A Comprehensive Review of the Pathogenesis, Diagnosis, and Management of Diabetic Foot Infections.

GENERAL PURPOSE: To review an approach to diabetic foot infections (DFIs), including acute osteomyelitis, while also discussing current practices and the challenges in diagnosis and management. TARGET AUDIENCE: This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and nurses with an interest in skin and wound care. LEARNING OBJECTIVES/OUTCOMES: After participating in this educational activity, the participant will1. Identify the risk factors for developing DFIs.2. Outline diagnostic techniques for assessing DFIs.3. Select the assessment techniques that support a diagnosis of osteomyelitis.4. Choose the appropriate pharmacologic and nonpharmacologic treatment options for patients who have DFIs. ABSTRACT: Diabetic foot ulcers result from a combination of peripheral neuropathy, vascular compromise, and repetitive trauma. Approximately 50% of individuals with diabetic foot ulcers will develop a diabetic foot infection (DFI), and 20% of individuals with a DFI will develop osteomyelitis. Herein, the authors review an approach to DFIs including acute osteomyelitis and discuss current practices and challenges in diagnosis and management.The diagnosis of a skin and soft tissue DFI is based on clinical criteria. A bone biopsy is considered the criterion standard for diagnosis of osteomyelitis; however, biopsy is not always feasible or available. Consequently, diagnosis can be made using a combination of clinical, biochemical, and radiographic findings. X-ray is the recommended imaging modality for initial evaluation; however, because of its lower relative sensitivity, advanced imaging may be used when clinical suspicion remains after negative initial testing.The microbiology of skin and soft tissue DFIs and osteomyelitis is similar. Staphylococcus aureus and other Gram-positive cocci are the most common pathogens identified. Deep cultures are preferred in both DFI and osteomyelitis to identify the etiologic pathogens implicated for targeted antimicrobial therapy. Management also requires a multidisciplinary approach. Surgical debridement in those with deep or severe infections is necessary, and surgical resection of infected bone is curative in cases of osteomyelitis. Finally, appropriate wound care is critical, and management of predisposing factors, such as peripheral neuropathy, peripheral arterial disease, tinea, and edema, aids in recovery and prevention.

Retrospective study of the efficacy of vascularized tissue transfer for treating antibiotic-resistant bacteria-infected wound: Comparison with clean and antibiotic-sensitive bacteria-infected wound.

ABSTRACT: If wounds are infected with bacteria resistant to an empirical antibiotic regimen, effective wound treatment will be delayed. This can delay wound healing and lengthen hospital stays, increasing the costs to patients. Long-term antibiotic use can also result in minor and major complications, such as diarrhea, antibiotic resistance, or life-threatening leukopenia. Multidrug-resistant (MDR) bacteria make wound treatment even more difficult. Traditionally, surgeons thought that adequate infection control should be established before soft tissue coverage. However, wounds infected by MDR do not heal well with this traditional method and there are no optimal treatment guidelines for MDR bacteria-contaminated wounds.We reviewed 203 patients who underwent vascularized flap surgery from 2012 to 2019 to cover wounds. Class IV and I wounds were compared according to the Centers for Disease Control and Prevention classification. Class IV was further classified as antibiotic-resistant (ARB) and antibiotic-sensitive (ASB) bacteria. Wound size, mode, location, pathogens, healing time, and basic demographics were evaluated. Data were compared using Cramer's V and one-way ANOVA or independent t tests.The average healing time was longer in the ARB (19.7 [range 7-44] days) and ASB (17.9 [range 2-36] days) groups than in the Clean group (16.5 [range 7-28] days). Healing time differed in the 3 groups (P = .036). It was longer in the class IV group than in the class I group (P = .01). However, it was not statistically different between the ARB and ASB groups (P = .164).In our study the difference in healing time was small when vascularized tissue transfer was done in ARB-infected wound compared with ASB-infected and clean wound. It is necessary to perform surgery using vascularized tissue for the infected wound of antibiotic-resistant bacteria.

Functional ambulatory status as a potential adjunctive decision-making tool following wound, level of ischemia, and severity of foot infection assessment.

The Society for Vascular Surgery Lower Extremity Threatened Limb Classification System has been developed to stratify amputation risk on the basis of extent of the wound, level of ischemia, and severity of foot infection (WIfI). However, there are no currently validated metrics to assess, grade, and consider functional status, especially ambulatory status, as a major consideration during limb salvage efforts. Therefore, we propose an adjunct to the current WIfI system to include the patient's ambulatory functional status after initial assessment of limb threat. We propose a functional ambulatory score divided into grade 0, ambulation outside the home with or without an assistive device; grade 1, ambulation within the home with or without an assistive device; grade 2, minimal ambulation, limbs used for transfers; and grade 3, a person who is bed-bound. Adding ambulatory function as a supplementary assessment tool can guide clinical decision making to achieve optimal future functional ambulatory outcome, a patient-centered goal as critical as limb preservation. This adjunct may aid limb preservation teams in rapid, effective communication and clinical decision making after initial WIfI assessment. It may also improve efforts toward patient-centered care and functional ambulatory outcome as a primary objective. We suggest a score of functional ambulatory status should be included in future trials of patients with chronic limb-threatening ischemia.

Risk Factors for Hand Wound Infections in People with Diabetes: A Case-control Study.

Hand infection has been associated with increased morbidity in people with diabetes mellitus. PURPOSE: This study was conducted to determine risk factors for hand wound infection in patients with diabetes mellitus. METHODS: A 1:3 matched prospective case-control study was conducted from December 2006 to December 2016. All study patients were consecutively identified through the inpatient records upon admission to the University of the Philippines Manila, Philippine General Hospital (Manila, Philippines), for a hand wound infection necessitating surgical treatment and were followed until hospital discharge, wound healing, or death. Adults (≥18 years old) with diabetes mellitus for at least 6 months and with (study group) or without (control group) a hand wound infection were eligible to participate. Persons with a history of amputation or who were in a chronic debilitated state were excluded. Infection was defined as the presence of inflammation and purulent discharge. Eligible control patients were consecutively recruited from the outpatient clinics and were matched to the study patients by age (± 5 years) and gender. Demographic (eg, age, gender, education, occupation, tobacco use) and clinical data (body mass index [BMI], duration of diabetes, HbA1c levels, wound location and duration, delay in treatment, neuropathy, surgical procedures, length of hospital stay, and presence of arteriovenous [AV] fistula) were collected from patient records and entered into Excel spreadsheets for analysis. Regression analysis was performed and reported as odds ratio (OR) with 95% confidence intervals (CI). Level of significance was set P <.05. RESULTS: Participants included 30 study and 90 control patients. No significant differences between study and control patients were noted in terms of BMI, duration of diabetes, presence of peripheral neuropathy, occupation, or education. Significantly more study patients had elevated HbA1c (86 vs. 30; P = .0001), used tobacco (17 vs. 8; P = .0001), and had an AV fistula (3 vs. 0; P = .015). After multivariate analysis, HbA1c ≥48 mmoL/moL (OR = 18.8; 95% CI: 2.3-153.8; P = .006) and tobacco use (OR = 10.7; 95% CI: 3.5-32.7; P = .0001) were identified as independent risk factors for hand/upper extremity infection. CONCLUSION: Patients with diabetes who smoked or exhibited elevated HbA1c levels were at higher risk of having a hand infection. Further research and efforts to help people with diabetes stop smoking and maintain good glycemic control may help decrease the burden of hand infection.

Evaluation of early wound leakage as a risk factor for prosthetic joint infection.

BACKGROUND AND PURPOSE: Prosthetic joint infection (PJI) is a serious complication resulting from total knee arthroplasty (TKA) or total hip arthroplasty (THA). In this study, patients with a PJI are compared with patients with an uncomplicated postoperative course to identify relevant risk factors for PJI. METHODS: A matched case-control study was performed with patients undergoing fast-track, elective unilateral TKA or THA. The following data were collected: demographics, surgery-related characteristics (perioperative blood loss, use of cement, body temperature), and postoperative characteristics (hematoma formation, wound leakage, blood transfusion, length of stay [LOS]). CONCLUSIONS: When the PJI group was compared with the control group, there was significantly more wound leakage during hospital stay (88% vs. 36%, p = .001) and early wound dressing changes in the first 3 days after surgery (88% vs. 40%, p = .002). Hematoma formation was observed more in the PJI patients group (44% vs. 10%, p = .005). A trend test revealed a significant association between the total number of wound dressing changes and development of PJI (p < .001); 72% of PJI patients had a length of stay of ≥4 days compared with 34% of controls (odds ratio 10.5; 95% CI [2.1-52.3]; p = .004). IMPLICATIONS FOR PRACTICE: Early postoperative wound drainage and hematoma formation directly correlate with PJI. This resulted in a significantly higher number of dressing changes and longer LOS. The nurse practitioner has a central role in postoperative care and is the first to recognize signs of an adverse postoperative clinical course.

The impact of foot infection on infrainguinal bypass outcomes in patients with chronic limb-threatening ischemia.

BACKGROUND: Despite advances in endovascular therapy, infrainguinal bypass continues to play a major role in achieving limb salvage. In this study, we sought to compare outcomes of infrainguinal bypass in patients with limb-threatening ischemia who presented with or without foot infection. METHODS: We conducted a retrospective cohort study of patients who underwent infrainguinal bypass for chronic limb-threatening ischemia at a single institution. End points of interest included long-term mortality, 45-day readmission, postoperative length of stay (LOS), major amputation, and time to wound healing. Multivariable Cox, logistic, and robust regressions were used to model time to event outcomes, readmission rates, and LOS. RESULTS: There were 454 infrainguinal bypass procedures analyzed. Demographics and baseline characteristics were similar, except congestive heart failure and diabetes were more common in the infection group. Presence of foot infection had no impact on mortality (hazard ratio [HR], 0.78; P = .243). Significant predictors of long-term mortality included increasing age, hypoalbuminemia, and congestive heart failure; preoperative use of clopidogrel was protective. Presence of foot infection was an independent predictor of major amputation. In the multiple regression model, the presence of foot infection was independently associated with amputation rate (HR, 2.14; 95% confidence interval, 1.42-3.22; P < .001); use of venous conduit and increasing age and body mass index were protective. Foot infection was an independent predictor of prolonged LOS (mean LOS was 1.54 days longer in patients with vs those without infection; P = .001). Other independent predictors of prolonged LOS included intraoperative blood loss and reoperation; history of continuous preoperative aspirin use and normal baseline renal function and albumin levels were associated with decreased LOS. Readmission was influenced by reoperation (odds ratio [OR], 2.51; P < .001) but not by presence of foot infection (OR, 1.21; P = .349). There was a strong trend for prolonged wound healing time in patients with diabetes (HR, 1.58; P = .05) but not in those with foot infection (OR, 0.74; P = .36). CONCLUSIONS: Among patients requiring infrainguinal bypass for limb-threatening ischemia, infection was more common in patients with diabetes and was a significant predictor of major amputation and prolonged LOS. Infection was not predictive of mortality, wound healing time, or readmission. These findings lend support to the inclusion of infection in risk stratification schemes for patients with chronic limb-threatening ischemia, as recommended in the Society for Vascular Surgery Wound, Ischemia, and foot Infection (WIfI) classification system, because of its adverse impacts on limb salvage.

Improvement of wound healing by regulated oxygen-enriched negative pressure-assisted wound therapy in a rabbit model.

BACKGROUND: Development of drug therapies and other techniques for wound care have resulted in significant improvement of the cure rate and shortening of the healing time for wounds. A modified technique of regulated oxygen-enriched negative pressure-assisted wound therapy (RO-NPT) has been reported. AIM: To evaluate the efficacy and impact of RO-NPT on wound recovery and inflammation. METHODS: Infected wounds were established on 40 adult female white rabbits, which were then randomized to one of four groups: O2 group, regulated negative pressure-assisted wound therapy (RNPT) group, regulated oxygen-enriched negative pressure-assisted wound therapy (RO-NPT) group and healthy control (HC) group. Each day, the O2 group was treated with a constant oxygen supply (1 L/min) to the wound, while the RNPT group was treated with continuous regulated negative pressure (70 ± 5 mmHg) and the RNPT + O2 group was treated with both. The HC group was treated with gauze dressing alone, which was changed every day. Leucocyte count, colony count and wound-healing rate were calculated. Levels of tumour necrosis factor (TNF)-α, interleukin (IL)-1ß and IL-8 were evaluated by ELISA. RESULTS: RO-RNPT significantly decreased bacterial count and TNF-α level, and increased the wound-healing rate. IL-1ß, IL-8 and leucocyte count had a tendency to increase in the early phase of inflammation and a tendency to decrease in the later phase of inflammation in the RO-RNPT group. CONCLUSIONS: RO-NPT therapy assisted wound recovery and inflammation control compared with the RNPT and oxygen-enriched therapies. RO-NPT therapy also increased levels of IL-1ß and IL-8 and attenuated expression of TNF-α in the early phase of inflammation.

Results of One-Stage or Staged Amputations of Lower Limbs Consequent to Critical Limb Ischemia and Infection.

BACKGROUND: Amputations of lower limbs can be conducted as one-stage amputation (OSA) or staged amputation (SA) procedures. The objective of this study was to analyze technical success and mortality rates of both techniques, as well as factors that might influence outcomes in patients with critical limb ischemia (CLI). METHODS: A retrospective study of 185 consecutive patients with CLI who underwent amputations in the period 2004-2011. Primary end points were rates of technical success (healing without dehiscence or reintervention) and mortality. The influence on outcomes of demographic data, clinical status, and comorbidities was also analyzed by logistic regression. RESULTS: A total of 101 SA (91 patients) and 106 OSA (94 patients) were analyzed. SA had proportionally higher success rate (SA 77.2% vs. OSA 66.0%, P = 0.0253), lower perioperative mortality rate (SA, 10.9% vs. OSA, 20.7%, P = 0.0247), and lower 30-day mortality rate (SA, 12.2% vs. OSA, 23.8%, P = 0.0220) in spite of more cases with Rutherford classes 5 and 6 (SA, 87.1% vs. OSA, 72.6%, P = 0.0047), diabetes (71.2% vs. 55.6%, P = 0.0076), and infection (44.5% vs. 28.3%, P = 0.0061). Logistic regression demonstrated that in SA, success was more frequent in patients with diabetes who did not use insulin (P = 0.0072), in those with transfemoral amputations (P = 0.0392), with no coronary artery disease (P = 0.0053), and in foot infection (P = 0.0446), while for OSA success was more frequent in nondiabetic patients (P = 0.0077), limbs without infection (P = 0.0298), amputations at foot level (P = 0.0155), or transfemoral amputations (P = 0.0030). CONCLUSIONS: SA had a higher rate of technical success and lower mortality rates than OSA, even with greater number of patients with diabetes and more severe cases of ischemia and infection. However, prospective studies comparing both techniques are needed for further evidence.

Determinants of midterm functional outcomes, wound healing, and resources used in a hospital-based limb preservation program.

OBJECTIVE: The objective of this study was to assess midterm functional status, wound healing, and in-hospital resource use among a prospective cohort of patients treated in a tertiary hospital, multidisciplinary Center for Limb Preservation. METHODS: Data were prospectively gathered on all consecutive admissions to the Center for Limb Preservation from July 2013 to October 2014 with follow-up data collection through January 2016. Limbs were staged using the Society for Vascular Surgery Wound, Ischemia, and foot Infection (WIfI) threatened limb classification scheme at the time of hospital admission. Patients with nonatherosclerotic vascular disorders, acute limb ischemia, and trauma were excluded. RESULTS: The cohort included 128 patients with 157 threatened limbs; 8 limbs with unstageable disease were excluded. Mean age (±standard deviation [SD]) was 66 (±13) years, and median follow-up duration (interquartile range) was 395 (80-635) days. Fifty percent (n = 64/128) of patients were readmitted at least once, with a readmission rate of 20% within 30 days of the index admission. Mean total number of admissions per patient (±SD) was 1.9 ± 1.2, with mean (±SD) cumulative length of stay (cLOS) of 17.1 (±17.9) days. During follow-up, 25% of limbs required a vascular reintervention, and 45% developed recurrent wounds. There was no difference in the rate of readmission, vascular reintervention, or wound recurrence by initial WIfI stage (P > .05). At the end of the study period, 23 (26%) were alive and nonambulatory; in 20%, functional status was missing. On both univariate and multivariate analysis, end-stage renal disease and prior functional status predicted ability to ambulate independently (P < .05). WIfI stage was associated with major amputation (P = .01) and cLOS (P = .002) but not with time to wound healing. Direct hospital (inpatient) cost per limb saved was significantly higher in stage 4 patients (P < .05 for all time periods). WIfI stage was associated with cumulative in-hospital costs at 1 year and for the overall follow-up period. CONCLUSIONS: Among a population of patients admitted to a tertiary hospital limb preservation service, WIfI stage was predictive of midterm freedom from amputation, cLOS, and hospital costs but not of ambulatory functional status, time to wound healing, or wound recurrence. Patients presenting with limb-threatening conditions require significant inpatient care, have a high frequency of repeated hospitalizations, and are at significant risk for recurrent wounds and leg symptoms at later times. Stage 4 patients require the most intensive care and have the highest initial and aggregate hospital costs per limb saved. However, limb salvage can be achieved in these patients with a dedicated multidisciplinary team approach.

Update on the Role of Infection and Biofilms in Wound Healing: Pathophysiology and Treatment.

BACKGROUND: Chronic wounds, and among these infected diabetic foot ulcers, are a worldwide problem. The poor treatment outcomes result in high healthcare costs, amputations, a decreased quality of life, and an increased mortality. These outcomes are influenced by several factors, including biofilm formation. A biofilm consists of pathogenic bacteria that are encased in an exopolysaccharide layer and communicate through secretion of signaling molecules. Bacteria that live in a biofilm are refractory to host responses and treatment. METHODS: We performed a nonsystematic review of the currently published to-date medical biofilm literature. The review summarizes the evidence of biofilm in chronic wounds, the role of biofilm in wound healing, detection of biofilm, and available antibiofilm treatments. Articles containing basic science and clinical research, as well as systematic reviews, are described and evaluated. The articles have variable levels of evidence. All articles have been peer reviewed and meet the standards of evidence-based medicine. RESULTS: Both animal and human studies have identified biofilm in chronic wounds and have suggested that healing might be influenced by its presence. A promising development in biofilm detection is rapid molecular diagnostics combined with direct microscopy. This technique, rather than classic culture, might support individualized treatment in the near future. A wide range of treatments for chronic wounds also influence biofilm formation. Several agents that specifically target biofilm are currently being researched. CONCLUSIONS: Biofilm formation has a substantial role in chronic wounds. Several diagnostic and therapeutic methods against biofilm are currently being developed.

Validation of the Wound, Ischemia, foot Infection (WIfI) classification system in nondiabetic patients treated by endovascular means for critical limb ischemia.

BACKGROUND: The Society for Vascular Surgery Lower Extremity Guidelines Committee developed the Wound, Ischemia, foot Infection (WIfI) a classification system to predict the amputation risk in patients with critical limb ischemia (CLI). A number of published studies have already evaluated its prognostic value. However, most of the included patients were diabetic, and the validation was done independent of the revascularization procedure. This single-center study evaluated the prognostic value of WIfI stages in nondiabetic patients treated by endovascular means. METHODS: A retrospective analysis was performed of prospectively collected data of nondiabetic patients treated by endovascular means between January 2013 and September 2014. All patients were classified according to their wound status, ischemia index, and extent of foot infection to four classes: very low risk, low risk, moderate risk, and high risk. Comorbidities and vascular lesions for each group were analyzed. The prognostic value of WIfI was analyzed based on the amputation-free survival, overall survival rate, and freedom from amputation at 12 months. RESULTS: Data from 302 CLI patients treated in the study period were reviewed. A total of 219 patients (73%) underwent an endovascular intervention, and among them, 126 nondiabetic patients (58%) were enrolled in this study. Most patients were classified as low risk (33%), and the prevalence of very low-risk, moderate-risk, and very high-risk patients was 23%, 23%, and 21%, respectively. The modified Edifoligide for the Prevention of Infrainguinal Vein Graft Failure (PREVENT III) score was statistically significantly higher in the high-risk group (5.2 ± 2.4) than in the very low-risk, low-risk, and moderate-risk groups (4.3 ± 2.5, 3.5 ± 2.3, 4.5 ± 2.2, respectively; P = .048). One major amputation (1%) was performed during the hospital stay in a high-risk patient. Mean follow-up was 14 ± 8 months. The amputation-free survival at 12 months was 87%, 81%, 81%, and 62%, in the very low-risk, low-risk, moderate risk, and very high-risk groups, respectively (P = .106). The difference was statistically significant between the very low-risk and high-risk groups (hazard ratio, 3.4; 95% confidence interval, 1.1-10.3; P = .029). A similar trend was also observed for 1-year survival between the very low-risk and the high-risk groups (87%, 84%, 81%, 65%; P = .166). The amputation rate during the follow-up time was 0%, 2% (n = 6), 3% (n = 5), and 12% (n = 9) for the very low-risk, low-risk, moderate-risk, and very high-risk groups, respectively (P = .033). CONCLUSIONS: The WIfI classification system predicted the amputation risk and survival in this highly selected group of nondiabetic CLI patients treated by endovascular means, with a statistically significant difference between very low-risk and high-risk patients already at 1 year.

Penetrating shrapnel injuries of the posterior fossa.

BACKGROUND: Gunshot injuries of the posterior fossa are rare and may follow a fatal course. In posterior fossa gunshot injuries, cerebellar hematoma, contusion, obstruction of cerebrospinal fluid (CSF) circulation by the shrapnel, and intracranial hypertension caused by autoregulation loss lead to mortality in the early stage. METHODS: In this study, four cases of patients who underwent surgical intervention after penetrating shrapnel injuries of the pure posterior fossa were evaluated. RESULTS: All of the patients were male; their mean age was 26.5 ± 5 years. The lowest and highest Glasgow Coma Scale scores were 4 and 12, respectively. Neural injury was detected by computed tomography performed after systemic and neurological examination following admission to the emergency service. The shrapnel was found in the cerebellar tissue in three cases and in the fourth ventricle in one case. Following preoperative procedures, surgery was performed with the patient in the prone position. Postoperative monitoring revealed no CSF fistula, meningitis, or hydrocephalus. None of the patients required revision surgery. There were no postoperative mortalities. CONCLUSION: Due to the small volume of the posterior fossa, acute pathologies may lead to rapid neurological deterioration and death. Early surgical intervention and close postoperative follow-up after penetrating shrapnel injuries of the posterior fossa play a significant role in reducing mortality and morbidity.

Burn wound healing and treatment: review and advancements.

Burns are a prevalent and burdensome critical care problem. The priorities of specialized facilities focus on stabilizing the patient, preventing infection, and optimizing functional recovery. Research on burns has generated sustained interest over the past few decades, and several important advancements have resulted in more effective patient stabilization and decreased mortality, especially among young patients and those with burns of intermediate extent. However, for the intensivist, challenges often exist that complicate patient support and stabilization. Furthermore, burn wounds are complex and can present unique difficulties that require late intervention or life-long rehabilitation. In addition to improvements in patient stabilization and care, research in burn wound care has yielded advancements that will continue to improve functional recovery. This article reviews recent advancements in the care of burn patients with a focus on the pathophysiology and treatment of burn wounds.

The Society for Vascular Surgery lower extremity threatened limb classification system based on Wound, Ischemia, and foot Infection (WIfI) correlates with risk of major amputation and time to wound healing.

OBJECTIVE: The purpose of this study was to evaluate whether the new Society for Vascular Surgery (SVS) Wound, Ischemia, and foot Infection (WIfI) classification system correlates with important clinical outcomes for limb salvage and wound healing. METHODS: A total of 201 consecutive patients with threatened limbs treated from 2010 to 2011 in an academic medical center were analyzed. These patients were stratified into clinical stages 1 to 4 on the basis of the SVS WIfI classification. The SVS objective performance goals of major amputation, 1-year amputation-free survival (AFS) rate, and wound healing time (WHT) according to WIfI clinical stages were compared. RESULTS: The mean age was 58 years (79% male, 93% with diabetes). Forty-two patients required major amputation (21%); 159 (78%) had limb salvage. The amputation group had a significantly higher prevalence of advanced stage 4 patients (P < .001), whereas the limb salvage group presented predominantly as stages 1 to 3. Patients in clinical stages 3 and 4 had a significantly higher incidence of amputation (P < .001), decreased AFS (P < .001), and delayed WHT (P < .002) compared with those in stages 1 and 2. Among patients presenting with stage 3, primarily as a result of wound and ischemia grades, revascularization resulted in accelerated WHT (P = .008). CONCLUSIONS: These data support the underlying concept of the SVS WIfI, that an appropriate classification system correlates with important clinical outcomes for limb salvage and wound healing. As the clinical stage progresses, the risk of major amputation increases, 1-year AFS declines, and WHT is prolonged. We further demonstrated benefit of revascularization to improve WHT in selected patients, especially those in stage 3. Future efforts are warranted to incorporate the SVS WIfI classification into clinical decision-making algorithms in conjunction with a comorbidity index and anatomic classification.

[Water-filtered infrared-A (wIRA) promotes wound healing]. / Wassergefiltertes Infrarot A (wIRA) hilft Wunden heilen.

Water-filtered infrared-A (wIRA) is a special form of heat radiation with high tissue penetration and low thermal load to the skin surface which promotes the healing of acute and chronic wounds both by thermal and thermic as well as by non-thermal and non-thermic effects. Water-filtered infrared-A increases tissue temperature (+ 2.7 °C at a tissue depth of 2 cm), tissue oxygen partial pressure (+ 32 % at a tissue depth of 2 cm) and tissue perfusion. These three factors are decisive for a sufficient supply of tissue with energy and oxygen and consequently also for wound healing and infection defense. Water-filtered infrared-A promotes normal as well as disturbed wound healing by diminishing inflammation and exudation, by promotion of infection defense and regeneration, and by alleviation of pain. These effects have been proven in a total of seven prospective studies (of these six randomized controlled studies) with most of the effects having an evidence level of Ia or Ib. The additional cases of complicated courses of wound healing presented in this article illustrate the proven effects of wIRA. Not only in the 6 presented cases wIRA turned the complicated courses of wound healing for the better and facilitated the healing of the wounds after varying total times of irradiation (in the 6 cases 51-550 h) and after variable times of wound care and mostly after transplantation of split skin grafts. In complicated courses of wound healing wIRA does not replace consultation and, when indicated, treatment by an experienced plastic surgeon and by a surgeon specialized in septic surgery. With these limitations wIRA can be recommended as a valuable complement for the treatment of acute as well as of chronic wounds.

Facts that every vascular surgeon needs to know about the diabetic foot.

This paper describes important aspects of the diabetic foot which the vascular surgeon needs to understand to efficiently manage the diabetic foot. Firstly, it emphasises the three main pathologies which come together in the diabetic foot, namely neuropathy, ischemia and immunopathy, the latter predisposing to infection. As a result of neuropathy, the signs and symptoms of tissue breakdown, infection and ischemia may be minimal. Nevertheless the pathology emanating from such clinical events proceeds rapidly without the body being aware of it and the end stage of tissue death and necrosis is quickly reached. It is important to have a prompt system of evaluation and intervention to prevent the rapid progression to necrosis. Thus, secondly, the paper describes a simple rapid assessment of the diabetic foot, which comprises inspection, palpation and sensory testing and leads on to a modern classification and staging of the diabetic foot. This classifies six subdivisions of the diabetic foot: foot with neuropathic ulceration, Charcot foot, neuroischemic foot, critically ischemic foot, acutely ischemic foot and renal ischemic foot and six stages in the natural history of each of these subdivisions: normal foot, high risk foot, ulcerated foot, infected foot, necrotic foot and unsalvageable foot. Thirdly, it describes modern management of the diabetic foot, emphazising wound care and revascularization within the context of a multidisciplinary care team that provides integrated care focused in a diabetic foot clinic, to which patients with diabetes should have easy and rapid access. Members of the team include podiatrist, nurse, orthotist, physician, radiologist and surgeons.

When does hip fracture surgery fail?

INTRODUCTION: Hip fractures remain the most common orthopaedic injury requiring hospital admission. Failed surgery for any cause carries a higher morbidity, mortality, and healthcare-related cost. The aims of this study were to determine risk factors for surgical complications of hip fracture surgery, when they occurred and their effect on mortality. PATIENTS AND METHODS: From a prospectively collected consecutive database of 795 hip fractures admitted between July 2007 and June 2008, all surgical and non-surgical complications were identified as well as re-operation for any cause and mortality in the 4 years since surgery. RESULTS: Fifty-five (6.9%) patients were found to have developed a surgical complication requiring further intervention. Risk factors included younger age, smoking and cannulated screw fixation. Cannulated screw fixation was associated with a 30.9% rate of re-operation. Post-operative medical complication occurred in 21.8%. It was associated with a 78.5% mortality at 4 years with a median time to mortality of 58 days (95% CI 0-120 days). CONCLUSIONS: Mechanical failure was the most common reason for cannulated screw re-operation. Hip hemiarthroplasty most commonly failed by infection. Inter-trochanteric and sub-trochanteric fracture fixation had very low failure rates. Post-operative medical complications, but not surgical complications, were associated with a higher mortality rate.

The effects of pH on wound healing, biofilms, and antimicrobial efficacy.

It is known that pH has a role to play in wound healing. In particular, pH has been shown to affect matrix metalloproteinase activity, tissue inhibitors of matrix metalloproteinases activity, fibroblast activity, keratinocyte proliferation, microbial proliferation, and also immunological responses in a wound; the patient's defense mechanisms change the local pH of a wound to effect microorganism invasion and proliferation; this pH change has been found to affect the performance of antimicrobials, and therefore the efficacy in biological environments directly relevant to wound healing. Based on the available body of scientific evidence to date, it is clear that pH has a role to play in both the healing of and treatment of chronic and acute wounds. It is the purpose of this review to evaluate the published knowledge base that concerns the effect of pH changes, the role it plays in wound healing and biofilm formation, and how it can affect treatment efficacy and wound management strategies.

Deficient cytokine expression and neutrophil oxidative burst contribute to impaired cutaneous wound healing in diabetic, biofilm-containing chronic wounds.

Diabetic patients exhibit dysregulated inflammatory and immune responses that predispose them to chronic wound infections and the threat of limb loss. The molecular underpinnings responsible for this have not been well elucidated, particularly in the setting of wound biofilms. This study evaluates host responses in biofilm-impaired wounds using the TallyHo mouse, a clinically relevant polygenic model of type 2 diabetes. No differences in cytokine or Toll-like receptor (TLR) expression were noted in unwounded skin or noninoculated wounds of diabetic and wild-type mice. However, diabetic biofilm-containing wounds had significantly less TLR 2, TLR 4, interleukin-1ß, and tumor necrosis factor-α expression than wild-type wounds with biofilm (all p < 0.001). Both groups had similar bacterial burden and neutrophil infiltration after development of biofilms at 3 days postwounding, but diabetic wounds had significantly less neutrophil oxidative burst activity. This translated into a log-fold greater bacterial burden and significant delay of wound epithelization for biofilm-impaired diabetic wounds at 10 days postwounding. These results suggest that impaired recognition of bacterial infection via the TLR pathway leading to inadequate cytokine stimulation of antimicrobial host responses may represent a potential mechanism underlying diabetic susceptibility to wound infection and ulceration.