the SVG group (mean follow-up time of 17 months) and two in the IJVG group (mean follow-up time of 8 months). All but one of the graft thromboses occurred during the index hospitalization. There was one donor site seroma and wound dehiscence in the SVG group and none in the IJVG group. Hospital length of stay was longer for the IJVG group (IJVG: 15.2 days, SVG: 10.2 days, P = 0.03). However, in-hospital and late mortality did not differ between the groups.

CONCLUSIONS

Paneled SVG and IJVG are both versatile and durable conduits for venous reconstruction after pancreaticoduodenectomy, able to accommodate a wide range of venous defects. In this small series, SVG has comparable outcomes to IJVG. Paneled SVG is a suitable alternative to IJVG for portomesenteric reconstruction.

Vein Harvest Wound Healing after Bypass Surgery for Critical Limb Ischemia

BACKGROUND

Lower-limb revascularization surgery, especially when performed using the great saphenous vein, predisposes patients to major surgical trauma on initially ischemic tissue. Vein harvest wounds (VHWs) after infrainguinal revascularization heal slowly. This study's aim was to assess the factors associated with VHW healing after infrainquinal bypass surgery for critical limb ischemia (CLI).

METHODS

A retrospective patient record study was conducted. All patients with CLI who underwent infrainguinal bypass surgery with autologous vein graft between January 1, 2015, and December 31, 2017, in the Turku University Hospital, were included. Follow-up data were collected until February 28, 2018. The following data was collected from the patient files; risk factors, ankle-brachial indices (ABIs), systolic toe pressures (STPs), the presence of an ischemic ulcer, VHW dehiscence, and the time when the VHW was completely healed. Procedures with outflow vessels at either popliteal or tibial artery were analyzed separately. Descriptive and univariate statistical analyses were performed.

RESULTS

Altogether, 195 patients were operated on for CLI, of whom 133 (68.2%) patients had ischemic ulcers. The mean follow-up time was 535.0 days (range 3.0-1143.0 days). The mean ABI improvement was 0.49 (P = 0.00), and STP improvement, 39.9 mm Hg (P = 0.00). The median time taken when VHW was healed was 48.0 days (95% confidence interval [CI], 39.4-56.6) in patients without ischemic ulcers and 82.0 days (95% CI, 59.7-104.3) in patients with ischemic ulcers, P = 0.03. VHW in patients who underwent popliteal artery bypass (62 days, 95% CI, 12.9-93.0) healed faster than VHW in those who underwent tibial artery bypass (132 days, 95% CI, 48.0-93.0), P = 0.02. Risk factors and the preoperative or postoperative ABIs or STPs had no effect on VHW healing time.

CONCLUSIONS

VHW healing was remarkably slower after revascularization surgery in patients with an ischemic foot ulcer than in those without ischemic ulcers.

The protective role of Toll-like receptor 3 and type-I interferons in the pathophysiology of vein graft disease

BACKGROUND

Venous grafts are commonly used as conduits to bypass occluded arteries. Unfortunately, patency rates are limited by vein graft disease (VGD). Toll like receptors (TLRs) can be activated in vein grafts by endogenous ligands. This study aims to investigate the role of TLR3 in VGD.

METHODS

Vein graft surgery was performed by donor caval vein interpositioning in the carotid artery of recipient Tlr2^-/-, Tlr3^-/-, Tlr4^-/- and control mice. Vein grafts were harvested 7, 14 and 28d after surgery to perform immunohistochemical analysis. Expression of TLR-responsive genes in vein grafts was analysed using a RT²-profiler PCR Array. mRNA expression of type-I IFN inducible genes was measured with qPCR in bone marrow-derived macrophages (BMM).

RESULTS

TLR2, TLR3 and TLR4 were observed on vein graft endothelial cells, smooth muscle cells and macrophages. Tlr3^-/- vein grafts demonstrated no differences in vessel wall thickening after 7d, but after 14d a 2.0-fold increase (p = 0.02) and 28d a 1.8-fold increase (p = 0.009) compared to control vein grafts was observed, with an increased number of macrophages (p = 0.002) in the vein graft. Vessel wall thickening in Tlr4^-/- decreased 0.6-fold (p = 0.04) and showed no differences in Tlr2^-/- compared to control vein grafts. RT²-profiler array revealed a down-regulation of type-I IFN inducible genes in Tlr3^-/- vein grafts. PolyI:C stimulated BMM of Tlr3^-/- mice showed a reduction of Ifit1 (p = 0.003) and Mx1 (p < 0.0001) mRNA compared to control.

CONCLUSIONS

We here demonstrate that TLR3 can play a protective role in VGD development, possibly regulated via type-I IFNs and a reduced inflammatory response.

Phenylephrine infusion impact on surgical site infections after lower extremity bypass surgery

OBJECTIVE

Lower extremity bypass (LEB) operations have high rates of surgical site infections (SSI). Phenylephrine is a commonly used vasoconstrictor which may reduce skin blood flow and increase the likelihood of SSI in these patients. We studied the potential effect of phenylephrine infusion during LEB surgery on SSI.

METHODS

LEB cases and their demographic data were identified through the Vascular Quality Initiative registry. SSI in this population was identified using the hospital epidemiology surveillance database. Phenylephrine use in this population was identified through chart review.

RESULTS

We identified 699 patients who underwent LEB; 82 (11.7%) developed an SSI, and 244 of 698 (35.0%) were treated with phenylephrine infusion. In bivariate analysis, higher body mass index (28.8 kg/m² vs 27.3 kg/m²; P = .034), diabetes (14.6% vs 9.4%; P = .035), hypertension (12.6% vs 4.7%; P = .038), groin incision (13.2 vs 5.4%; P = .013) and longer procedure times (17.1% for >220 minutes and 8.9% for ≤220 minutes; P = .003) were associated with higher rates of SSI. Whereas phenylephrine infusion exhibited a trend toward a higher rate (14.8% vs 9.9%; P = .057). In the logistic regression model, diabetes (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.0-3.2; P = .032), total procedure time (OR, 1.85; 95% CI, 1.1-3.1; P = .026) and vertical groin incision (OR, 2.6; 95% CI, 1.1-6.5; P = .035) were independent predictors of increased SSI rates, whereas body mass index (OR, 1.04; 95% CI, 0.99-1.08; P = .09), hypertension (OR, 2.5; 95% CI, 0.6-10.9; P = .22), and phenylephrine infusion (OR, 1.08; 95% CI, 0.63-1.85; P = .78) were not independent predictors of increased SSI rates.

CONCLUSIONS

Phenylephrine infusion did not increase the risk of SSI in patients who underwent LEB.

Efficacy of Preoperative Color Doppler Sonography of Lower Extremity Veins on Postoperative Outcomes in Candidates of Saphenectomy: A Randomized Clinical Trial

BACKGROUND

Doppler sonography is a type of sonography used for imaging the blood flow in the vessels and heart. This technique uses ultrasound waves with high frequency. In some patient candidates for venous graft, the identification of the suitable vein is not possible with clinical examination.

OBJECTIVE

This study compared the effects of preoperative color Doppler sonography of lower extremity veins on the postoperative outcomes of saphenectomy.

METHODS

This randomized clinical trial was conducted on 100 candidates of an off-pump coronary artery bypass graft (CABG) hospitalized in Afshar Hospital in Yazd in 2015. Patients were divided into two groups: 50 patients in the study group and 50 patients in the control group. Patients in the study group underwent color Doppler sonography of lower extremity veins using the Medison 8000 Live device. Patients in the control group were assessed preoperatively by routine venous examination without undergoing color Doppler sonography. The prepping and draping methods and also the preoperative antibiotics were the same for both groups. The patients were assessed for wound infection, edema, hematoma, and DVT 2 days, 1 week, and 1 month after surgery. Data were analyzed by SPSS version 16 using t-test, Chi-square, and Fisher's exact test.

RESULTS

The length of incision for saphenectomy was 29.20 ± 3.71 cm in the Doppler group and 28.98 ± 3.72 cm in the non-Doppler group with no significant difference between the two groups (p=0.768). The two groups were not significantly different with respect to age, gender, diabetes, hypertension, hyperlipidemia, smoking, and history of peripheral vessels disease, postoperative infection, postoperative organ edema, postoperative hematoma, and postoperative DVT.

CONCLUSION

Preoperative color Doppler sonography of the saphenous vein before saphenectomy has no effect on reducing the postoperative complications, and saphenectomy on the basis of intraoperative examination of the vein course by the surgeon has acceptable consequences.

CLINICAL TRIAL REGISTRATION

The trial was registered at the Thai Clinical Trials Registry (TCTR) (http://www.clinicaltrials.in.th) with the TCTR ID: TCTR20160708001.

FUNDING

The authors received no financial support for the research, authorship, and/or publication of this article.

Vein graft failure: from pathophysiology to clinical outcomes

Occlusive arterial disease is a leading cause of morbidity and mortality worldwide. Aside from balloon angioplasty, bypass graft surgery is the most commonly performed revascularization technique for occlusive arterial disease. Coronary artery bypass graft surgery is performed in patients with left main coronary artery disease and three-vessel coronary disease, whereas peripheral artery bypass graft surgery is used to treat patients with late-stage peripheral artery occlusive disease. The great saphenous veins are commonly used conduits for surgical revascularization; however, they are associated with a high failure rate. Therefore, preservation of vein graft patency is essential for long-term surgical success. With the exception of 'no-touch' techniques and lipid-lowering and antiplatelet (aspirin) therapy, no intervention has hitherto unequivocally proven to be clinically effective in preventing vein graft failure. In this Review, we describe both preclinical and clinical studies evaluating the pathophysiology underlying vein graft failure, and the latest therapeutic options to improve patency for both coronary and peripheral grafts.