Survival evaluation of the patients with diabetic major lower-extremity amputations

Tourniquet use for people with peripheral arterial disease undergoing major lower limb amputations

BACKGROUND

At least 7000 major lower limb amputations (MLLAs) are performed in the UK each year, 80% of which are due to peripheral arterial disease (PAD). Intraoperative blood loss can have a deleterious effect on patient outcomes, and its replacement with transfused blood is not without risk. Tourniquets can be used in lower limb surgical procedures to provide a bloodless surgical field, minimise intraoperative blood loss, and reduce perioperative blood transfusion requirements. Although their safety has been demonstrated in certain orthopaedic operations, their use among people with PAD undergoing MLLA remains controversial. Many clinicians are concerned about tourniquets potentially compromising perfusion of the stump and thereby impacting wound healing through direct tissue injury, damage to the arterial supply of the wound, or both.

OBJECTIVES

To assess the safety and effectiveness of tourniquet use in people undergoing MLLA for complications of PAD, specifically with regard to intraoperative blood loss, change in haemoglobin levels, transfusion rates, wound healing, need for revision surgery, and postoperative complications including mortality.

SEARCH METHODS

We searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers from inception to 17 May 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing tourniquet use to no tourniquet use among people with PAD undergoing MLLA.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Primary outcomes were intraoperative blood loss, fall in haemoglobin levels, and perioperative blood transfusion requirement. Secondary outcomes were primary wound-healing rates, stump revision rates, other postoperative complications defined as per Clavien-Dindo classification, and postoperative mortality at 30 days and at maximal follow-up. We used GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

One RCT met our inclusion criteria, which was a prospective randomised blinded controlled trial conducted in Sheffield, UK in 2006. In total 64 participants undergoing transtibial amputation for non-reconstructable PAD were randomised to either tourniquet or no tourniquet to assess for intraoperative blood loss, fall in haemoglobin, transfusion requirement, wound healing, stump breakdown and revision. Ten participants were excluded postrandomisation (five from the tourniquet group and five from the no tourniquet group). The reported median volume of intraoperative blood loss was significantly less in the tourniquet group (255 mL (interquartile range (IQR) 150 to 572.5 mL))) compared to the control group (550 mL (IQR 255 to 1050 mL)) (P = 0.014). There was a significantly lower median drop in haemoglobin concentration in the tourniquet group (1.0 g/dL (IQR 0.6 to 2.4 g/dL)) compared to the control group (1.8 g/dL (IRQ 0 to 1.2 g/dL)) (P = 0.035). There was a significantly lower perioperative blood transfusion requirement in the tourniquet group (8 participants, 32%) compared to the control group (14 participants, 48%) (P = 0.047). There were no clear differences in wound breakdown, stump revision, primary wound healing at six weeks, postoperative complications (myocardial infarction, cardiac arrhythmias, pulmonary oedema), and death between groups. We assessed the one included study as at low risk of bias for sequence generation and blinding of outcome assessors; high risk of bias for incomplete outcome data and selective outcome reporting; and unclear risk of bias for allocation concealment, blinding of participants and personnel, and other sources of bias. We assessed the certainty of the evidence as low or very low due to risk of bias, small sample size, and the study being insufficiently powered for most outcomes.

AUTHORS' CONCLUSIONS

This review identified only one small historical RCT evaluating tourniquet use in MLLA. Tourniquets appeared to reduce intraoperative blood loss, drop in haemoglobin, and blood transfusion requirements following transtibial amputations for people with PAD. However, it is unclear whether tourniquets affect wound healing, stump revision rates, postoperative complications, or mortality. High-certainty evidence is required to inform clinical decision-making for the use of tourniquets in these patients.

Analysis of 5-year Mortality following Lower Extremity Amputation due to Vascular Disease

Mortality rates following major lower extremity amputations (LEAs) 30 days-365 days postoperative have decreased, but 5-year rates remain high at 40.4%-70%. These data may not reflect recent advances in peripheral arterial disease (PAD) care, and comorbidities of chronic PAD may lead to mortality more frequently than the amputation itself. Mortality rates between diabetic and nondiabetic patients were also analyzed.

Methods

The California Office of Statewide Health Planning and Development hospital database was queried for patients admitted January 1, 2007-December 31, 2018. ICD-9-CM codes identified patients with vascular disease and an amputation procedure.

Results

There were 26,669 patients. The 30-day, 90-day, 1-year, and 5-year major LEA mortality rates were 4.82%, 8.62%, 12.47%, and 18.11%, respectively. Weighted averages of 30-day, 90-day, 1-year, and 5-year major LEA mortality rates in the literature are 13%, 15.40%, 47.93%, and 60.60%, respectively. Mortality risk associated with vascular disease after amputation (hazard ratio = 22.07) was 11 times greater than risk associated with amputation-specific complications from impaired mobility (hazard ratio = 1.90; P < 0.01). Having diabetes was associated with lower mortality at 30 days, 90 days, and 1 year (P < 0.01) but not at 5 years (P = 0.22).

Conclusions

This study suggests that people may be living longer after their major LEA than was previously thought. This study suggests that patients' PAD may play a bigger role in contributing to their mortality than complications from loss of mobility postamputation. Although having diabetes was associated with lower postamputation mortality, the difference was no longer significant by 5 years.

Narrative Review of the Relationship Between CKD and Diabetic Foot Ulcer

Diabetic foot ulcer (DFU) and chronic kidney disease (CKD) are 2 significant complications of diabetes mellitus (DM). Up to 40% of patients with DM are expected to also develop CKD, and 19% to 34% will suffer from DFU during their lifetimes. However, data on the link between podiatric risk and the extent of CKD are scarce. Neuropathy, a key element of the International Working Group on the Diabetic Foot (IWGDF) classification, nevertheless appears to be related to the CKD stage. The incidence of DFU and its poor evolution also appear to be linked to the stage of CKD, with mortality reaching its peak in patients with end-stage renal disease (ESRD). Whatever, the decrease in the rate of diabetic foot amputation observed worldwide, especially for major amputations, is also observed in patients with ESRD. Specific actions taken for patients undergoing dialysis seems to improve the DFU prognosis. CKD and DFU share a number of elements of pathophysiology, the first of which is peripheral arterial disease (PAD). Uremic neuropathy and nutritional status also seem to create a link between the development of the 2 complications. This literature review provides an update on the complex and dynamic relationship between DFU and CKD. It examines the epidemiologic link between CKD and diabetic foot risk, CKD and DFU occurrence, and CKD and DFU prognosis. It focuses on the pathophysiological links between these 2 complications. Finally, it highlights the actions taken to improve management in the ESRD population that have reduced the rate of major amputations in this population by more than half.

Long-term Mortality After Nontraumatic Major Lower Extremity Amputation: A Systematic Review and Meta-analysis

Chronic wounds that lead to major lower extremity amputation have immense consequences on quality of life, and ultimately, mortality. However, mortality rates after lower extremity amputation for a chronic wound are broad within the literature and have escaped precise definition. This systematic review aims to quantify long-term mortality rates after major lower extremity amputation in the chronic wound population available in the existing literature. Ovid MEDLINE was searched for publications which provided mortality data after major, nontraumatic, primary lower extremity amputations. Lower extremity amputations were defined as below and above the knee amputation. Data from included studies was analyzed to obtain pooled 1-, 2-, 3-, 5- and 10-year mortality rates. Sixty-one studies satisfied inclusion criteria representing 36,037 patients who underwent nontraumatic major lower extremity amputation. Pooled mortality rates were 33.7%, 51.5%, 53%, 64.4%, and 80% at 1-, 2-, 3-, 5- and 10-year follow-up, respectively. Within the 8184 diabetic patients (types 1 and 2), 1- and 5-year mortality was 27.3% and 63.2%. Sources of mortality data were varied and included electronic medical records, national health and insurance registries, and government databases. Mortality after nontraumatic major lower extremity amputation is high, both in patients with diabetes as well as those without. Methods used to measure and report mortality are inconsistent, lack reliability, and may underestimate true mortality rates. These findings illustrate the need for a paradigm shift in wound management and improved outcomes reporting. A focus on amputation prevention and care within a multidisciplinary team is critical for recalcitrant ulcers.

Is Reconstruction of Unstable Midfoot Charcot Neuroarthropathy Cost Effective from a US Payer's Perspective?

BACKGROUND

Charcot neuroarthropathy is a morbid and expensive complication of diabetes that can lead to lower extremity amputation. Current treatment of unstable midfoot deformity includes lifetime limb bracing, primary transtibial amputation, or surgical reconstruction of the deformity. In the absence of a widely adopted treatment algorithm, the decision to pursue more costly attempts at reconstruction in the United States continues to be driven by surgeon preference.

QUESTIONS/PURPOSES

To examine the cost effectiveness (defined by lifetime costs, quality-adjusted life-years [QALYs] and incremental cost-effectiveness ratio [ICER]) of surgical reconstruction and its alternatives (primary transtibial amputation and lifetime bracing) for adults with diabetes and unstable midfoot Charcot neuroarthropathy using previously published cost data.

METHODS

A Markov model was used to compare Charcot reconstruction and its alternatives in three progressively worsening clinical scenarios: no foot ulcer, uncomplicated (or uninfected) ulcer, and infected ulcer. Our base case scenario was a 50-year-old adult with diabetes and unstable midfoot deformity. Patients were placed into health states based on their disease stage. Transitions between health states occurred annually using probabilities estimated from the evidence obtained after systematic review. The time horizon was 50 cycles. Data regarding costs were obtained from a systematic review. Costs were converted to 2019 USD using the Consumer Price Index. The primary outcomes included the long-term costs and QALYs, which were combined to form ICERs. Willingness-to-pay was set at USD 100,000/QALY. Multiple sensitivity analyses and probabilistic analyses were performed to measure model uncertainty.

RESULTS

The most effective strategy for patients without foot ulcers was Charcot reconstruction, which resulted in an additional 1.63 QALYs gained and an ICER of USD 14,340 per QALY gained compared with lifetime bracing. Reconstruction was also the most effective strategy for patients with uninfected foot ulcers, resulting in an additional 1.04 QALYs gained, and an ICER of USD 26,220 per QALY gained compared with bracing. On the other hand, bracing was cost effective in all scenarios and was the only cost-effective strategy for patents with infected foot ulcers; it resulted in 6.32 QALYs gained and an ICER of USD 15,010 per QALY gained compared with transtibial amputation. As unstable midfoot Charcot neuroarthropathy progressed to deep infection, reconstruction lost its value (ICER USD 193,240 per QALY gained) compared with bracing. This was driven by the increasing costs associated with staged surgeries, combined with a higher frequency of complications and shorter patient life expectancies in the infected ulcer cohort. The findings in the no ulcer and uncomplicated ulcer cohorts were both unchanged after multiple sensitivity analyses; however, threshold effects were identified in the infected ulcer cohort during the sensitivity analysis. When the cost of surgery dropped below USD 40,000 or the frequency of postoperative complications dropped below 50%, surgical reconstruction became cost effective.

CONCLUSIONS

Surgeons aiming to offer both clinically effective and cost-effective care would do well to discuss surgical reconstruction early with patients who have unstable midfoot Charcot neuroarthropathy, and they should favor lifetime bracing only after deep infection develops. Future clinical studies should focus on methods of minimizing surgical complications and/or reducing operative costs in patients with infected foot ulcers.

LEVEL OF EVIDENCE

Level II, economic and decision analysis.

Survival at 10 years following lower extremity amputations in patients with diabetic foot disease

BACKGROUND

Amputations are associated with markedly reduced long-term survival in patients with diabetic foot disease. However, there is paucity of long-term survival data in published literature.

METHODS

We searched the electronic case records and laboratory details of patients who underwent amputations between 1997 and 2006 to obtain at least 10 years of follow up data after the surgery to assess the survival rates and possible risk factors reducing survival in the year 2016. Amputation level below ankle was considered as minor and above ankle as major amputations.

RESULTS

Of the 233 cases (159 males; median age 68 years), 161 had major amputations. Of the 72 cases who had minor amputations initially, 63 needed a further amputation or contralateral amputation on follow up. One hundred seventy-seven patients (76%) were not alive after 10 years of follow up. The survival rates at 1, 3, 5, 7, and ≥10 years were 64%, 50%, 40%, 34%, and 24%, respectively. Maximum number of deaths occurred within 4 months of amputations. There was no difference between survival rates following major or minor amputations and among males or females. The only statistically significant parameter affecting lower survival rate was age ≥70 years, with each additional year of age increasing the hazard by a factor of 1.039 (95% CI: 1.024-1.054) or 3.9% (2.4-5.4%).

CONCLUSIONS

Five-year and 10-year survival rates were 40% and 24%, respectively, following diabetic foot amputations. Higher age ≥70 years was associated with lower survival rate compared with younger age groups after lower extremity amputations.

Low Back Pain in Adults With Transfemoral Amputation: A Retrospective Population-Based Study

BACKGROUND

Low back pain (LBP) is common among individuals with transfemoral amputation (TFA) and has a negative impact on quality of life. Little is known about health care utilization for LBP in this population and whether utilization varies by amputation etiology.

OBJECTIVE

To determine if individuals with TFA have an increased likelihood of seeking care or reporting symptoms of acute or chronic LBP during physician visits after amputation compared with matched individuals without amputation.

DESIGN

Retrospective cohort.

SETTING

Olmsted County, Minnesota (2010 population: 144 248).

PARTICIPANTS

All individuals with incident TFA (N = 96), knee disarticulation, and transfemoral amputation residing in Olmsted County between 1987 and 2014. Each was matched (1:10 ratio) with non-TFA adults on age, sex, and duration of residency. Individuals were divided by etiology of amputation: dysvascular and trauma/cancer.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASUREMENTS

Death and presentation for evaluation of LBP (LBP event) while residing in Olmsted County. LBP events were identified using validated International Classification of Diseases, Ninth Revision (ICD-9) codes and corresponding Berkson, Hospital International Classification of Diseases Adapted (HICDA), and ICD-10 diagnostic codes. Hurdle and competing-risk Cox proportional hazard models were used.

RESULTS

Having a TFA of either etiology did appear to correlate with increased frequency of LBP events, although this association was only statistically significant within the dysvascular TFA cohort (dysvascular TFA cohort: relative risk [RR] 1.80, 95% confidence interval [CI] 1.07-3.03, median follow-up 0.78 years; trauma/cancer TFA cohort: RR 1.14, 95% CI 0.58-2.22, median follow-up 7.95 years). In time to event analysis, dysvascular TFA had an increased risk of death and event. Obesity did not significantly correlate with increased frequency of LBP events or time to event for either cohort. At any given point in time, individuals with TFA of either etiology who had phantom limb pain were 90% more likely to have an LBP event (hazard ratio [HR] 1.91, 95% CI 1.11-3.31). Conditional on not dying and no LBP event within the first 2.5 years, individuals with prosthesis had a decreased risk of LBP events in subsequent years.

CONCLUSIONS

Risk of LBP events appears to vary by TFA etiology. Obesity did not correlate significantly with increased frequency of LBP event or time to event. Phantom limb pain correlated with decreased time to LBP event after amputation. The association between prosthesis receipt and LBP events is ambiguous.

LEVEL OF EVIDENCE

III.

Global Vascular Guidelines on the Management of Chronic Limb-Threatening Ischemia

GUIDELINE SUMMARY

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

Global vascular guidelines on the management of chronic limb-threatening ischemia

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

The risk of major cardiovascular events for adults with transfemoral amputation

BACKGROUND

It is well-known that the risk of cardiac disease is increased for those with lower-limb amputations, likely as a result of the etiology of the amputation. Using a longitudinal population-based dataset, we examined the association between transfemoral amputation (TFA) status and the risk of experiencing a major cardiac event for those undergoing either dysvascular or traumatic amputations. The association of receiving a prosthesis with the risk of experiencing a major cardiac event was also examined.

METHODS

Study Population: All individuals with TFA (N 162), i.e. knee disarticulation and transfemoral amputation, residing in Olmsted County, MN, between 1987 and 2014. Each was matched (1:10 ratio) with non-TFA adults on age, sex, and duration of residency.

DATA ANALYSIS

A competing risk Cox proportional hazard model was used to estimate the relative likelihood of an individual with a TFA experiencing a major cardiac event in a given time period as compared to the matched controls. The cohort was divided by amputation etiology: dysvascular vs trauma/cancer. Additional analysis was performed by combining all individuals with a TFA to look at the relationship between prosthesis receipt and major cardiac events.

RESULTS

Individuals with a dysvascular TFA had an approximately four-fold increased risk of a cardiac event after undergoing an amputation (HR 3.78, 95%CI: 3.07-4.49). These individuals also had an increased risk for non-cardiac mortality (HR 6.27, 95%CI: 6.11-6.58). The risk of a cardiac event was no higher for those with a trauma/cancer TFA relative to the able-bodied controls (HR 1.30, 95%CI: 0.30-5.85). Finally, there was no difference in risk of experiencing a cardiac event for those with or without prosthesis (HR 1.20, 95%CI: 0.55-2.62).

CONCLUSION

The high risk of initial mortality stemming from an amputation event may preclude many amputees from cardiovascular disease progression. Amputation etiology is also an important factor: cardiac events appear to be more likely among patients with a dysvascular TFA. Providing a prosthesis does not appear to be associated with a reduced risk of a major cardiac event following amputation.

Survival and associated risk factors in patients with diabetes and amputations caused by infectious foot gangrene

Background

Infectious gangrene of the foot is a serious complication of diabetes that usually leads to a certain level of lower-extremity amputation (LEA). Nevertheless, the long-term survival and factors associated with mortality in such patients have yet to be elucidated.

Methods

A total of 157 patients with type 2 diabetes who received treatment for infectious foot gangrene at a major diabetic foot center in Taiwan from 2002 to 2009 were enrolled, of whom 90 had major LEAs (above the ankle) and 67 had minor LEAs (below the ankle). Clinical data during treatment were used for the analysis of survival and LEA, and survival was tracked after treatment until December 2012.

Results

Of the 157 patients, 109 died, with a median survival time of 3.12 years and 5-year survival rate of 40%. Age [hazard ratio 1.04 (95% confidence interval 1.01–1.06)], and major LEA [1.80 (1.05–3.09)] were independent factors associated with mortality. Patients with minor LEAs had a better median survival than those with major LEAs (5.5 and 1.9 years, respectively, P < 0.01). An abnormal ankle-brachial index was an independent risk factor [odds ratio 3.12 (95% CI 1.18–8.24)] for a poor outcome (major LEA) after adjusting for age, smoking status, hypertension, major adverse cardiac events, and renal function.

Conclusions

Efforts to limit amputations below the ankle resulted in better survival of patients with infectious foot gangrene. An abnormal ankle-brachial index may guide physicians to make appropriate decisions with regards to the amputation level.