Mortality and hospitalization in patients after amputation: a comparison between patients with and without diabetes

Multimodal therapy as an algorithm to limb salvage in diabetic patients with large heel ulcers

In many series of diabetic foot ulcer care, heel ulcers greater than 4 cm across have been identified as an independent predictor of limb loss. Therefore, we set out to pursue the most aggressive limb salvage algorithm in patients with heel ulcers greater than 4 cm in diameter. Over 5 years, we identified 21 patients, 39-84 years of age, all with diabetes mellitus, with heel ulcers greater than 4 cm in diameter and had magnetic resonance imaging or bone scan evidence of osteomyelitis. Seven of the 21 patients had end-stage renal disease defined as being haemodialysis dependent. All patients had ankle brachial indices <0·4 or monophasic pulse volume recordings. All patients underwent distal bypass surgery with vein. After adequate perfusion was obtained, all patients underwent partial calcanectomy and intra-operative negative pressure wound therapy (NPWT) placement. This was followed by treatment with recombinant platelet-derived growth factor (PDGF). One patient underwent amputation during the healing process secondary to ongoing sepsis. Twenty of 21 patients healed acutely (within 6 months). Three of 20 patients went on to subsequent below knee amputation within 12 months of healing primarily. At 2 years, 12 of 21 (57%) were ambulating independently, 1 of 21 was dead, 4 of 21 had undergone amputation, 4 (19%) had limbs that were intact but were not ambulating. A total limb salvage rate of 76% at 2 years mirrored the secondary patency rates, with 100% follow up. Heel ulcers require multimodality therapy if they are going to have any chance to heal. We believe the algorithm presented allows for the required revascularisation and a modulation of the heel ulcer microenvironment by augmenting the microcirculation through NPWT, and improving the proliferative capacity with PDGF.

Developing and validating a risk score for lower-extremity amputation in patients hospitalized for a diabetic foot infection

OBJECTIVE

Diabetic foot infection is the predominant predisposing factor to nontraumatic lower-extremity amputation (LEA), but few studies have investigated which specific risk factors are most associated with LEA. We sought to develop and validate a risk score to aid in the early identification of patients hospitalized for diabetic foot infection who are at highest risk of LEA.

RESEARCH DESIGN AND METHODS

Using a large, clinical research database (CareFusion), we identified patients hospitalized at 97 hospitals in the U.S. between 2003 and 2007 for culture-documented diabetic foot infection. Candidate risk factors for LEA included demographic data, clinical presentation, chronic diseases, and recent previous hospitalization. We fit a logistic regression model using 75% of the population and converted the model coefficients to a numeric risk score. We then validated the score using the remaining 25% of patients.

RESULTS

Among 3,018 eligible patients, 21.4% underwent an LEA. The risk factors most highly associated with LEA (P < 0.0001) were surgical site infection, vasculopathy, previous LEA, and a white blood cell count >11,000 per mm(3). The model showed good discrimination (c-statistic 0.76) and excellent calibration (Hosmer-Lemeshow, P = 0.63). The risk score stratified patients into five groups, demonstrating a graded relation to LEA risk (P < 0.0001). The LEA rates (derivation and validation cohorts) were 0% for patients with a score of 0 and ~50% for those with a score of ≥21.

CONCLUSIONS

Using a large, hospitalized population, we developed and validated a risk score that seems to accurately stratify the risk of LEA among patients hospitalized for a diabetic foot infection. This score may help to identify high-risk patients upon admission.

Measuring the accuracy of different ways to identify the 'at-risk' foot in routine clinical practice

AIMS

We aimed to identify which individual risk factors best predict foot ulceration in routine clinical practice and whether an integrated clinical tool is a better screening tool for future foot ulceration.

METHODS

Routinely collected clinical information on foot and general diabetes indicators were recorded on the regional diabetes electronic register. Follow-up data on foot ulceration were collected from the same electronic record, the local multidisciplinary foot clinic and community and hospital podiatry paper records. Data were electronically linked to see which criteria best predicted future foot ulceration.

RESULTS

Foot risk scores were recorded on 3719 patients (44% female, mean age 59±15years) across community and hospital clinics. Overall, 851 (22.9%) had insensitivity to monofilaments, in 629 (17.2%) both pulses were absent and 184 (4.9%) had a prior ulcer. In multivariate analysis, the strongest predictors of foot ulceration were prior ulcer, insulin treatment, absent monofilaments, structural abnormality and proteinuria and retinopathy. The sensitivity of predicting foot ulceration was 52% for prior ulcer, 61% for absent monofilaments, 75% for 'high risk' on an integrated risk score and 91% for high and moderate risk combined. The corresponding specificities were 99, 81, 89 and 61%. Positive likelihood ratio was 52 for prior ulcer and 6.8 for foot risk, with negative likelihood ratios of 0.48 and 0.15, respectively.

CONCLUSIONS

Integrated foot risk scores are more sensitive than individual clinical criteria in predicting future foot ulceration and are likely to be better screening tools, where excluding false negative results is of paramount importance.

Assessing the long-term outcomes of minor lower limb amputations: a 5-year study

Our aim was to assess the long-term outcome for minor forefoot amputations. A retrospective study of 126 patients who had such amputations between 1999 and 2004 was performed. Patients were divided into 2 groups, diabetic (group A: 79 patients) and nondiabetic (group B: 47 patients). Angiograms were requested in 45 patients in group A compared with 31 patients in group B (P = ·77). In group A, 11 patients underwent further ipsilateral amputations compared with 30 patients in group B (P = ·02.). The 2 groups were equally likely to have vascular reconstruction (35% vs 37%). The overall 5-year mortality was 27%, with 58% of deaths occurring within the first year. This study shows that foot amputees have high mortality and reintervention rates. Adequate utilization of vascular services, extra vigilance in the prevention of complications, and risk factor modifications are required to improve postoperative outcomes.

Limb salvage in severe diabetic foot infection

BACKGROUND

The purpose of our study was to determine the efficacy of a management algorithm that includes negative pressure wound therapy (NPWT) in diabetic feet with limb-threatening infection.

MATERIALS AND METHODS

Forty-five septic diabetic feet were treated with NPWT between 2006 and 2008. After emergent abscess evacuation, early vascular intervention was performed if necessary. Debridement, with or without partial foot amputation, was followed by NPWT. Wound progress was measured using a digital scanner. A limb was considered salvaged if complete healing was achieved without any or with minor amputation through or below the ankle. The mean followup after complete wound healing was 17 (range, 6 to 35) months.

RESULTS

Thirty-two cases (71%) were infected with two or more organisms. Negative pressure wound therapy was applied for 26.2±14.3 days. The median time to achieve more than 75% wound area granulation was 23 (range, 4 to 55) days and 104 (range, 38 to 255) days to complete wound healing. Successful limb salvage was achieved in 44 cases (98%); 14 (31%) without any amputation and 30 (67%) with partial foot amputations. Total number of operations per limb was 2.4±1.3. One case of repeated infection and necrosis was managed with a transtibial amputation. There were no complications associated with NPWT.

CONCLUSION

This study provides the outcome of a management algorithm which includes NPWT in salvaging severely infected diabetic feet. With emergent evacuation of abscess, early vascular intervention and appropriate debridement, NPWT can be a useful adjunct to the management of limb-threatening diabetic foot infections.

Fewer major amputations among individuals with diabetes in Finland in 1997-2007: a population-based study

OBJECTIVE

Complications occur in diabetes despite rigorous efforts to control risk factors. Since 2000, the National Development Programme for the Prevention and Care of Diabetes has worked to halve the incidence of amputations in 10 years. Here we evaluate the impact of the efforts undertaken by analyzing the major amputations done in 1997-2007.

RESEARCH DESIGN AND METHODS

All individuals with diabetes (n = 396,317) were identified from comprehensive national databases. Data on the first major amputations (n = 9,481) performed for diabetic and nondiabetic individuals were obtained from the National Hospital Discharge Register.

RESULTS

The relative risk for the first major amputation was 7.4 (95% CI 7.2-7.7) among the diabetic versus the nondiabetic population. The standardized incidence of the first major amputation decreased among the diabetic and nondiabetic populations (48.8 and 25.2% relative risk reduction, respectively) over 11 years, and the time from the registration of diabetes to the first major amputation was significantly longer, on average 1.2 years more. The cumulative five-year postamputation mortality among diabetic individuals was 78.7%.

CONCLUSIONS

In our nationwide diabetes database, the duration from the registration of diabetes to the first major amputation increased, and the incidence of major amputations decreased almost 50% in 11 years. Approximately half of this change was due to the increasing size of the diabetic population. The risk for major amputation is more than sevenfold that among the nondiabetic population. These results pose a continuous challenge to improve diabetes care.

Self-reported use of complementary and alternative medicine (CAM) products in topical treatment of diabetic foot disorders by diabetic patients in Jeddah, Western Saudi Arabia

Background

There is little published on current Saudi diabetic patients' practices when they are exposed to foot disorders such as open wound, ulcer, and skin cracks. These factors are usually influenced by local culture and communities beliefs. The aim of the current study was to identify the pattern of patients' use of CAM products in dealing with diabetic foot disorders topically in a group of diabetic patients.

Findings

A Cross-sectional descriptive study of a representative cohort of diabetic patients living in Jeddah, Saudi Arabia was designed. A pre-designed questionnaire to identify local diabetics' practices in dealing topically with foot disorders including open wound, chronic ulcer, and skin cracks was designed. Questionnaire was administered by a group of trained nutrition female students to diabetics face to face living in their neighborhood. A total of 1634 Saudi diabetics were interviewed. Foot disorders occurred in approximately two thirds of the respondents 1006 (61.6%). Out of the 1006 patients who had foot disorders, 653 reported trying some sort of treatment as 307 patients (47.1%) used conventional topical medical treatment alone, 142 (21.7%) used CAM products alone, and 204 (31.2%) used both treatments. The most commonly used CAM product by the patients was Honey (56.6%) followed by Commiphora Molmol (Myrrh) in (37.4%) and Nigellia Sativa (Black seed) in (35.1%). The least to be used was Lawsonia inermis (Henna) in (12.1%). Ten common natural preparations used topically to treat diabetic foot disorders were also identified.

Conclusions

The use of CAM products in topical treatment of diabetic foot disorders is fairly common among Saudi diabetic patients. Honey headed the list as a solo topical preparation or in combination with other herbs namely black seeds and myrrh. The efficacy of the most common products needs further research.

Association between glycated haemoglobin and the risk of lower extremity amputation in patients with diabetes mellitus-review and meta-analysis

AIMS/HYPOTHESIS

Diabetes increases the risk of lower extremity amputation (LEA). Although epidemiological studies report positive associations between glycaemia and LEA, the magnitude of the risk is not adequately quantified and clinical trials to date have not provided conclusive evidence about glucose lowering and LEA risk. We synthesised the available prospective epidemiological data on the association between glycaemia measured by HbA(1c) and the risk of LEA in individuals with diabetes.

METHODS

We searched electronic databases and reference lists of relevant articles. We considered prospective epidemiological studies that had measured HbA(1c) level and assessed LEA as an outcome among diabetic individuals without acute foot ulcerations or previous history of amputation. Of 2,548 citations identified, we included 14 studies comprising 94,640 participants and 1,227 LEA cases. We abstracted data using standardised forms and obtained data from investigators when required. Data included characteristics of study populations, HbA(1c) assay methods, outcome and covariates. Study-specific relative risk estimates were pooled using random-effects model meta-analysis; heterogeneity was explored with meta-regression analyses.

RESULTS

The overall RR for LEA was 1.26 (95% CI 1.16-1.36) for each percentage point increase in HbA(1c). There was considerable heterogeneity across studies (I (2) 76%, 67-86%; p < 0.001), which was not accounted for by recorded study characteristics. The estimated RR was 1.44 (95% CI 1.25-1.65) for type 2 diabetes and 1.18 (95% CI 1.02-1.38) for type 1 diabetes; however, the difference was not statistically significant (p = 0.09). We found no strong evidence for publication bias.

CONCLUSIONS/INTERPRETATION

There is a substantial increase in risk of LEA associated with glycaemia in individuals with diabetes. In the absence of conclusive evidence from trials, this paper provides further epidemiological support for glucose-lowering as a strategy to reduce amputation in a population without acute foot ulceration or former amputation; it also provides disease modellers with estimates to assess the overall burden of hyperglycaemia.

In-Hospital Complications and Mortality Following Major Lower Extremity Amputations in a Series of Predominantly Diabetic Patients

The purpose of this study was to analyze the outcomes of major lower extremity amputations (MLEAs) in a series, including diabetic patients, with the aim to study whether diabetes mellitus is a risk factor of in-hospital mortality and perioperative complications. A retrospective analysis of 283 MLEAs (221 of these patients were diabetic and 62 were nondiabetic) performed between January 1, 1998, and December 31, 2008, at the General Surgery Department and Diabetic Foot Unit of La Paloma Hospital in Las Palmas de Gran Canaria (Canary Islands) was done. The significant risk factors of mortality were >" xbd="324" xhg="301" ybd="1481" yhg="1446"/>75 years of age (odds ratio [OR] = 4.1, 95% confidence interval [CI] = 1.4-11.7), postoperative cardiac complications (OR = 12.3, 95% CI = 3.7-40.2) and postoperative respiratory complications (OR = 3.8, 95% CI = 1.0-13.3). No statistically significant risk factors were found related to the presence of systemic and wound-related complications. In diabetic patients, the significant risk factors of mortality were postoperative cardiological complications (OR = 13.6, 95% CI = 3.1-59.6), postoperative respiratory complications (OR = 5.9, 95% CI = 1.0-35.5), and first episode of amputation (OR = 5.9, 95% CI = 1.4-24.3). There were no statistically significant differences in the outcome of major amputations between diabetic and nondiabetic patients. Hospital stay was significantly longer in diabetic patients ( P < .01) though when the patients with diabetic foot infections were excluded, this difference was not found.

Review: The varied attractions of the diabetic foot

Various advances have been seen in the management of the diabetic foot. In some areas the rate of diabetes-related major amputations is declining. Duloxetine, pregabalin, venlafaxine and oxycodone are all well proven to help alleviate the pain of diabetic neuropathy. Negative pressure wound therapy has been shown to accelerate the healing of foot ulcers. New antibiotic policies designed to reduce Clostridium difficile and methicillin-resistant Staphylococcus aureus (MRSA) infections focus on narrow spectrum short duration antibiotics, and 80% of osteomyelitis can be successfully treated without surgery. Foot screening identifies patients who will ulcerate, with high-risk patients being up to 83 times more likely to ulcerate than low-risk patients. The ‘holiday foot’ and distal peripheral vascular disease remain as major risk factors for foot ulcer development and non-healing. The diabetic foot provides many interesting and varied challenges for the interested clinician.

Br J Diabetes Vasc Dis 2009;9:155—159

Decreasing amputation rates in patients with diabetes-a population-based study

AIMS

To assess the changing rate of amputation in patients with diabetes over a 7-year period.

METHODS

All patients undergoing lower extremity amputation in Tayside, Scotland between 1 January 2000 and 31 December 2006 were identified. Temporal linkage of cases to the diabetes database was used to ascertain which amputations were in patients with diabetes.

RESULTS

The incidence of major amputations fell from 5.1 [95% confidence interval (CI) 3.8-6.4] to 2.9 (95% CI 1.9-3.8) per 1000 patients with diabetes (P < 0.05). There is a clear linear trend in the adjusted incidence of major amputation (P = 0.023 and 0.027 for age- and sex-adjusted, and duration- and sex-adjusted incidences, respectively). The adjusted incidence of total amputations followed decreased linear regression trend over the whole study period when adjusted for age and sex or diabetes duration and sex (P = 0.002).

CONCLUSIONS

There has been a significant reduction in the incidence of major lower extremity amputation in patients with diabetes over the 7-year period.

Improving limb salvage rate in diabetic patients with critical leg ischaemia using a multidisciplinary approach

BACKGROUND

Diabetic patients are more likely to develop critical leg ischaemia (CLI) and subsequently major amputation than the general population. Major amputation rate in this group is reported to be high compared with non-diabetic patients with a devastating outcome.

AIM

The aim of this study was to assess the impact of a multidisciplinary approach on the major amputation rate in diabetic patients with CLI suitable for surgical or radiological revascularisation.

METHODS

A retrospective analysis of data of all diabetic patients with CLI presenting to a one-stop multidisciplinary clinic between December 2003 and May 2006 was performed. The multidisciplinary team included a vascular surgeon, diabetologist, podiatrist, tissue viability nurse, interventional radiologist and a radiology coordinator. Peripheral vascular disease was assessed by history taking, clinical examination, ankle brachial pressure index, Doppler arterial waveform analysis and transcutaneous oxygen tension. Duplex scan and magnetic resonance angiography were performed in selected patients. Based on the available information, suitable patients were offered percutaneous transluminal angioplasty (PTA), surgical arterial reconstruction (SAR) or both (hybrid arterial reconstruction).

RESULTS

Three hundred and twelve diabetic patients with CLI were suitable for revascularisation. Eighty-two per cent underwent PTA while 18% underwent SAR. Thirteen threatened grafts were detected during follow-up and early intervention was performed as required. Major amputation rate among the study group was 4.1%.

CONCLUSION

Multidisciplinary approach improves the care of diabetic patients with CLI. Close follow-up and early intervention in dedicated centres improve limb salvage rates in this group of high-risk patients.

Internal pedal amputations

Internal pedal amputation consists of resection of the metatarsals, midtarsal bones, or talus with preservation of the toes and soft-tissue envelope. Although used in the past for the treatment of tuberculosis within the pedal skeleton, internal pedal amputations have become almost forgotten, historical procedures. However, following internal pedal amputations of a diabetic patient, the foot undergoes significant contracture that results in a stable, functional, foreshortened residual foot capable of being protected in custom-molded shoe gear with external or in-shoe orthoses. The author presents the surgical approach and postoperative treatment regime for each form of internal pedal amputation, as well as "pearls" for success.

Mortality, causes of death and associated risk factors in a cohort of diabetic patients after lower-extremity amputation: a 6.5-year follow-up study in Taiwan

BACKGROUND

To determine the mortality, causes of death and associated risk factors in Taiwanese diabetic patients after lower-extremity amputation (LEA).

METHODS

A total of 358 diabetic patients (191 men and 167 women, aged 66.6+/-10.3 years) after LEA from the Taiwanese cohort of 778 cases previously recruited in the multinational Global Lower Extremity Amputation Study were followed. Risk factors included age, sex, smoking, body mass index (BMI), hypertension, systolic (SBP) and diastolic blood pressure (DBP), and LEA level. Mortality was ascertained from the National Death Registry.

RESULTS

With a follow-up period of up to 6.5 (median: 4.0) years and 1239.17 patient-years, 214 patients died. Crude mortality rate was 172.7 per 1000 patient-years and median survival time 4.1 years. The underlying cause of death was recorded as diabetes mellitus in 57.9% of those who died and none to disease of arteries, arterioles and capillaries. After adjustment for age and sex, smoking, SBP as a continuous variable, SBP >or=140 mm Hg and BMI <18.5 kg/m(2) (underweight) were predictors for mortality with respective odds ratios (95% confidence intervals) of 1.580 (1.030-2.425), 1.011 (1.000-1.022), 1.363 (1.007-1.845) and 1.889 (1.203-2.968); but hypertension, DBP as a continuous variable and DBP >or=90 mm Hg, BMI as a continuous variable and LEA level were not.

CONCLUSIONS

Mortality after LEA in Taiwanese diabetic patients is high. The most common cause of death was recorded as diabetes mellitus. After adjustment for age and sex, smoking, SBP and underweight are predictive for mortality; while LEA level is not.

Reduction in diabetic amputations over 11 years in a defined U.K. population: benefits of multidisciplinary team work and continuous prospective audit

OBJECTIVE

To assess changes in diabetic lower-extremity amputation rates in a defined relatively static population over an 11-year period following the introduction of a multidisciplinary foot team.

RESEARCH DESIGN AND METHODS

All diabetic patients with foot problems admitted to Ipswich Hospital, a large district general hospital, were identified by twice-weekly surveillance of all relevant in-patient areas and outcomes including amputations recorded.

RESULTS

The incidence of major amputations fell 62%, from 7.4 to 2.8 per 100,000 of the general population. Total amputation rates also decreased (40.3%) but to a lesser extent due to a small increase in minor amputations. Expressed as incidence per 10,000 people with diabetes, total amputations fell 70%, from 53.2 to 16.0, and major amputations fell 82%, from 36.4 to 6.7.

CONCLUSIONS

Significant reductions in total and major amputation rates occurred over the 11-year period following improvements in foot care services including multidisciplinary team work.

Scottish foot ulcer risk score predicts foot ulcer healing in a regional specialist foot clinic

OBJECTIVE

To determine whether patients developing ulcers had previously been identified as being at high risk of ulceration using the Scottish Care Information-Diabetes Collaboration (SCI-DC) ulcer risk score and whether the risk score predicts ulcer healing.

RESEARCH DESIGN AND METHODS

All patients attending the diabetes foot clinic with an ulcer had been assessed for foot ulcer risk using the SCI-DC risk calculator, which categorizes patients into low, moderate, or high risk of ulceration. Information on foot pulses, neuropathy, foot deformity, previous ulcer, ulcer site, depth, and presence of sepsis was recorded and related to ulcer outcome. Patients were followed up until outcome was achieved (median 3 months [range 1-33]).

RESULTS

Of patients attending the clinic with a foot ulcer (mean [+/-SD] age 67.3 +/- 12.7 years, 68% male), 68% were previously recognized to be at high risk of foot ulceration, and 98% were high or moderate risk. Of 221 ulcers, the healing rate was 75% overall but was lower for high-risk patients compared with other patients (68 vs. 93%; P < 0.0001). Of the remainder, 3% became chronic ulcers, 12% required minor or major amputation, and 10% died with their ulcer. In multivariate analysis, absent pulses, neuropathy, increased age, and deep ulcers were associated with poor healing. The combination of neuropathy and ischemia was particularly associated with poor outcome of an ulcer (61% healing).

CONCLUSIONS

The Scottish foot ulcer risk score predicts both ulcer development and ulcer healing. The risk score can be a useful initial guide to determine the likelihood of poor healing. The individual criteria contributing to this overall risk are similar to other studies.