Safety of vein bypass grafting to the dorsal pedal artery in diabetic patients with foot infections

National Trends and Outcomes of Pedal Bypass Surgery

OBJECTIVE

The technical demands associated with pedal bypass (PB) surgery place it at risk of underutilization and may be limiting its widespread adoption as a valuable revascularization modality. This study aims to evaluate trends in PB performance, assess its outcomes, and compare its results between high- and low-volume centers.

METHODS

All patients receiving a PB between 2003 and 2023 were identified in the Vascular Quality Initiative (VQI) infrainguinal bypass (IIB) module. The ratio of PB to total IIB performed was calculated for each year and trended over the study period. Centers performing PB were categorized according to their annual PB volume into tertiles of low-volume centers (LVC, <2 PB/year), medium-volume centers (MVC, 2-4 PB/year), and high-volume centers (HVC, >4 PB/year) for comparison. Patient characteristics and outcomes were compared using the χ2 or Fisher exact test as appropriate for categorical variables and the analysis of variance test or Kruskal-Wallis test as appropriate for continuous variables. Cox regression analysis was used to study the association between center volume and the primary outcomes of primary patency, primary-assisted patency, secondary patency, reintervention, amputation, and major adverse limb events (MALE), defined as the composite outcome of amputation and/or reintervention.

RESULTS

A total of 3466 patients received a PB during the study period. The ratio of PB to IIB dropped from 14% to 4% between 2003 and 2023. Primary, primary-assisted, and secondary patency rates were 65%, 76%, and 80%, respectively, and limb salvage rate was 83% at 1 year. Nineteen percent of centers performing IIBs in the VQI did not perform any PBs during the study period. Of the 246 centers performing PBs, 78% were LVC, 15% were MVC, and only 7% were HVC. On Cox regression analysis, HVCs were associated with a lower risk of primary patency loss (hazard ratio [HR], 0.79; 95% confidence interval [CI], 0.66-0.95; P = .010), reintervention (HR, 0.75; 95% CI, 0.60-0.95; P = .016), amputation (HR, 0.77; 95% CI, 0.61-0.98; P = .034), and MALE (HR, 0.78; 95% CI, 0.66-0.93; P = .005) compared with LVCs. No difference in secondary patency between high- and low-volume centers was observed (P = .680).

CONCLUSIONS

The utilization of PB operations experienced a four-fold decrease over the past 20 years, despite favorable patency and limb salvage outcomes. Centers with a higher operative volume in PB achieve better outcomes than LVCs, and accordingly, patients with extensive tibioperoneal disease may benefit from evaluation at centers with documented expertise in PB before resorting to an alternative revascularization modality or a major limb amputation.

Results of the Proliferative Activity’s Analysis of Bifidobacterium Exometabolites in Regard to Hospital Isolates from Patients after Vascular Synthetic Prosthetics Implantation

Problems ofdevelopment of purulent septic complications in vascular surgery during the usage of synthetic prosthetics for shunting and arterial prosthetics are described in this work.Leading factors of development of prosthetic infection are described. Specialties of diagnostics and bacteriological researches wound discharge of wound’s discharge are shown. Tactics of complex treatment of patients with prosthetic infection are presented. This work is dedicated to the experimental researchof proliferative activityof the most encountered opportunistic microorganisms found from the patients of vascular surgery profile with purulent septical complications under the influence of bifidobacteriumbifidium’sexometabolites. Presented results proof the submission of proliferative activity of the most widespread antibiotic-resistant hospital’s isolates under the influence of bifidobacteriumbifidium’sexometabolites.Evaluation during the experiment in vitro of the influence of bifidobacteriumbifidium’sexometabolites on proliferative activityof opportunistic microorganisms.

Effectiveness of revascularisation of the ulcerated foot in patients with diabetes and peripheral artery disease: A systematic review

In patients with diabetes, foot ulceration and peripheral artery disease (PAD), it is often difficult to determine whether, when and how to revascularise the affected lower extremity. The presence of PAD is a major risk factor for non-healing and yet clinical outcomes of revascularisation are not necessarily related to technical success. The International Working Group of the Diabetic Foot updated systematic review on the effectiveness of revascularisation of the ulcerated foot in patients with diabetes and PAD is comprised of 64 studies describing >13 000 patients. Amongst 60 case series and 4 non-randomised controlled studies, we summarised clinically relevant outcomes and found them to be broadly similar between patients treated with open vs endovascular therapy. Following endovascular revascularisation, the 1 year and 2 year limb salvage rates were 80% (IQR 78-82%) and 78% (IQR 75-83%), whereas open therapy was associated with rates of 85% (IQR 80-90%) at 1 year and 87% (IQR 85-88%) at 2 years, however these results were based on a varying combination of studies and cannot therefore be interpreted as cumulative. Overall, wound healing was achieved in a median of 60% of patients (IQR 50-69%) at 1 year in those treated by endovascular or surgical therapy, and the major amputation rate of endovascular vs open therapy was 2% vs 5% at 30 days, 10% vs 9% at 1 year and 13% vs 9% at 2 years. For both strategies, overall mortality was found to be high, with 2% (1-6%) perioperative (or 30 day) mortality, rising sharply to 13% (9-23%) at 1 year, 29% (19-48%) at 2 years and 47% (39-71%) at 5 years. Both the angiosome concept (revascularisation directly to the area of tissue loss via its main feeding artery) or indirect revascularisation through collaterals, appear to be equally effective strategies for restoring perfusion. Overall, the available data do not allow us to recommend one method of revascularisation over the other and more studies are required to determine the best revascularisation approach in diabetic foot ulceration.

Lower limb ischaemia in patients with diabetic foot ulcers and gangrene: recognition, anatomic patterns and revascularization strategies

The confluence of several chronic conditions--in particular ageing, peripheral artery disease, diabetes, and chronic kidney disease--has created a global wave of lower limbs at risk for major amputation. While frequently asymptomatic or not lifestyle limiting, at least 1% of the population has peripheral artery disease of sufficient severity to be limb threatening. To avoid the critical error of failing to diagnose ischaemia, all patients with diabetic foot ulcers and gangrene should routinely undergo physiologic evaluation of foot perfusion. Ankle brachial index is useful when measurable, but may be falsely elevated or not obtainable in as many as 30% of patients with diabetic foot ulcers primarily because of medial calcinosis. Toe pressures and skin perfusion pressures are applicable to such patients.

Effectiveness of revascularization of the ulcerated foot in patients with diabetes and peripheral artery disease: a systematic review

Symptoms or signs of peripheral artery disease (PAD) can be observed in up to 50% of the patients with a diabetic foot ulcer and is a risk factor for poor healing and amputation. In 2012, a multidisciplinary working group of the International Working Group on the Diabetic Foot published a systematic review on the effectiveness of revascularization of the ulcerated foot in patients with diabetes and PAD. This publication is an update of this review and now includes the results of a systematic search for therapies to revascularize the ulcerated foot in patients with diabetes and PAD from 1980 to June 2014. Only clinically relevant outcomes were assessed. The research conformed to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, and Scottish Intercollegiate Guidelines Network methodological scores were assigned. A total of 56 articles were eligible for full-text review. There were no randomized controlled trials, but there were four nonrandomized studies with a control group. The major outcomes following endovascular or open bypass surgery were broadly similar among the studies. Following open surgery, the 1-year limb salvage rates were a median of 85% (interquartile range of 80-90%), and following endovascular revascularization, these rates were 78% (70-89%). At 1-year follow-up, 60% or more of ulcers had healed following revascularization with either open bypass surgery or endovascular techniques. Studies appeared to demonstrate improved rates of limb salvage associated with revascularization compared with the results of conservatively treated patients in the literature. There were insufficient data to recommend one method of revascularization over another. There is a real need for standardized reporting of baseline demographic data, severity of disease and outcome reporting in this group of patients.

Endovascular therapy is effective treatment for focal stenoses in failing infrapopliteal vein grafts

BACKGROUND

To evaluate the efficacy of endovascular therapy for maintaining patency and preserving limbs among patients with failing infrapopliteal bypass grafts.

METHODS

We gathered data from a registry of catheter-based procedures for peripheral artery disease. Of 1554 arteriograms performed from 2006 to 2012, 30 patients had interventions for failing bypass vein grafts to infrapopliteal target vessels. The first intervention for each patient was used in this analysis. Duplex ultrasonography was used within 30 days after intervention and subsequently at 3- to 6-month intervals for graft surveillance.

RESULTS

Interventions were performed for duplex ultrasonography surveillance findings in 21 patients and for symptoms of persistent or recurrent critical limb ischemia in 9 patients. Procedural techniques included cutting balloon angioplasty (83%), conventional balloon angioplasty (7%), and stent placement (10%). Procedural success was achieved in all cases. There were no procedure-related complications, amputations, or deaths within 30 days. By Kaplan-Meier analysis, 37% of the patients were free from graft restenosis at 12 months and 31% were at 24 months. Receiver-operating characteristic analysis indicated that a lesion length of 1.75 cm best predicted freedom from restenosis (C statistic: 0.74). Residual stenosis (P = 0.03), patency without reintervention (P = 0.01), and assisted patency with secondary intervention (P = 0.02) rates were superior for short lesions compared with long lesions. The cohort had acceptable rates of adverse clinical outcomes, with 96% of patients free from amputation at both 12 and 24 months; clinical outcomes were also better in patients with short lesions.

CONCLUSIONS

In this single-center experience with endovascular therapies to treat failing infrapopliteal bypass grafts, rates of limb preservation were high, but the majority of patients developed graft restenosis within 12 months. Grafts with longer stenoses fared poorly by comparison. These data suggest that endovascular interventions to restore or prolong graft patency may be associated with maintained graft patency and that close follow-up with vascular laboratory surveillance is essential.

Healing Diabetic Foot Ulcers Step by Step

Diabetic foot is a leading cause of admission, amputation, and mortality in diabetic patients. A multidisciplinary team approach is highly recommended for the management of patients with foot problems. To heal diabetic foot ulcers, all methods have to be conducted step by step under an efficient program, and all specialists should be well organized also, which was confirmed by the 2 cases described in this article.

Chapter V: Diabetic foot

Ulcerated diabetic foot is a complex problem. Ischaemia, neuropathy and infection are the three pathological components that lead to diabetic foot complications, and they frequently occur together as an aetiologic triad. Neuropathy and ischaemia are the initiating factors, most often together as neuroischaemia, whereas infection is mostly a consequence. The role of peripheral arterial disease in diabetic foot has long been underestimated as typical ischaemic symptoms are less frequent in diabetics with ischaemia than in non-diabetics. Furthermore, the healing of a neuroischaemic ulcer is hampered by microvascular dysfunction. Therefore, the threshold for revascularising neuroischaemic ulcers should be lower than that for purely ischaemic ulcers. Previous guidelines have largely ignored these specific demands related to ulcerated neuroischaemic diabetic feet. Any diabetic foot ulcer should always be considered to have vascular impairment unless otherwise proven. Early referral, non-invasive vascular testing, imaging and intervention are crucial to improve diabetic foot ulcer healing and to prevent amputation. Timing is essential, as the window of opportunity to heal the ulcer and save the leg is easily missed. This chapter underlines the paucity of data on the best way to diagnose and treat these diabetic patients. Most of the studies dealing with neuroischaemic diabetic feet are not comparable in terms of patient populations, interventions or outcome. Therefore, there is an urgent need for a paradigm shift in diabetic foot care; that is, a new approach and classification of diabetics with vascular impairment in regard to clinical practice and research. A multidisciplinary approach needs to implemented systematically with a vascular surgeon as an integrated member. New strategies must be developed and implemented for diabetic foot patients with vascular impairment, to improve healing, to speed up healing rate and to avoid amputation, irrespective of the intervention technology chosen. Focused studies on the value of predictive tests, new treatment modalities as well as selective and targeted strategies are needed. As specific data on ulcerated neuroischaemic diabetic feet are scarce, recommendations are often of low grade.

A systematic review of the effectiveness of revascularization of the ulcerated foot in patients with diabetes and peripheral arterial disease

In several large recent observational studies, peripheral arterial disease (PAD) was present in up to 50% of the patients with a diabetic foot ulcer and was an independent risk factor for amputation. The International Working Group on the Diabetic Foot therefore established a multidisciplinary working group to evaluate the effectiveness of revascularization of the ulcerated foot in patients with diabetes and PAD. A systematic search was performed for therapies to revascularize the ulcerated foot in patients with diabetes and PAD from 1980-June 2010. Only clinically relevant outcomes were assessed. The research conformed to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, and the Scottish Intercollegiate Guidelines Network methodological scores were assigned. A total of 49 papers were eligible for full text review. There were no randomized controlled trials, but there were three nonrandomized studies with a control group. The major outcomes following endovascular or open bypass surgery were broadly similar among the studies. Following open surgery, the 1-year limb salvage rates were a median of 85% (interquartile range of 80-90%), and following endovascular revascularization, these rates were 78% (70.5-85.5%). At 1-year follow-up, 60% or more of ulcers had healed following revascularization with either open bypass surgery or endovascular revascularization. Studies appeared to demonstrate improved rates of limb salvage associated with revascularization compared with the results of medically treated patients in the literature. There were insufficient data to recommend one method of revascularization over another. There is a real need for standardized reporting of baseline demographic data, severity of disease and outcome reporting in this group of patients.

A multidisciplinary diabetic foot ulcer treatment programme significantly improved the outcome in patients with infected diabetic foot ulcers

BACKGROUND

Diabetic foot ulcers (DFUs) superimposed by infection and ischaemia may result in amputation without prompt and adequate management. We investigated whether the diabetic foot ulcer treatment programme (DFUTP) involving immediate debridement within 12 h, flap coverage and/or revascularisation improved the outcome of patients with infected DFUs.

METHOD

Between 2006 and 2009, we randomly enrolled 350 patients in the DFUTP group and compared them with control patients (the non-DFUTP group, n = 386) in Taiwan. Inclusion criteria consisted of infected diabetic foot ulcers with or without ischaemia. The risk factors, dynamics and outcome of amputation and re-amputation were analysed in terms of patient demographics, glycaemic control and infection.

RESULT

The results of logistic regression analyses indicated that risk factors of amputation in both groups were HbA1c (odds ratio (OR) = 1.63, 95% confidence interval (CI) 1.31-2.02) and C reactive protein (OR = 1.12, 95% CI 1.01-1.24). The DFUTP group showed a lower amputation rate than the non-DFUTP group (p = 0.001). The association between the amputation and University of Texas (UT) classification was not statistically significant. The Kaplan-Meier estimate showed that the time to complete recovery of the sugar level in the DFUTP group was faster than in the non-DFUTP group (p = 0.001). For patients at stage D, the hospital stay in the non-DFUTP group was longer than in the DFUTP group (p = 0.014).

CONCLUSION

The DFUTP provides an effective treatment programme for decreasing the amputation rate with infected DFUs. Immediate debridement and flap reconstruction decrease the amputation and re-amputation rate respectively.

A stepwise approach to the surgical management of severe diabetic foot infections

Foot infections are common among diabetic patients with ulceration and are a major cause of hospitalization and lower extremity amputation. Aggressive and emergent surgical intervention is essential in the face of life- or limb-threatening infection to achieve limb salvage and survival. Critical limb ischemia, neuropathy, and an impaired host complicate the treatment of a severe diabetic foot infection. A severe diabetic foot infection carries a 25% risk of major amputation. For this reason, surgery should be coordinated with a well-functioning multidisciplinary team that specializes in diabetic limb preservation. Timing of surgery and strategies employed should be understood and agreed on by both the surgical and medical disciplines managing the diabetic patient with a limb-threatening infection. The overall strategy for surgically managing a severe diabetic foot infection is as follows: the first step is infection control through aggressive and extensive surgical debridement, the second step is a comprehensive vascular assessment with possible vascular surgery and/or endovascular intervention, and the final step is soft tissue and skeletal reconstruction after infection is eradicated to obtain wound closure and limb salvage. A consistent stepwise surgical approach combined with sound surgical principles is paramount for successful management of the severe diabetic foot infection. The authors discuss their stepwise surgical approach to reduce the mortality, morbidity, psychological distress, and length of hospitalization associated with life- or limb-threatening diabetic foot infections.

Review: Peripheral Arterial Disease and Diabetes: A Clinical Update

Peripheral arterial disease is characterized by a gradual reduction in blood to the extremities secondary to atherosclerosis. In diabetes, the pattern of atherosclerotic occlusion typically shows a propensity toward the infrapopliteal vessels. Additionally, impairment of the microcirculation manifests in diminished vasoreactivity and a functional ischemia that is not always correctable with surgery. However, when a nonhealing wound is complicated by peripheral arterial disease, revascularization is paramount to wound healing. Revascularization can be accomplished through traditional bypass surgery or newer endovascular interventions, such as angioplasty and stenting. These less invasive techniques of revascularization offer the advantages of quicker recovery and lower morbidity but durability may be compromised. Ultimately, the choice of revascularization procedure should be based on the clinical characteristics of the atherosclerotic lesion along with the individual patient history.

A stepwise approach to the surgical management of severe diabetic foot infections

Foot infections are common among diabetic patients with ulceration and are a major cause of hospitalization and lower extremity amputation. Aggressive and emergent surgical intervention is essential in the face of life- or limb-threatening infection to achieve limb salvage and survival. Critical limb ischemia, neuropathy, and an impaired host complicate the treatment of a severe diabetic foot infection. A severe diabetic foot infection carries a 25% risk of major amputation. For this reason, surgery should be coordinated with a well-functioning multidisciplinary team that specializes in diabetic limb preservation. Timing of surgery and strategies employed should be understood and agreed on by both the surgical and medical disciplines managing the diabetic patient with a limb-threatening infection. The overall strategy for surgically managing a severe diabetic foot infection is as follows: the first step is infection control through aggressive and extensive surgical debridement, the second step is a comprehensive vascular assessment with possible vascular surgery and/or endovascular intervention, and the final step is soft tissue and skeletal reconstruction after infection is eradicated to obtain wound closure and limb salvage. A consistent stepwise surgical approach combined with sound surgical principles is paramount for successful management of the severe diabetic foot infection. The authors discuss their stepwise surgical approach to reduce the mortality, morbidity, psychological distress, and length of hospitalization associated with life- or limb-threatening diabetic foot infections.

The incidence and risks of failure to heal after lower extremity amputation for the treatment of diabetic neuropathic foot ulcer

The primary goal of this retrospective cohort study was to determine the incidence of failure to heal after lower extremity amputation for the treatment of diabetic neuropathic foot ulcer, and the secondary goal was to identify risk factors associated with the outcome. We evaluated 1775 patients who underwent amputation for the treatment of 5314 neuropathic foot ulcers, and who were treated in a network of wound care centers. We calculated the incidence of failure to heal after the initial amputation, and used generalized estimation equations and generalized linear latent and mixed model regression to evaluate the association of failure to heal by the 20th week of care. The unadjusted incidence of failure to heal was 34.01%, and male sex, number of wounds, wound grade, and adjunct therapy were all significantly associated with failure to heal. With the exception of wound grade, the associations were not significantly affected by the treating wound care center, and a sensitivity analysis showed the results to be resistant to the theoretical influence of an unmeasured potential confounder. These findings should be useful to clinicians treating diabetic neuropathic foot ulcers, and should aid surgeons in the determination of the most appropriate level for lower extremity amputation.

Perfusion through the dorsalis pedis artery for acute limb ischemia secondary to an occlusive arterial cannula during percutaneous cardiopulmonary support

Percutaneous cardiopulmonary support (PCPS) is a powerful resuscitation tool for patients in cardiogenic shock. The femoral artery is generally used for arterial access; however, vascular complications, particularly in atherosclerotic arteries, can occur. Although such complications occur infrequently, they can be fatal. We describe the case of a 75-year-old woman who required extended PCPS for cardiogenic shock secondary to coronary spasm after on-pump beating coronary artery bypass grafting. Limb ischemia occurred because of an occlusive cannula, and distal perfusion with a 20G elastic intravenous catheter inserted into the dorsalis pedis artery resolved the ischemia. The catheter was connected to the side port of an oxygenator and provided distal limb perfusion during PCPS. This technique appears to be useful in treating limb ischemia and may have application in patients with arterial occlusive disease who are dependent on mechanical support.

Timing of Pedal Bypass Failure and Its Impact on the Need for Amputation

Although the utility of dorsalis pedis (DP) bypass for limb ischemia has been well established, the fate of limbs with a failed bypass to the DP artery remains unclear. Data of all patients undergoing DP bypass grafting within a 12-year period from two university hospitals' vascular registries were retrospectively reviewed. Outcomes of early (<30 days) and delayed graft failure (>30 days) were examined. The Student's t-test and chi-squared test were used for univariate analysis; patency rates and patient survival were calculated using the Kaplan-Meier product limit method. Of 1434 DP bypass grafts, 277 (19.3%) failed grafts were identified. Sixty five (4.5%) grafts failed early (within 30 days of surgery) and 212 (14.8%) failed late at a mean time of 15.3 months (range, 1.5-105 months) after initial bypass. Of the 65 limbs with early graft failure, 28 (43.1%) proceeded directly to amputation and 20 underwent additional revascularization attempts, but limb salvage was achieved in only 7 patients; in 45 (69.2%) patients no further revascularizations were attempted. Seventy-four (34.9%) patients with late graft failure underwent redo revascularization. Thirty-nine (52.6%) had their limb saved with graft revision, but 35 patients (47.3%) ultimately lost their limb. In 138 patients with late graft failure (65.1%) no further revascularization attempts were performed. Sixty-two (44.9%) required major amputation. Overall, 49.8% of patients with failed pedal grafts ultimately suffered limb loss. Early graft failure resulted in a significantly higher rate of major amputation that did late graft failure (63.1% vs. 45.8%, respectively; p = 0.015). These results indicate that early occlusion of pedal bypass often leads to immediate major amputation and interventions to maintain graft patency in this setting are often futile. Late failure of pedal bypass is associated with a lower likelihood of amputation because of a higher rate of success of bypass revisions and a lower occurrence of critical ischemia with graft failure.

Anatomic study of the deep plantar arch

A thorough knowledge of the topography and relations of the plantar arteries is necessary for further advances in arterial reconstruction in the foot. Such reconstruction often avoids amputation in cases of arterial trauma in industrial and automobile accidents, as well as in patients with diabetes and severe ischemia of the lower limbs. Although several studies have addressed the anatomy of the arteries of the foot, there is a shortage of recent studies on surgical vascular anatomy. The deep plantar arch was studied in 50 adult cadaveric feet. It was present in all feet and formed from the anastomosis between the deep plantar artery and the deep branch of the lateral plantar artery. The deep plantar artery was predominant in 48% of the specimens (Type I arches) and the deep branch of the lateral plantar artery in 38% (Type II) with the contribution of each being approximately equal in 14% (Type III). The location of the deep plantar arch can be estimated. The distance between the deep plantar arch and each interdigital commissure was relatively consistent between the subjects, averaging 29% of total foot length. The deep plantar arch was located in the middle third of the foot in all specimens, being in the middle II part of this third in 62%. The mean external diameter of the deep branch of lateral plantar artery was 1.7 mm +/- 0.4 mm. The mean external diameter of the deep plantar artery was also 1.7 mm +/- 0.4 mm. We observed a complete superficial plantar arch in only one specimen (2%). Our findings should assist vascular surgeons in estimating the location of the deep plantar arch from the patient's foot length and in providing other data.

Surgical treatment of the infected diabetic foot

Foot infections are common in the diabetic patient. Early recognition, proper assessment, and prompt intervention are vital. A combination of surgery and antibiotics is mandatory in virtually all foot infections. The aim of surgery is 2-fold: first, to control the infection, and second, to attempt to salvage the leg. The eventual goal is always to preserve a functional limb. Foot deformities resulting from surgery may cause reulceration and a high morbidity. The surgical treatment of the infection largely consists of draining of pus and removal of all necrotic and infected tissue. Frequently, revascularization of the foot is needed to save the limb; thus, there must be a close cooperation with the vascular surgical service. The surgeon must have a thorough knowledge of foot anatomy and must be familiar with the defects in wound healing that are caused by diabetes. The outcome of surgery mainly depends on the skill, care, and experience of the surgeon. The best results are achieved within a multidisciplinary setting.

Diagnosis and treatment of diabetic foot infections

Diabetic foot infections frequently cause morbidity, hospitalization, and amputations. Gram-positive cocci, especially staphylococci and also streptococci, are the predominant pathogens. Chronic or previously treated wounds often yield several microbes on culture, including gram-negative bacilli and anaerobes. Optimal culture specimens are wound tissue taken after debridement. Infection of a wound is defined clinically by the presence of purulent discharge or inflammation; systemic signs and symptoms are often lacking. Only infected wounds require antibiotic therapy, and the agents, route, and duration are predicated on the severity of infection. Mild to moderate infections can usually be treated in the outpatient setting with oral agents; severe infections require hospitalization and parenteral therapy. Empirical therapy must cover gram-positive cocci and should be broad spectrum for severe infections. Definitive therapy depends on culture results and the clinical response. Bone infection is particularly difficult to treat and often requires surgery. Several adjuvant agents may be beneficial in some cases.

Vascular evaluation and arterial reconstruction of the diabetic foot

Findings of diminished or absent pulses, pallor on elevation, redness of the foot on lowering of the leg, sluggish refilling of the toe capillaries, and thickened nails or absence of toe hair are consistent with impaired arterial perfusion to the foot. When ischemia is recognized as contributing to pedal ulceration and infection in the diabetic foot, quantitation of its severity may be difficult. Standard clinical evaluation of trophic changes is limited in an infected foot with its accompanying swelling, edema, and erythema. A palpable pedal pulse does not preclude the possibility of the presence of limb-threatening ischemia. Additional non-invasive vascular studies should be undertaken for these patients. Management of the diabetic foot is often a complex clinical problem. However, the principles of care are simple, including correction of systemic factors, such as blood glucose control, cardiovascular risk factor management, and smoking, as well as local factor correction, such as debridement, pressure relief, infection control, and revascularization when indicated. When a patient presents with evidence of infection, adequate drainage and antibiotic therapy are mandatory. The next step should be performed to differentiate the more common neuropathic ulcerations from the truly ischemic ulceration. Symptoms of rest pain or claudication are not often helpful because many of these patients are asymptomatic as a result of the presence of their neuropathy and inactivity. If an infected foot requires debridement or open partial forefoot amputation, observing the wound on a daily base is also important. Once infection is eradicated, there should be prompt signs of healing, including the development of wound granulation within several days. If wounds are not showing signs of prompt healing, arteriography is necessary. Early aggressive drainage, debridement, and local foot amputations combined with liberal use of revascularization results in cumulative limb salvage of 74% at 5 years in high-risk groups. Others report that pedal bypass to the ischemic infected foot is effective and safe as long as infection adequately controlled. These studies strongly suggest that early recognition and aggressive surgical drainage of pedal sepsis followed by surgical revascularization is critical to achieving maximal limb salvage in the high-risk population. Patients who have diabetes present a unique challenge in lower extremity revascularization because of the distal origination of many bypasses, distal distribution of the occlusive disease, and the frequently calcified arterial wall. An aggressive multidisciplinary approach to foot disease associated with diabetes involving the primary care provider, medical specialists, interventional radiology, and podiatric, plastic, and vascular surgeons will provide optimal medical and surgical care. Peripheral vascular disease is highly treatable if intervention is instituted in a timely and collegial fashion.

Diabetic neuropathic foot ulcers: the association of wound size, wound duration, and wound grade on healing

OBJECTIVE

The goal of this study was to evaluate whether simple risk factors can be identified that successfully characterize who will heal and who will not heal among patients who have received standard therapy for diabetic neuropathic foot ulcers.

RESEARCH DESIGN AND METHODS

For this cohort study, we evaluated >31,000 individuals with a diabetic neuropathic foot ulcer seen in the Curative Health Services System. Using multivariate logistic regression, we evaluated the association between wound size, wound duration, wound grade, and other variables and their effect on whether a patient would heal by the 20th week of care.

RESULTS

We demonstrated that wound size, wound duration, and wound grade are all significantly associated with the likelihood of a wound healing by the 20th week of care. In addition, we noted that these associations were not significantly affected by the treating wound care center, whether the unit of analysis was one wound on a patient or all of their wounds, or current adjuvant therapies.

CONCLUSIONS

We have shown that three easy-to-measure risk factors are associated with a wound healing. These results should help clinicians understand the likelihood that a wound will heal and help those conducting clinical investigations to design better trials.

Risks to feet in the top end: outcomes of diabetic foot complications

BACKGROUND

The foot complications of diabetes are severe, disabling, costly and common in the Northern Territory. An understanding of the pathogenesis, the disease spectrum and treatment efficacy, however, is poor. The patterns of disease are documented in the present study; factors associated with good and poor outcomes are identified; and improved management strategies are proposed.

METHODS

All patients presenting to the High Risk Foot Service at Royal Darwin Hospital between March 1997 and March 2000 were included in the present study, and details regarding the status of their feet, their demographics, their treatment and their outcomes were recorded prospectively. Logistic regression analysis was undertaken to determine associations between factors of interest and outcomes of healing and amputation.

RESULTS

One hundred and twenty-six patients were recorded, 41% of whom had neuropathic ulcers and 63% of whom had severe disease at presentation. Two types of diabetic foot pathology were recognized that are not usually classified: acute injury without neuropathy (10%) and deep soft tissue infection alone (9%).Thirty-seven percent and 23% of patients required minor and major amputations, respectively. The total number of hospital bed-days was 5813. Total contact casting was associated with good healing rates in 16 patients. Major amputation was associated with ischaemia, severe disease at presentation and increasing age.

CONCLUSIONS

Patterns of diabetic foot disease which are not commonly recognized are described in the present study; the severity and cost of the problem are documented; and some factors which lead to poor outcome, such as late presentation, are identified. Attention should be paid, through a multidisciplinary team, to timely referral from primary care, patient education, total contact casts and appropriate revascularization.

Never amputate without consultation of a vascular surgeon

Lower limb ischaemia is one of the determinants in the development of diabetic foot ulcers and the most important factor preventing their healing. There are a number of misleading factors masking the presence of atherosclerotic disease and tissue damage; these are reduced inflammatory response to infection, autosympathectomy and mediasclerosis, which all diminish the clinical suspicion of ischaemia. Therefore, adequate assessment of the lower limb circulation should be routinely performed in complicated diabetic foot. This evaluation can often be made with simple methods. In addition to clinical examination ankle/brachial pressure index, systolic toe pressure, plethysmographic pulse volume recordings and simple hand-held Doppler auscultation are most often sufficient to make a decision as to whether angiography is needed or not. Duplex examination can give more profound information on the severity and extent of arterial occlusive disease, but the method is strongly user-dependent. Early vascular consultation is mandatory in diabetic foot work-up and should be undertaken within 2 weeks if a new skin lesion shows no tendency to heal. Long bypass grafting procedures and microvascular free flap techniques have been shown to achieve excellent results in relieving critical leg ischaemia, even in the presence of large foot lesions, and should be used to prevent major amputation. The timing of various procedures is a controversial issue. Feet with small ulcers or restricted dry gangrena can be revascularised first, with minor amputations and local surgery of the ulcer being done thereafter. In the septic neuroischaemic foot, major amputation may be unavailable but if the infection is not immediately life-threatening the infected part of the foot should be drained and debrided properly and left wide open, sometimes with a guillotine amputation in order not to risk the bypass graft, which can be done a couple of days later.

Efficacy of infrainguinal bypass for limb salvage in young diabetic patients

The efficacy of infrainguinal bypass for limb salvage in young diabetic patients has not been well established. The purpose of this study is to determine the intermediate-term results (patency and limb salvage) of infrainguinal revascularization carried out for limb salvage (rest pain or ulceration) in young (<50 years old) diabetic atherosclerotic patients. Thirty-nine bypasses in 31 patients with a mean age of 44 years were retrospectively reviewed. There were no perioperative deaths. Minor or major complications occurred in 23% of cases. By life table analysis, the 18-month primary patency rate was 60+/-11%, assisted primary patency rate was 78+/-9%, and limb salvage rate was 71+/-9%. Most major amputations (five of nine) were required in patients with functional bypasses, either because of persistent infection or failure of wound healing. The presence of severe stenoses (>70%) in all three major named foot vessels (dorsalis pedis, medial and lateral plantar arteries) was associated with a high likelihood of limb loss despite a patent bypass (p<0.05). We could not identify any other factors statistically predictive of thrombosis, amputation, or the need for graft revision. Infrainguinal revascularization in this patient population can be carried out with acceptable limb salvage rates. However, patients should be made aware of the high incidence of amputation regardless of the success of the revascularization procedure, particularly in the presence of severe occlusive disease within the foot.

[Inframalleolar bypass in limb salvage. Late results]

STUDY OBJECTIVE

The objective of this retrospective study was to report the long-term results of distal revascularization at the ankle in patients with critical ischemia.

PATIENTS AND METHODS

From January 1989 to November 1999, 50 inframalleolar bypasses were performed in 49 patients (35 males and 14 females with a mean age of 75 years [range: 51 to 95 years]). Twenty-five patients (50%) were diabetics. All patients presented with critical ischemia of the lower limb. Distal anastomosis was performed at the retromalleolar posterior tibial artery in 28 cases (56%), pedal artery in 20 cases (40%) and distal fibular artery in two cases (4%). Bypasses were performed using a greater saphenous vein (n = 38), a cryopreserved arterial allograft (n = 9), or a PTFE graft (n = 2). A composite graft with greater saphenous vein and arterial allograft was performed in two cases.

RESULTS

There were two early postoperative deaths. One patient presented a blow-out of the distal anastomosis that required bypass ligation and subsequent leg amputation. Early thrombosis of the graft occurred in four cases, leading to major amputation in three cases. No patients were lost to follow-up and mean follow-up was 26.7 months (range: 1 to 86 months). Graft thrombosis occurred in 15 patients and led to amputation in 6 cases. Bypass graft patency rate was 72% and 61% at 1 year and 3 years, respectively, yielding a 80% limb salvage rate at 3 years. The 3-year actuarial survival rate was 53%.

CONCLUSION

Inframalleolar bypasses are a valuable tool in patients with critical ischemia. The lower limb salvage rate is satisfactory in this elderly population. Based on this experience, angiography with good run-off and, when necessary, a surgical approach to verify patency of the arteries at the ankle should always be performed before undertaking a major amputation.

Efficacy of dorsal pedal artery bypass in limb salvage for ischemic heel ulcers

PURPOSE

Although pedal artery bypass has been established as an effective and durable limb salvage procedure, the utility of these bypass grafts in limb salvage, specifically for the difficult problem of heel ulceration, remains undefined.

METHODS

We retrospectively reviewed 432 pedal bypass grafts placed for indications of ischemic gangrene or ulceration isolated to either the forefoot (n = 336) or heel (n = 96). Lesion-healing rates and life-table analysis of survival, patency, and limb salvage were compared for forefoot versus heel lesions. Preoperative angiograms were reviewed to evaluate the influence of an intact pedal arch on heel lesion healing.

RESULTS

Complete healing rates for forefoot and heel lesions were similar (90.5% vs 86.5%, P =.26), with comparable rates of major lower extremity amputation (9.8% vs 9.3%, P =.87). Time to complete healing in the heel lesion group ranged from 13 to 716 days, with a mean of 139 days. Preoperative angiography demonstrated an intact pedal arch in 48.8% of the patients with heel lesions. Healing and graft patency rates in these patients with heel lesions were independent of the presence of an intact arch, with healing rates of 90.2% and 83.7% (P =.38) and 2-year patency rates of 73.4% and 67.0% in complete and incomplete pedal arches, respectively. Comparison of 5-year primary and secondary patency rates between the forefoot and heel lesion groups were essentially identical, with primary rates of 56.9% versus 62.1% (P =.57) and secondary rates of 67.2% versus 60.3% (P =.50), respectively.

CONCLUSION

Bypass grafts to the dorsalis pedis artery provide substantial perfusion to the posterior foot such that the resulting limb salvage and healing rates for revascularized heel lesions is excellent and comparable with those observed for ischemic forefoot pathology.

The benefits of secondary interventions in patients with failing or failed pedal bypass grafts

BACKGROUND

Autogenous bypass grafts to pedal arteries have successfully salvaged limbs and restored function in patients with critical ischemia. The benefits of secondary interventions to save failing or already failed grafts remains uncertain.

METHODS

A retrospective analysis was made of consecutive pedal bypasses performed between 1987 and 1998. Patency and limb salvage by life-table analysis and variables affecting outcome were compared with the log-rank test.

RESULTS

Two hundred thirteen patients, 144 males, 69 females (mean age 68 years, range 30 to 91) underwent pedal bypass grafting in 228 limbs using autogenous vein grafts (nonreversed saphenous vein, n = 190; reversed, n = 15; composite, n = 23). One-hundred fifty-seven patients were diabetic, 34 had renal insufficiency (serum creatinine >2.0), and 14 were on dialysis. Gangrene or ulceration were present in 224 patients, rest pain in 24. Cumulative primary and secondary patency rates were 57% and 67% at 5 years. Limb salvage was 78% at 5 years. Secondary interventions in 46 patients included patch angioplasty/surgical revision (n = 28), thrombectomy (n = 15), thrombolysis (n = 11), and balloon angioplasty (n = 6). Patency in 19 of 26 (73%) failed grafts and in 19 of 20 (95%) failing grafts could be restored initially. Cumulative 2-year patency and limb salvage rates following reinterventions were 36% and 58%, respectively. Patency rates and limb salvage for failed grafts (7%, 44%) were significantly worse than those for failing grafts (81%, 77%; P <0.0001, P <0.05, respectively). All patients with renal insufficiency who underwent reinterventions for failed or failing grafts required major amputation within 1 year (P <0.0001 versus those without renal insufficiency).

CONCLUSION

Autogenous pedal bypass grafts are durable operations with excellent long-term patency and limb salvage rates. Revision of failing grafts has been effective using both endovascular and surgical techniques. Failed grafts have poor long-term patency and moderate limb salvage rates, and our data do not justify secondary procedures to attempt to save failed grafts in patients with renal insufficiency.

Influence of diabetes on revascularisation procedures of the aorta and lower limb arteries: early results

OBJECT

to evaluate the influence of diabetes mellitus on the therapeutic indications and the one-month results in patients with occlusive disease of the aorta and/or lower limbs arteries.

MATERIAL

a retrospective study of fully computerised data of 1003 patients (753 men, 250 women) admitted consecutively to our vascular surgery unit over a 5-year period (1992-1996). Of the total, 169 were diabetics (group I) and 834 were non-diabetics (group II). Sixty-two per cent of patients in group I vs. 40% in group II presented with critical ischaemia or trophic changes (p<0.001).

RESULTS

15.4% of patients in group I vs. 4.1% in group II had primary amputation because of irreversible ischaemia or because arterial reconstruction was impossible. Of those who underwent revascularisation, 80% were infrainguinal in group I vs. 50% in group II. Forty-five per cent of patients in group I and 37% in group II had a percutaneous transluminal angioplasty (PTA) and approximately 3% in both groups had a combination of the two techniques. At one month, patients alive without major amputation numbered 64.4% in group I vs. 93.6% in group II, patients alive with major amputation numbered 26.6% in group I vs. 5.5% in group II, and mortality rates were 8.9% in group I vs. 0.8% in group II (P<0.001).

CONCLUSIONS

the 5-times higher amputation and 10-times higher mortality rates for diabetics compared to non-diabetics call for better collaborative management of diabetics between general practitioners, vascular surgeons, diabetologists and cardiologists. PTA with a 90% initial success rate is indicated for short lesions even in the presence of limited gangrene.

The effects of peripheral vascular disease with osteomyelitis in the diabetic foot

BACKGROUND

Osteomyelitis in the diabetic foot is a difficult problem with multiple etiologies. The effects of peripheral vascular disease, neuropathy, and repetitive trauma all interact to produce complex lesions with exposed bone, surrounding cellulitis, and gangrenous changes.

METHODS

We performed a retrospective study over a 14-year period at a community hospital looking at osteomyelitis in the diabetic foot. We looked at the contributing factors, organisms involved, most common locations, physical findings, and surgical procedures necessary to treat this condition. The purpose of the study was to determine the incidence and effect of peripheral vascular disease in diabetic patients with foot ulcers.

RESULTS

There were a total of 150 patients requiring 278 hospitalizations over the 14-year period who represented 14% of all diabetic admissions. A total of 438 surgical procedures were necessary in these patients, with the most common being debridement (39%) and toe amputation (19%). There were 6 deaths (4%) in this series, and leg amputation was necessary in 21 patients (14%). A vascular bypass was necessary for healing and limb salvage in 36 patients (24%). Most of the bypasses (85%) were with autogenous tissue to the distal leg in order to limit the extent of amputation and to preserve a functional limb.

CONCLUSION

Ischemia is often a contributing factor in the diabetic foot ulcer that must be recognized and treated to avoid prolonged hospitalization, spreading infection, and unnecessary amputation.

Infection in the ischemic lower extremity

Infections in the lower extremity of the patient with ischemia can cover a broad spectrum of different diseases. An understanding of the particular pathophysiologic circumstances in the ischemic extremity can be of great value in understanding the natural history of the disease and the potential complications that may occur. Optimizing blood flow to the extremity by using revascularization techniques is important for any patient with an ischemic lower extremity complicated by infection or ulceration. Infections in the ischemic lower extremity require local débridement and systemic antibiotics. For severe infections, such as necrotizing fasciitis or the fetid foot, more extensive local débridement and even amputation may be required. Fundamentals of managing prosthetic graft infection require removing the infected prosthesis, local wound débridement, and systemic antibiotics while attempting to preserve viability of the lower extremity using autogenous graft reconstruction.

Denatured venous homograft as an arterial substitute in civilian vascular injuries. Thirty months' experience

OBJECTIVES

Autologous saphenous vein (ASV) for arterial reconstruction, in vascular limb injuries is the graft material of choice. Denatured saphenous vein homograft (DSVH), thanks to its characteristics of readily available autologous biological prosthesis, has been proposed as alternative. We report our prospective experience with DSVH employed for arterial reconstruction in civilian limb vascular injuries.

MATERIALS

From January 1994 to June 1996, DSVH was implanted in 16 male patients (pts.) treated for arterial civilian injuries of eight upper limbs and eight lower limbs.

METHODS

In 14 cases it was performed as an interposition graft and in two cases a bypass. We performed a 30-month follow-up and a 20-month mean follow-up.

RESULTS

Four patients had graft thrombosis at the first postoperative week and were submitted to the replacement of the graft with reappearance of distal arterial pulse; one of them had graft failure at the fifth postoperative week and because the necrosis due to extensive soft tissue damage, he was submitted to limb amputation. After 30-months' follow-up we obtained 75% primary patency rate and 93% secondary patency rate.

CONCLUSIONS

In the absence of suitable ASV, DSVH appears to be an interesting alternative for arterial repair in limbs in civilian vascular injuries.

Popliteal-to-distal bypass grafts for limb salvage

From July 1989 to July 1994, a total of 44 popliteal-to-distal artery bypasses were performed in 36 patients (29 men and seven women, mean age 62 +/- 10 years). These procedures accounted for 8.8% of all infrainguinal revascularizations performed during that period. Risk factors included diabetes in 33 patients (92%), smoking in 18 (50%), and coronary artery disease in 15 (42%). Prior to revascularization all patients were at risk of limb loss. Tissue necrosis was present in 31 cases (71%), ulceration in eight cases (18%), and rest pain in five cases (11%). Patency of the femoral and popliteal arteries was confirmed prior to surgery in all cases. Intraoperative percutaneous angioplasty of the superficial femoral artery was performed in three cases. Proximal anastomosis was made to the distal popliteal artery in all cases. A total of 52 distal anastomoses (eight sequential bypasses) were made on the following arteries: posterior tibial artery in 13 cases, anterior tibial artery in eight cases, peroneal artery in six cases, plantar artery in two cases, and dorsalis pedis artery in 21 cases. The greater saphenous vein was used as graft material in 42 cases (95%) and the lesser saphenous vein in two cases (5%). No patient died during hospitalization. Early bypass occlusion occurred in three cases (6.8%) and led to amputation in all cases. Secondary patency and limb salvage rates at 3 years calculated using the actuarial method were 74% and 82% respectively. Bypass thrombosis due to superficial femoral artery deterioration was not observed in any case. The present study indicates that popliteal-to-distal artery bypass is a simple, durable, and low-risk method of lower limb revascularization. Medium-term results are promising and support routine use of popliteal-to-distal artery bypass for limb salvage in patients without significant stenosis of the superficial femoral artery.

Pedal bypass for limb-threatening ischaemia: an 11-year review

Fifty-six patients with limb-threatening ischaemia had pedal revascularization with either autologous vein (n = 39) or sequential composite graft with a 6-mm polytetrafluoroethylene prosthesis and autologous vein (n = 17); 75 per cent had gangrene and skin necrosis and 25 per cent had ischaemic rest pain alone. Twelve grafts occluded within the first week, and resulted in major amputation in eight patients after unsuccessful revision. Two patients required amputation for persistent ischaemia despite a patent bypass. One patient died from bowel perforation (2 per cent). In 47 (84 per cent) of the 56 patients limb and life were preserved. The primary patency rate after 1, 2 and 4 years was 65, 55 and 55 per cent respectively, the secondary patency rate was 71, 62 and 62 per cent, and cumulative limb salvage rates were 77, 71 and 66 per cent. Life-table survival rates during follow-up (median 25 (range 0-112) months) were 89, 78 and 52 per cent respectively after 1, 2 and 4 years. Thirteen of 21 patients who died during follow-up did not require major amputation. Pedal reconstruction with autologous vein provides limb salvage until death in nearly two-thirds of patients with critical limb ischaemia resulting from crural arterial occlusive disease.

Factors influencing the outcome of paramalleolar bypass grafts

Reported patency rates for paramalleolar bypass grafts have varied widely. To determine factors predictive of outcome, we reviewed our experience with 80 consecutive paramalleolar reconstructions in 68 patients performed between December 1986 and May 1995. All procedures were performed for critical limb ischemia defined as nonhealing ulcer or gangrene (n = 72, 90%) and rest pain (n = 8, 10%). Risk factors present were diabetes (n = 52, 65%), hypertension (n = 64, 80%), and history of smoking (n = 57, 71%). Of the 80 bypasses, in situ saphenous vein conduits were used in 39 (49%). In the remainder non-in situ grafts were used including reversed vein (n = 25, 31%), composite vein (n = 11, 14%), polytetrafluoroethylene (PTFE; n = 4, 5%), and composite PTFE/vein (n = 1, 1%). The recipient vessel was the dorsalis pedis artery in 26 procedures (33%), the posterior tibial artery in 32 (40%), the distal anterior tibial artery in 18 (22%), and tarsal or plantar vessels in four (5%). Primary and secondary patency rates were 52% and 68% at 36 months, respectively, by life-table analysis. The limb salvage rate was 86% and patient survival was 56% at 36 months. Secondary patency was significantly higher in diabetic patients than in their nondiabetic counterparts (86% vs. 50% at 36 months, p < 0.03). Similarly, patients undergoing in situ reconstructions had better secondary patency than patients with non-in situ conduits (86% vs. 51% at 36 months, p = 0.03). Diabetic patients tended to be younger (median age 69 years vs. 72 years) and had fewer prior reconstructions (7 [13%] vs. 13 [46%], p < 0.01). Diabetic patients received a higher proportion of in situ reconstructions (54% vs. 39%) but the difference did not achieve statistical significance (p = 0.09). We conclude that the long-term patency for paramalleolar bypass is acceptable but inferior to reported figures for more proximal reconstructions. The factors that most influence patency are the quality of the venous conduit and the presence of diabetes. The improved patency seen in diabetic patients is likely related to the fact that these patients require paramalleolar bypass at an earlier age, are less likely to have had previous reconstructions, and are therefore more likely to have a good quality venous conduit.

Vascular disease of the lower extremities in diabetes mellitus

Vascular disease, neuropathy, and infection act synergistically to cause diabetic foot ulceration. Appropriate care is hindered by misconceptions about microvascular disease. Recent advances and success with extreme distal revascularization combined with surgical management of infection have greatly improved salvage of the diabetic foot. Success is enhanced by a multidisciplinary team approach.

Bypass grafts to the ankle and foot. A personal perspective

Our experience and that of others indicate that the number of very distal bypass operations is growing. From the early 1970s, when we performed a few operations per year, our numbers have increased to 60 to 65 operations annually, about 20% of all infrainguinal open revascularizations. Amputation of one leg leaves a patient, should he survive for a few years, with a second limb that is at substantial risk of infection or gangrene. From over 20 years of experience with thousands of diabetic leg problems and approximately 600 paramalleolar bypasses, the following facts have emerged from our clinical practice. Primary pedal arterial arches are virtually never complete. This alone should not deter the surgeon from attempting paramalleolar bypass grafting. Clinical details such as neuropathy, sepsis, and general medical status and even family support should not be overlooked as "risk factors." The order of frequency for pedal distal anastomotic sites will be anterior tibial/dorsalis pedis, posterior tibial/common plantar artery, lateral plantar artery/medial plantar artery, and lateral tarsal artery. In each case the graft should be placed as proximal as possible on the vessel; tibial outflow should be considered. Use short grafts with distal inflow whenever possible. In the rare instance wherein no pedal target site is available, consider the isolated tibial segment. Failure of a very distal bypass procedure seldom results in an amputation that is more proximal than otherwise would have been required if no bypass were attempted. As a corollary, after sepsis is controlled and all lesions and amputations are healed, failure of the graft may spare the limb from further risk of amputation. In diabetics, the presence of a palpable popliteal pulse and absence of foot pulse are tantamount to identifying the paramalleolar bypass graft candidate. Even the presence of palpable pedal pulses does not exclude patients who could achieve limb salvage with pedal bypass. That determination depends upon an angiogram. Pulsation and flow are not equivalent. Just as the obligations of the surgeon who performs an amputation are not discharged until healing and rehabilitation are complete, likewise, the vascular surgeon's duties after paramalleolar bypass must include a return to the ambulatory status. Careful follow-up, ongoing explicit patient and family education about foot care, and orthotics and shoes will enhance the life and life expectancy of the bipedal patient.

Dorsalis pedis arterial bypass: durable limb salvage for foot ischemia in patients with diabetes mellitus

PURPOSE

Although the technical feasibility of pedal artery bypass for limb salvage is now well established, questions remain about its most appropriate use and its long-term durability.

METHODS

We reviewed our experience over an 8-year period in 367 consecutive patients undergoing 384 vein bypass grafts to the dorsalis pedis for limb salvage.

RESULTS

Ninety-five percent of the patients had diabetes mellitus. Infection complicated ischemia at initial presentation in 55.2% of patients. The preoperative arteriogram demonstrated a patent dorsalis pedis in 362 extremities (92.8%). Four hundred two patients underwent exploration for bypass, including 29 patients without demonstrated arteries on the arteriogram but audible pedal Doppler signals. Successful bypasses were carried out in 357 of 362 cases, where preoperative arteriography demonstrated a patent dorsalis pedis artery (98.6%), 16 of 28 cases explored on the basis of a Doppler signal alone (57%), and 11 of 12 patients where angiographic status was unknown. All procedures were performed with vein: in situ 38.5%, reversed 29%, nonreversed 18%, arm vein 7%, and composite vein 8%. Inflow was taken from the common femoral artery in 34%, superficial femoral or popliteal arteries in 60%, a previously placed graft in 5%, and a tibial artery in 1%. There were seven perioperative deaths (1.8%) and 21 myocardial infarctions (5.4%). Twenty-nine grafts failed within 30 days (7.5%), but 19 were successfully revised. Eight of the 10 failed grafts resulted in major amputation (80%). Over the remaining study period, there were 39 additional graft failures, of which 17 were successfully revised, and 17 additional major amputations. Actuarial primary and secondary patency and limb salvage rates were 68%, 82%, and 87%, respectively, at 5 years' followup. The actuarial patients survival rate was 57% at 5 years. Patency rates were similar for in situ and translocated saphenous vein grafts.

CONCLUSIONS

Dorsalis pedis arterial bypass is an effective limb salvage procedure with long-term durability comparable to distal vein grafts placed into more proximal arteries.

Distal wound complications following pedal bypass: analysis of risk factors

Wound complications of the pedal incision continue to compromise successful limb salvage following aggressive revascularization. Significant distal wound disruption occurred in 14 of 142 (9.8%) patients undergoing pedal bypass with autogenous vein for limb salvage between 1986 and 1993. One hundred forty-two pedal bypass procedures were performed for rest pain in 66 patients and tissue necrosis in 76. Among the 86 men and 56 women, 76% were diabetic and 73% were black. All but eight patients had a history of diabetes and/or tobacco use. Eight wounds were successfully managed with maintenance of patent grafts from 5 to 57 months. Exposure of a patent graft precipitated amputation in three patients, as did graft occlusion in an additional patient. One graft was salvaged by revision to the peroneal artery and one was covered by a local bipedicled flap. Multiple regression analysis identified three factors associated with wound complications at the pedal incision site: diabetes mellitus (p = 0.03), age > 70 years (p = 0.03), and rest pain (p = 0.05). Ancillary techniques ("pie-crusting") to reduce skin tension resulted in no distal wound problems among 15 patients considered to be at greatest risk for wound breakdown. Attention to technique of distal graft tunneling, a wound closure that reduces tension, and control of swelling by avoiding dependency on and use of gentle elastic compression assume crucial importance in minimizing pedal wound complications following pedal bypass.

Microscope-aided pedal bypass is an effective and low-risk operation to salvage the ischemic foot

BACKGROUND

The aim of this study was to determine the current operative risks of the pedal bypass procedure, its durability, and the factors affecting long-term outcome.

METHODS

We prospectively observed 96 patients who consecutively underwent 100 pedal bypasses using autogenous vein grafts for chronic critical ischemia. Of the 100 limbs, 91 had ischemic ulcers or gangrene, and 9 produced rest pain only. Sixty-four patients were diabetic, 21 had renal failure, and 36 had coronary artery disease. Nonreversed saphenous vein grafts were used most frequently (68 translocated, 13 in situ), followed by composite (13) and reversed vein grafts (6). Fifty-two long grafts originated from the iliac or femoral arteries, and 48 short grafts originated from the popliteal or tibial arteries. For the 100 procedures, 102 distal anastomoses were performed--68 to the dorsalis pedis, 8 to the distal posterior tibial, 10 to the common plantar, 2 to the medial plantar, 9 to the lateral plantar, 4 to the lateral tarsal, and 1 to the first dorsal metatarsal arteries--with the aid of an operating microscope.

RESULTS

No patient died during the perioperative period. Two had hemodynamically insignificant myocardial infarctions. Wound complications developed in 12 patients--infection in 7 and hematoma in 5. There were 10 early graft failures, 6 of which could be salvaged, and 96 grafts were patent at dismissal. Mean follow-up was 2.1 years (range 1 month to 6.4 years). Postoperative surveillance identified 33 failed or failing grafts, 16 of which were successfully revised. At 3 years, cumulative primary and secondary patency rates were 60% and 69%, respectively. Factors correlating with increased secondary patency were intraoperative flow rate > or = 50 mL/min (P = 0.004) and diabetes (P < 0.05). Major amputations were performed on 17 limbs. The cumulative foot salvage rate at 3 years was 79%.

CONCLUSION

Pedal bypass is a safe, effective, and durable procedure. It should be considered even for high-risk patients with critical limb ischemia before major amputation is contemplated.