Predictors of wound complications following major amputation for critical limb ischemia

The incidence of surgical site infection following major lower limb amputation: A systematic review

Surgical site infections (SSIs) following major lower limb amputation (MLLA) in vascular patients are a major source of morbidity. The objective of this systematic review was to determine the incidence of SSI following MLLA in vascular patients. This review was prospectively registered with the International Prospective Register of Systematic Reviews (CRD42023460645). Databases were searched without date restriction using a pre-defined search strategy. The search identified 1427 articles. Four RCTs and 21 observational studies, reporting on 50 370 MLLAs, were included. Overall SSI incidence per MLLA incision was 7.2% (3628/50370). The incidence of SSI in patients undergoing through-knee amputation (12.9%) and below-knee amputation (7.5%) was higher than the incidence of SSI in patients undergoing above-knee amputation, (3.9%), p < 0.001. The incidence of SSI in studies focusing on patients with peripheral arterial disease (PAD), diabetes or including patients with both was 8.9%, 6.8% and 7.2%, respectively. SSI is a common complication following MLLA in vascular patients. There is a higher incidence of SSI associated with more distal amputation levels. The reported SSI incidence is similar between patients with underlying PAD and diabetes. Further studies are needed to understand the exact incidence of SSI in vascular patients and the factors which influence this.

Clinical Effects of Tourniquet Use for Nontraumatic Major Lower Limb Amputation: A Two-Center Retrospective Cohort Study

BACKGROUND

To investigate the effect of tourniquet use on outcomes after major lower limb amputation (MLLA) due to peripheral arterial disease or complications from diabetes mellitus.

METHODS

In this 2-center retrospective observational study, vascular patients who underwent MLLA between January 1, 2016 and December 31, 2020 at 2 UK hospitals were identified using operating theater databases. Hospital databases were used to access medical records, operation notes, and laboratory reports. The use of a tourniquet in each MLLA was noted. The primary outcome was postoperative hemoglobin (Hb) drop (g/L). Secondary outcomes were units of allogeneic blood transfused perioperatively, 90-day revision rates, 90-day wound breakdown rates, surgical site infection (SSI) rates (at 30 days), and 90-day mortality. A follow-up index (a measure of follow-up completeness) was calculated for all 30-day and 90-day outcomes.

RESULTS

Four hundred seventy two patients underwent MLLA, of which 124 had a tourniquet applied. The median postoperative Hb drop was significantly lower in the tourniquet group compared to the nontourniquet group (13 [interquartile range 5-22] g/L vs. 20 [interquartile range 11-28] g/L; P ≤ 0.001). Thirty three point one percent (41) of tourniquet patients received a blood transfusion perioperatively, compared to 35.6% (124) of nontourniquet patients (P = 0.82). Sixteen percent (76) of patients required surgical revision within 90 days, with no significant difference between the tourniquet and nontourniquet group (20.2% tourniquet vs. 14.7% no tourniquet; P = 0.15). SSI rates (12.0% tourniquet vs. 10.6% no tourniquet, P = 0.66) and 90-day mortality (6.5% tourniquet vs. 10.1% no tourniquet; P = 0.23) were similar. Multivariable regression demonstrated that tourniquet use was independently associated with a reduced hemoglobin drop (β = -4.671, 95% confidence interval -7.51 to -1.83, P ≤ 0.001) but was not associated with wound breakdown, revision surgery, or SSI. Hypertension, SSI, and below-knee amputation using the skew flap technique were all significant predictors of revision surgery. All follow-up indices were ≥ 0.97.

CONCLUSIONS

Tourniquet use in MLLA was associated with a significantly lower fall in postoperative Hb without evidence of harm in terms of SSI, wound breakdown/revision rates, or mortality.

Comparative evaluation of transcutaneous oxygen tension and ankle-brachial index as predictors of reoperation following below-knee amputation

OBJECTIVE

Decision-making regarding level of lower extremity amputation is sometimes challenging. Selecting an appropriate anatomic level for major amputation requires consideration of tradeoffs between postoperative function and risk of wound complications that may require additional operations, including debridement and/or conversion to above-knee amputation (AKA). We evaluated the utility of common, non-invasive diagnostic tests used in clinical practice to predict the need for reoperations among patients undergoing primary, elective, below knee-amputations (BKAs) by vascular surgeons.

METHODS

Patients undergoing elective BKA over a 5-year period were identified using Current Procedural Terminology codes. Medical records were reviewed to characterize demographics, pre-amputation testing transcutaneous oxygen tension (TcPO2), and ankle-brachial index (ABI). The need for ipsilateral post-BKA reoperation (including BKA revision and/or conversion to AKA) regardless of indication was the primary outcome. Associations were evaluated using univariable and multivariable logistic regression models. Cutpoints for TcPO2 values associated with amputation reoperation were evaluated using receiver operating characteristic curves.

RESULTS

We identified 175 BKAs, of which 46 (26.3%) required ipsilateral reoperation (18.9% BKA revisions and 14.3% conversions to AKA). The mean age was 63.3 ± 14.8 years. Most patients were male (65.1%) and White (72.0%). Mean pre-amputation calf TcPO2 was 40.0 ± 20.5 mmHg, and mean ABI was 0.64 ± 0.45. In univariable models, post-BKA reoperation was associated with calf TcPO2 (odds ratio [OR], 0.97; 95% confidence interval [CI], 0.94-0.99; P = .013) but not ABI (OR, 0.53; 95% CI, 0.19-1.46; P = .217). Univariable associations with reoperation were also identified for age (OR, 0.97; 95% CI, 0.94-0.990; P = .003) and diabetes (OR, 0.43; 95% CI, 0.21-0.87; P = .019). No associations with amputation revision were identified for gender, race, end-stage renal disease, or preoperative antibiotics. Calf TcPO2 remained associated with post-BKA reoperation in a multivariable model (OR, 0.97; 95% CI, 0.94-0.99; P = .022) adjusted for age (OR, 0.98; 95% CI, 0.94-1.01; P = .222) and diabetes (OR, 0.98; 95% CI, 0.94-1.01; P = .559). Receiver operating characteristic analysis suggested a TcPO2 ≥38 mmHg as an appropriate cut-point for assessing risk for BKA revision (area under the curve = 0.682; negative predictive value, 0.91).

CONCLUSIONS

Reoperation after BKA is common, and reoperation risk was associated with pre-amputation TcPO2. For patients undergoing elective BKA, higher risk of reoperation should be discussed with patients with an ipsilateral TcPO2 <38 mmHg.

Postoperative Casting of Below-Knee Amputation Reduces StumpComplications

BACKGROUND

Against the technological advances in limb salvage, below-the-knee amputation (BKA) remains a common procedure. Although most elective BKA is classified as clean operation, the reported stump complication rate is much higher than predicted. Postoperative casting (PC) may reduce the number of these complications. The aim of this study was to compare the efficacy of elastic bandage with knee immobilizer (EBKI) and PC in BKA stump complications.

METHODS

Retrospective cohort comparison design identified patients who underwent BKA between 2000 and 2023 for non-correctable critical limb ischemia (CLI), or excessive tissue loss secondary to CLI, infection, severe neuropathy, or the combination of these and stratified them into 2 cohorts based on their postoperative stump dressing: EBKI and PC. BKAs that were done for trauma or neoplastic processes were excluded. The primary outcome measures: wound healing in 6 weeks and length of stay (LOS).

SECONDARY OUTCOME MEASURES

stump injury, infection, dehiscence, necrosis, number of higher-level amputations, knee contracture, and post-BKA mobility with Special Interest Group of Amputee Medicine score.

RESULTS

One hundred sixteen patients with 122 limbs (52 EBKI and 70 PC) were found who met inclusion criteria and analyzed. The groups were comparable in demographics and comorbidities and preoperative variables, including mobility. The primary wound healing at 6 weeks was higher (P = 0.007); wound dehiscence (P = 0.01) and LOS (P = 0.006) was lower in the PC group compared to EBKI group. The PC group achieved higher Special Interest Group of Amputee Medicine mobility score and lower number of contractures developed compared to the EBKI group.

CONCLUSIONS

Applying and maintaining PC to the BKA stump during the first month of healing reduced the incidence of stump complications, shortened the LOS, and improved postrehabilitation mobility results. We found no effect of PC on postoperative infections, stump necrosis, and higher-level amputations.

A scoping review of postoperative early rehabilitation programs after dysvascular-related amputations

BACKGROUND

After amputation, people face challenges including wound healing and decreased functional mobility. Early mobilization in acute hospital care has proved safe, improved function, and sped discharge. Still, loss of a leg complicates standing and early mobilization after amputation. Approaches to early mobilization and rehabilitation after amputation surgery have not been widely studied.

OBJECTIVES

To map the evidence regarding early postoperative mobilization after dysvascular amputation. Specific aims included identifying research designs and populations, describing rehabilitation approaches, and identifying gaps within the literature.

STUDY DESIGN

Scoping review following PRISMA-Sc guidelines.

METHODS

The a priori scoping review methodology conducted in June 2022 with English language and 20-year limits used the OVID Medline, OVID Allied and Complementary Medicine Database, Cumulative Index to Nursing and Allied Health Literature, Cochrane databases, and Journal of Prosthetics and Orthotics archive. Reviewer pairs used Covidence software to screen for inclusion (subjects with major lower limb dysvascular amputations, seen immediately postoperatively for hospital-based rehabilitation) with decisions by concurrence. Data for best practice scoping reviews were synthesized for analysis.

RESULTS

Two hundred ninety-six citations were screened, 13 full texts reviewed, and 8 articles included: 2 cohort studies, 3 case-control studies, 2 single-group interventional studies, and 1 case study. There were no randomized control trials or prospective comparison group trials.

CONCLUSIONS

Few studies were identified regarding acute rehabilitation after major lower extremity amputation. The limited evidence in this review suggested that early mobilization in the days after amputation was safe with or without use of temporary prostheses, although further research is certainly warranted.

A scoping review on nutritional intake and nutritional status in people with a major dysvascular lower limb amputation

PURPOSE

To systematically review literature on nutritional intake, nutritional status and nutritional interventions, and to study their association with short- and long-term clinical outcomes in people with a major dysvascular lower limb amputation.

METHODS

PubMed, Ovid, CINAHL, and The Cochrane Library were searched. Studies were included if nutritional intake, nutritional status, or nutritional interventions in people with a major dysvascular lower limb amputation were analyzed.

RESULTS

Of the 3038 unique papers identified, 30 studies were included. Methodological quality was moderate (1 study) or weak (29 studies). Limited information was available on nutritional intake (2 studies) and nutritional interventions (1 study). Nutritional intake and nutritional status were assessed by diverse methods. The percentage of people with a poor nutritional status ranged from 1% to 100%. In some studies, measures of poor nutritional status were associated with adverse short- and long-term clinical outcomes.

CONCLUSIONS

The percentage of people with a poor nutritional status is inconclusive in the major dysvascular lower limb amputation population, because of the heterogeneity of the assessment methods used. Some included studies reported a negative association between poor nutritional status and clinical outcomes. However, these results should be interpreted with caution, because of the limited quality of the studies available. Studies high in methodological quality and high in hierarchy of evidence are needed.IMPLICATIONS FOR REHABILITATIONThe proportion of people with a poor nutritional status in the major dysvascular lower limb amputation population is inconclusive.Poor nutritional status seems to affect clinical outcomes negatively.More uniformity in assessment of malnutrition in the major dysvascular lower limb amputation population is needed.

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.

Life Expectancy and Mortality After Lower Extremity Amputation: Overview and Analysis of Literature

Lower limb amputation (LLA) is a major surgical procedure with a significant impact on quality of life and mortality rates as well. Previous studies have shown that mortality rates following LLA can range from 9-17% within 30 days in the UK. This study systematically evaluates and reviews the published literature on life expectancy, mortality, and survival rates following lower extremity amputation (LEA). We have conducted a comprehensive search on Medline, CINAHL, and Cochrane Central databases resulting in 87 full-text articles. After a thorough review, only 45 (52.9%) articles met the minimum inclusion criteria for the study. Our analysis indicated 30-day mortality rates following LEA ranged from 7.1% to 51.4%, with an average mortality rate of 16.45% (SD 14.35) per study. Furthermore, 30-day mortality rates following below-knee amputation (BKA) and above-knee amputation (AKA) were found to be between 6.2% to 51.4%, X= 17.16% ± 19.46 SD and 12.7 to 21.7%, X= 16.15% ± 4.17 SD, respectively. Our review provides a comprehensive insight into the life expectancy, mortality, and survival rates following LEA. These findings highlight the importance of considering various factors, including patient age, presence of comorbidities such as diabetes, heart failure, and renal failure, and lifestyle factors such as smoking, in determining prognosis following LLA. Further research is necessary to determine strategies for improving outcomes and reducing mortality in this patient population.

Determinants of healing and readiness for prosthetic fitting after transtibial amputation: Integrative literature review

BACKGROUND

Healing after an amputation is a critical step in the recovery process. Delayed wound healing can lead to deconditioning and flexion contractures which reduce a patient's ability to use a prosthesis, ambulate independently, and return to community participation. The purpose of this integrative literature review was to determine the evidence-based physiological factors, comorbidities, postoperative management, and outcome measures associated with healing after transtibial amputation and address how these factors clinically guide readiness for prosthetic intervention.

METHODS

Authors completed Google Scholar searches to identify the most effective search terms to locate salient publications. Authors also completed literature searches of Ovid MEDLINE and Epub Ahead of Print, In-Process, and Other Nonindexed Citations and Daily <1946 to August 6, 2020>; Embase Classic + Embase <1947 to August 6, 2020>; and CINAHL Complete <1946 to August 6, 2020> databases using the following search terms: "transtibial," "trans-tibial," "below knee," "BKA," "amputation," amputation stump," "amputee," "wound healing," and "heal/s/ed/ing." The authors decided to include all levels of evidence to capture the maximum number of articles related to the determinants of healing and readiness for prosthetic fitting after transtibial amputation.

RESULTS

The searches identified 2067 potential articles for review, and after removing articles not relevant to the topic, authors completed full-text assessment on 20 articles. These included review and synthesis on three randomized controlled trials and 12 cohort studies.

CONCLUSION

Preamputation assessment is most critical in patients who present with a longer list of comorbidities and suboptimal physiologic factors known to predict wound complications. Clinical judgment is most subjective when determining the degree of healing over time. Readiness for prosthetic treatment need not wait for complete healing of the residuum. Future research is needed to assess transcutaneous oxygen profusion along with other noninvasive measures of blood flow and perfusion as a more objective way to track progression of healing over time. This objective methodology would quantify healing, reduce subjectivity, and promote research to compare different enhanced recovery after surgery protocols for their impact on healing after amputation.

Short-term risk prediction after major lower limb amputation: PERCEIVE study

BACKGROUND

The accuracy with which healthcare professionals (HCPs) and risk prediction tools predict outcomes after major lower limb amputation (MLLA) is uncertain. The aim of this study was to evaluate the accuracy of predicting short-term (30 days after MLLA) mortality, morbidity, and revisional surgery.

METHODS

The PERCEIVE (PrEdiction of Risk and Communication of outcomE following major lower limb amputation: a collaboratIVE) study was launched on 1 October 2020. It was an international multicentre study, including adults undergoing MLLA for complications of peripheral arterial disease and/or diabetes. Preoperative predictions of 30-day mortality, morbidity, and MLLA revision by surgeons and anaesthetists were recorded. Probabilities from relevant risk prediction tools were calculated. Evaluation of accuracy included measures of discrimination, calibration, and overall performance.

RESULTS

Some 537 patients were included. HCPs had acceptable discrimination in predicting mortality (931 predictions; C-statistic 0.758) and MLLA revision (565 predictions; C-statistic 0.756), but were poor at predicting morbidity (980 predictions; C-statistic 0.616). They overpredicted the risk of all outcomes. All except three risk prediction tools had worse discrimination than HCPs for predicting mortality (C-statistics 0.789, 0.774, and 0.773); two of these significantly overestimated the risk compared with HCPs. SORT version 2 (the only tool incorporating HCP predictions) demonstrated better calibration and overall performance (Brier score 0.082) than HCPs. Tools predicting morbidity and MLLA revision had poor discrimination (C-statistics 0.520 and 0.679).

CONCLUSION

Clinicians predicted mortality and MLLA revision well, but predicted morbidity poorly. They overestimated the risk of mortality, morbidity, and MLLA revision. Most short-term risk prediction tools had poorer discrimination or calibration than HCPs. The best method of predicting mortality was a statistical tool that incorporated HCP estimation.

Short-term and long-term outcomes of free flap reconstruction versus amputation for diabetic foot reconstruction in patients with end-stage renal disease

BACKGROUND

In Taiwan, the prevalence of diabetes mellitus complicated by end-stage renal disease (ESRD) has been increasing and diabetes-related foot amputation is commonplace. In recent years, limb salvage has become top priority. The long-term outcomes of patients on hemodialysis undergoing diabetic foot reconstruction using free flaps remain unknown.

METHODS

Data from the National Health Insurance Research Database on hemodialysis patients with type 2 diabetes who received amputation or free flap reconstruction surgery for diabetic foot ulcer were analyzed from 2000 to 2013 using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. After 1:4 propensity score matching, 86 and 344 patients were assigned to the free flap reconstruction and amputation groups, respectively.

RESULTS

The 5-year survival rate was significantly higher in patients who received free flap compared to the amputated group (1-year survival rate = 80.0% vs. 67.6%, p = 0.030; 3-year survival rate = 49.7% vs. 35.5%, p = 0.024; 5-year rate=30.1% vs. 19.9%, p = 0.018; however, after 5 years, the overall long-term survival rate was similar in both groups (p = 0.064). Patients who had lower limb amputation after flap reconstruction were susceptible to mortality (adjusted HR = 1.39; p = 0.069). Peripheral arterial disease was a dependent risk factor (HR = 1.45; p = 0.037) for long-term survival, whereas old age (> 75 years; HR = 1.65; p = 0.004), cerebrovascular disease (adjusted HR = 1.36; p = 0.011), and sepsis (adjusted HR = 1.85; p = 0.035) served as independent risk factors. Hemodialysis patients with diabetic foot ulcer who had limb salvaged showed a higher 5-year survival rate as compared to the amputated group.

Updated Integrated Framework for Making Clinical Decisions Across the Lifespan and Health Conditions

The updated Integrated Framework for Clinical Decision Making responds to changes in evidence, policy, and practice since the publication of the first version in 2008. The original framework was proposed for persons with neurological health conditions, whereas the revised framework applies to persons with any health condition across the lifespan. In addition, the revised framework (1) updates patient-centered concepts with shared clinical decision-making; (2) frames the episode of care around the patient's goals for participation; (3) explicitly describes the role of movement science; (4) reconciles movement science and International Classification of Function language, illustrating the importance of each perspective to patient care; (5) provides a process for movement analysis of tasks; and (6) integrates the movement system into patient management. Two cases are used to illustrate the application of the framework: (1) a 45-year-old male bus driver with low back pain whose goals for the episode of care are to return to work and recreational basketball; and (2) a 65-year-old female librarian with a fall history whose goals for the episode of care are to return to work and reduce future falls. The framework is proposed as a tool for physical therapist education and to guide clinical practice for all health conditions across the lifespan.

Incidence and Predictors of Surgical Site Infection Complications in Diabetic Patients Undergoing Lower Limb Amputation

BACKGROUND

Surgical site infections (SSIs) following lower extremity amputations (LEAs) are a major cause of patient morbidity and mortality. The objectives of this study are to investigate the annual incidence of SSI and risk factors associated with SSI after LEA in diabetic patients.

METHODS

LEAs performed on diabetic patients between 2005 and 2017 were retrospectively analyzed from the American College of Surgeons National Surgical Quality Improvement Program database. Incidence rates were calculated and analyzed for temporal change. Multivariable logistic regression was conducted to identify the independent predictors of SSIs in LEA.

RESULTS

In 21,449 diabetic patients, the incidence of SSIs was 6.8% after LEA, with an overall decreasing annual trend (P = 0.013). Amputation location (below-knee in reference to above-knee) [OR (95% CI): 1.35 (1.20 - 1.53), P <0.001], smoking [OR (95% CI): 1.25 (1.11 - 1.41), P <0.001)], female sex [OR (95% CI): 1.16 (1.03 - 1.30)], preoperative sepsis [OR (95% CI): 1.24 (1.10 - 1.40), P <0.001], P = 0.013], emergency status [OR (95% CI): 1.38 (1.17 - 1.63), P <0.001], and obesity [OR (95% CI): 1.59 (1.12 - 2.27), P = 0.009] emerged as independent predictors of SSIs, while moderate/severe anemia emerged as a risk-adjusted protective factor [OR (95% CI): 0.75 (0.62 - 0.91), P = 0.003]. Sensitivity analysis found that moderate/severe anemia, not body mass index (BMI) class, remained a significant risk factor in the development of SSIs in below-the-knee amputations; in contrast, higher BMI, not preoperative hematocrit, was significantly associated with an increased risk for SSI in above-the-knee amputations.

CONCLUSIONS

The incidence of SSIs after LEA in diabetic patients is decreasing. Overall, below-knee amputation, smoking, emergency status, and preoperative sepsis appeared to be associated with SSIs. Obesity increased SSIs in above-the-knee amputations, while moderate/severe preoperative anemia appears to protect against below-the-knee SSIs. Surgeons should take predictors of SSI into consideration while optimizing care for their patients, and future studies should investigate the role of preoperative hematocrit correction and how it may influence outcomes positively or negatively.

Analysis of Early Lower Extremity Re-amputation

BACKGROUND

Data is scarce regarding the need for early re-amputation to a higher anatomic level. This study seeks to define outcomes and risk factors for re-amputation.

METHODS

Patients undergoing primary major lower extremity amputation were identified within the 2012-2016 ACS-NSQIP database. Demographics, outcomes, and peri-operative characteristics were compared, and multivariable logistic regression model was used to determine association with early re-amputation.

RESULTS

Over a four-year period, 8306 below knee amputations and 6367 above knee amputations were identified. Thirty-day re-amputation occurred in 262 patients (1.8%) and was associated with increased length of stay (12.9 vs. 7.3 days, p<0.001), higher rates of readmission (64.9% vs. 13.6%, p<0.001), and overall complications (69.5% vs. 39.3%, p<0.01). On multivariable analysis, advanced age (OR 1.02, CI 1.01-1.03), smoking (OR 1.75, CI 1.32-2.33), dialysis dependence (OR 1.67, CI 1.23-2.26), preoperative septic shock (OR 2.53, CI 1.29-4.97), and bleeding disorders (OR 1.72, CI 1.34-2.22) were associated with early re-amputation.

CONCLUSIONS

Thirty-day re-amputation rates are low, but are associated with significant morbidity, prolonged hospitalization, and frequent readmissions.

Razjede in njihovo celjenje pri pacientih po amputaciji

Uvod: Najpogostejši vzroki, ki vplivajo na celjenje razjed pri pacientih po amputaciji, so periferna arterijska bolezen, sladkorna bolezen in kronična venska insuficienca. Namen raziskave je bil prepoznati dejavnike, ki lahko vplivajo na celjenje razjede na amputacijskem krnu.Metode: Uporabljena je bila kvantitativna neeksperimentalna raziskovalna metodologija. Izvedena je bila retrospektivna raziskava s pregledom negovalne dokumentacije o spremljanju razjede. V raziskavo je bilo vključenih 134 pacientov po amputaciji spodnjega uda z razjedo, hospitaliziranih v letu 2017. Uporabljeni sta bili opisna statistika in logistična regresija.Rezultati: Razjedo, nastalo zaradi različnih vzrokov, je imelo 134 pacientov. Ženske imajo v primerjavi v moškimi več možnosti za prisotnost razjede ob odpustu (RO = 4,8, 95 % IZ: 1–22), prav tako pacienti, ki so imeli razjedo že ob sprejemu (RO = 7,7, 95 % IZ: 3–19,2), in tisti z več kot eno razjedo (RO = 4,7, 95 % IZ: 1–22,3). Pri pacientih, ki imajo razjedo na amputacijskem krnu, imajo večjo možnost, da se bo ta do konca rehabilitacije zacelila (RO = 0,2, 95 % IZ: 0,1–0,6 p = 0,004).Diskusija in zaključek: Ugotovitve nakazujejo, da je pri ženskah večja verjetnost, da razjeda ob odpustu ne bo zaceljena, kot pri pacientih, pri katerih je bila razjeda prisotna že ob sprejemu, in pri tistih, ki imajo več razjed. Treba bi bilo izvesti raziskavo, ki bi zajela večje število pacientov. Prav tako bi bilo treba natančneje določiti parametre spremljanja.

Popliteal artery patency is an indicator of ambulation and healing after below-knee amputation in vasculopaths

BACKGROUND

The posterior flap is a conventional technique for closing a below-knee amputation (BKA) that uses the gastrocnemius and soleus muscle and relies on the popliteal and posterior compartment arteries. If the prior mentioned arterial blood supply is compromised, this flap likely relies on collateral flow. The purpose of this study is to identify and differentiate any significant associations between preoperative popliteal and tibial arterial flow and BKA outcomes and patient-reported function.

METHODS

A retrospective review identified patients from a single tertiary wound care center who received BKAs and angiogram between 2010 and 2017 by a single surgeon. BKA complications, wound healing, and amputee ambulatory status at latest follow-up were all stratified for differences according to baseline tibial vessel run-off (VRO) status, popliteal artery patency, and popliteal angioplasty outcome. Chi-square, Fisher's exact, and Wilcoxon rank sum tests were used with significance defined as p ≤ 0.05.

RESULTS

BKAs were performed on 313 patients, of which, 167 underwent preoperative angiography. Thirty-two were excluded due to lack of adequate follow-up leaving a total of 135 patients in the studied population. Diabetes was present in 87%, and 36% had end-stage renal disease. By the study's conclusion, 92% of BKAs had fully healed, with median time-to-healing of 79 days (range 19-1314 days). 60% of patients were ambulatory at 9.5 months. Higher VRO was associated with higher healing rates and lower complications and time-to-healing. The conversion rate of BKA to above-knee amputation (AKA) was 4%. Preoperative popliteal patency was associated with higher postoperative ambulation rates when compared to patients without popliteal flow preoperatively (patent: 71/109, 65%; occluded: 10/26, 40%; p = 0.02) and independently increased the likelihood of postoperative ambulation.

CONCLUSIONS

The posterior flap design for BKA works even in the setting of popliteal occlusion. Complication rates are higher in patients with more compromised blood flow, which may ultimately lead to AKA. Given poor ambulation rates in patients who undergo AKA, the results of this study should encourage surgeons to consider a more functional BKA, even in instances when the popliteal artery is occluded.

A predictive score for 30-day survival for patients undergoing major lower limb amputation for peripheral arterial obstructive disease

To analyze outcomes following major lower extremity amputations (mLEAs) for peripheral arterial obstructive disease, gangrene, infected non-healing wound and to create a risk prediction scoring system for 30-day mortality. In this single-center, retrospective, observational cohort study. All patients treated with above-the-knee amputation (AKA) or below-the-knee amputation (BKA) between January 1st, 2010 and June 30th, 2018 were identified. The primary outcome of interest was early (≤ 30 days) mortality. Secondary outcomes were postoperative complications and freedom from amputation stump revision/failure. We identified 310 (77.7%) mLEAs performed on 286 patients. There were 188 (65.7%) men and 98 (34.3%) women with a median age of 79 years (IQR, 69–83 years). We performed 257 (82.9%) AKA and 53 (17.1%) BKA. There were 49 (15.8%) early deaths, which did not differ among the age quartiles of this cohort (15.4% vs. 14.3% vs. 15.4% vs. 19.5%, P = 0.826). Binary logistic regression analysis identified age > 80 years (OR 2.24, 95% CI 1.17–4.31; P = 0.015), chronic obstructive pulmonary disease (OR 2.12, 95% CI 1.11–4.06; P = 0.023), and hemodialysis (OR 2.52, 95% CI 1.15–5.52; P = 0.021) to be associated with early mortality. The final score (range 0–10) identified two subgroups with different mortality at 30 days: lower-risk (score < 4, 10.8%), and higher-risk (score ≥ 4: 28.7%; OR 3.2, 95% CI 1.63–6.32; P < 0.001). In our experience, mLEAs still have a 14% mortality rate over the years. Our lower-risk group (score < 4) is characterized by a lower rate of perioperative death and longer survival.

Geographical socioeconomic disadvantage is associated with adverse outcomes following major amputation in diabetic patients

OBJECTIVE

Socioeconomic disadvantage is a known predictor of adverse outcomes and amputation in patients with diabetes. However, its association with outcomes after major amputation has not been described. Here, we aimed to determine the association of geographic socioeconomic disadvantage with 30-day readmission and 1-year reamputation rates among patients with diabetes undergoing major amputation.

METHODS

Patients from the Maryland Health Services Cost Review Commission Database who underwent major lower extremity amputation with a concurrent diagnosis of diabetes mellitus between 2015 and 2017 were stratified by socioeconomic disadvantage as determined by the area deprivation index (ADI) (ADI1 [least deprived] to ADI4 [most deprived]). The primary outcomes were rates of 30-day readmission and 1-year reamputation, evaluated using multivariable logistic regression models and Kaplan-Meier survival analyses.

RESULTS

A total of 910 patients were evaluated (66.0% male, 49.2% Black), including 30.9% ADI1 (least deprived), 28.6% ADI2, 19.1% ADI3, and 21.2% ADI4 (most deprived). After adjusting for differences in baseline demographic and clinical factors, the odds of 30-day readmission was similar among ADI groups (P > .05 for all). Independent predictors of 30-day readmission included female sex (odds ratio [OR], 1.45), Medicare insurance (vs private insurance; OR, 1.76), and peripheral artery disease (OR, 1.49) (P < .05 for all). The odds of 1-year reamputation was significantly greater among ADI4 (vs ADI1; OR, 1.74), those with a readmission for stump complication or infection/sepsis (OR, 2.65), and those with CHF (OR, 1.53) or PAD (OR, 1.59) (P < .05 for all).

CONCLUSIONS

Geographic socioeconomic disadvantage is independently associated with 1-year reamputation, but not 30-day readmission, among Maryland patients undergoing a major amputation for diabetes. A directed approach at improving postoperative management of chronic disease progression in socioeconomically deprived patients may be beneficial to reducing long-term morbidity in this high-risk group.

Sinusoidal changes in transcutaneous oxygen pressure, suggesting Cheyne-Stokes respiration, are frequent and of poor prognosis among patients with suspected critical limb ischemia

BACKGROUND AND AIMS

Transcutaneous oxygen pressure (TcpO₂) is used in patients with suspected critical limb ischemia (CLI). Sinusoidal changes (SC~) in TcpO₂ are found in patients with Cheyne-Stokes respiration (CSR). We aimed to determine the characteristics of TcpO₂ changes at rest in patients with suspected CLI, define the objective criteria for SC ~ TcpO₂ patterns (SC+), and estimate the prevalence of SC+ in our population and its impact on the outcome.

METHODS

We retrospectively analyzed 300 chest TcpO₂ recordings performed in a 16-month period. We determined the presence/absence of SC ~ TcpO₂ by visual analysis. We determined the acceptable error in the regularity of peaks of the cross-correlation with ROC curve analysis, among patients with typical SC ~ TcpO₂ and non-sinusoidal patterns. Then, we defined SC + as a minimum of five peaks, a standard deviation of TcpO₂ >1.25 mmHg, an error in regularity of peaks of the cross-correlation < 10%, and a cycle length between 30 and 100 s. In patients included until October 2019, we compared the outcome as a function of SC + or SC- with Cox models.

RESULTS

Mathematical detection of SC + found that 43 patients (14.3%) fulfilled all four defined criteria at the chest level, but only 23 did so at the limb level. In the follow-up of 207 patients, the presence of Sc ~ TcpO₂ at the chest significantly increased the risk of mortality: hazard ratio: 2.69 [95%CI: 1.37-5.30]; p < 0.005.

CONCLUSIONS

SC ~ TcpO₂ is frequent, and is associated with a poor outcome in patients with suspected CLI.

Risks and Risk Factors for Ipsilateral Re-Amputation in the First Year Following First Major Unilateral Dysvascular Amputation

OBJECTIVE

To identify timing, incidence, and risk factors for ipsilateral re-amputation within 12 months of first dysvascular amputation and to determine specific subgroups of patients at each amputation level that are at increased risk.

METHODS

A retrospective cohort study evaluating 7187 patients with first unilateral transmetatarsal (TM), transtibial (TT), or transfemoral (TF) amputation secondary to diabetes and/or peripheral artery disease (PAD) were identified in the VA Surgical Quality Improvement Program database between 2004 and 2014. Re-amputation was defined as any subsequent ipsilateral soft tissue/bony revision or amputation to a higher level. Twenty-three potential pre-operative risk factors (and nine potential interactions) were identified. A backward stepwise Cox regression was used to identify risk factors. Incidence rates and hazard ratios (HR) with 95% confidence intervals (CI) were computed.

RESULTS

The median time to highest level of re-amputation in the first year was 33 (interquartile range, 13-73) days. Risk of requiring at least one re-amputation was 41% (TM), 25% (TT), and 9% (TF). Risk factors associated with requiring re-amputation included chronic obstructive pulmonary disease, elevated white blood cell count, abnormal ankle brachial index (ABI), history of revascularisation, and alcohol misuse. TM patients who had diabetes only (HR 1.9; 95% CI 1.4-2.5), diabetes with an abnormal ankle brachial index (ABI) score (HR 2.4; 95% CI 1.8-3.2), and kidney failure (HR 1.7; 95% CI 1.3-2.1) were at the greatest risk of re-amputation. TT amputees who were smokers were also at an increased risk (HR 1.4; 95% CI 1.2-1.6).

CONCLUSION

This research identified important risk factors for failure of primary healing and need for re-amputation at the TM and TT level. If considering a TM amputation, caution should be exercised in patients with diabetes, in particular those with an abnormal ABI and/or renal failure. At the TT level, caution should be exercised in those who smoke.

Presurgery exercise-based conditioning interventions (prehabilitation) in adults undergoing lower limb surgery for peripheral arterial disease

BACKGROUND

Lower limb peripheral arterial disease (PAD) is a type of cardiovascular disease where the blood vessels that carry the blood to the legs are hardened and narrowed. The most severe manifestation of PAD is critical limb ischaemia (CLI). This condition results in symptoms of intractable rest pain, non-healing wounds and ulceration, gangrene or both. PAD affects more than 200 million people worldwide and approximately 3% to 5% of people aged over 40 have PAD, rising to 18% in people over 70 years of age. Between 5% to 10% of symptomatic PAD patients will progress to CLI over a five-year period and the five year cumulative incidence rate for asymptomatic patients with PAD deteriorating to intermittent claudication is 7%, with 21% of these progressing to CLI. Treatment options include angioplasty, bypass or amputation of the limb, when life or limb is threatened. People with CLI have a high risk of mortality and morbidity. The mortality rates during a surgical admission are approximately 5%. Within one year of surgery, the mortality rate rises to 22%. Postoperative complications are as high as 30% and readmission rates vary between 7% to 18% in people with CLI. Despite recent advances in surgical technology, anaesthesia and perioperative care, a proportion of surgical patients have a suboptimal recovery. Presurgery conditioning (prehabilitation) is a multimodal conditioning intervention carried out prior to surgery using a combination of exercise, with or without nutritional or psychological interventions, or both. The use of prehabilitation is gaining momentum, particularly in elderly patients undergoing surgery and patients undergoing colorectal cancer surgery, as a means of optimising fitness to improve the prognosis for people undergoing the physiological stress of surgery. People with PAD are characterised by poor mobility and physical function and have a lower level of fitness as a result of disease progression. Therefore, prehabilitation may be an opportunity to improve their recovery following surgery. However, as multimodal prehabilitation requires considerable resources, it is important to assess whether it is superior to usual care. This review aimed to compare prehabilitation with usual care (defined as a preoperative assessment, including blood and urine tests). The key outcomes were postoperative complications, mortality and readmissions within 30 days of the surgical procedure, and one-year survival rates.

OBJECTIVES

To assess the effectiveness of prehabilitation (preoperative exercise, either alone or in combination with nutritional or psychological interventions, or both) on postoperative outcomes in adults with PAD undergoing open lower limb surgery.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL, World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials register to 25 September 2019.

SELECTION CRITERIA

We considered all published and unpublished randomised controlled trials (RCTs) comparing presurgery interventions and usual care. Primary outcomes were postoperative complications, mortality and readmission to hospital within 30 days of the surgical procedure.

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed all records identified by the searches conducted by the Cochrane Vascular Information Specialist. We planned to undertake data collection and analysis in accordance with recommendations described in the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

We found no RCTs that met the inclusion criteria for this review.

AUTHORS' CONCLUSIONS

We found no RCTs conducted to determine the effects of prehabilitation on mortality or other postoperative outcomes when compared to usual care for patients with PAD. As a consequence, we were unable to provide any evidence to guide the treatment of patients with PAD undergoing surgery. To perform a randomised controlled trial of presurgery conditioning would be challenging but trials are warranted to provide solid evidence on this topic.

Closed incision negative pressure wound therapy may decrease wound complications in major lower extremity amputations

OBJECTIVE

Wound complications after major lower extremity amputations (LEAs) are a cause of significant morbidity in vascular surgery patients. Recent publications have demonstrated the efficacy of the closed incision negative pressure dressing at preventing surgical site infections (SSIs); however, there are few data on its use in major LEAs. This study sought to assess if closed incision negative pressure wound therapy (NPWT) would decrease the risk of complications as compared with a standard dressing in patients with peripheral vascular disease undergoing major LEA.

METHODS

Fifty-four consecutive patient limbs with a history of peripheral arterial disease underwent below-knee or above-knee amputations. This was a retrospective review of a prospectively maintained database from January 2018 to December 2019, and it included 23 amputations in the NPWT group and 31 amputations in the standard dressing group. NPWT using the PREVENA system was applied intraoperatively at the discretion of the operating surgeon and removed 5 to 7 days postoperatively. The standard group received a nonadherent dressing with an overlying compression dressing. Amputation incisions were assessed and wound complications were recorded. Student's t-test and two-sample proportion z-test were used for statistical analysis. A P value of less than .05 was considered statistically significant.

RESULTS

For comorbidities, there was a higher incidence of tobacco use in the NPWT as compared with the standard group (44% vs 13%; P = .011), as well as trends toward increased prior amputations, anemia, hyperlipidemia, and chronic obstructive pulmonary disorder in the NPWT group. For risk factors, there were more dirty wounds in the NPWT as compared with the standard group (52% vs 26%; P = .046). For outcomes, there were fewer wound complications in the NPWT as compared with the standard group (13% vs 39%; P = .037). The types of wound-related complications in the NPWT group included one wound dehiscence with a deep SSI, one superficial SSI, and one incision line necrosis. In the standard group, there were four wound dehiscences with deep SSI, three superficial SSIs, four incision line necroses, and one stump hematoma. The rates of perioperative mortality and amputation revision did not differ significantly between the NPWT and the standard groups (3% vs 4% and 4.3% vs 10%, respectively).

CONCLUSIONS

Closed incision NPWT may decrease the incidence of wound complications in vascular patients undergoing major LEA. This held true even among a population that was potentially at higher risk. This therapy may be considered for use in lower extremity major amputations.

Risk factors for reamputations in patients amputated after revascularization for critical limb-threatening ischemia

OBJECTIVE

Despite vascular intervention, patients with critical limb-threatening ischemia (CLTI) have a high risk of amputation. Furthermore, this group has a high risk for stump complications and reamputation. The primary aim of this study was to identify risk factors predicting reamputation after a major lower limb amputation in patients revascularized because of CLTI. The secondary aim was to investigate mortality after major lower limb amputation.

METHODS

There were 288 patients who underwent a major ipsilateral amputation after revascularization because of CLTI in Stockholm, Sweden, during 2007 to 2013. The main outcome was ipsilateral reamputation.

RESULTS

Of 288 patients, 50 patients had a reamputation and 222 died during the 11-year follow-up. Patients with ischemic pain as an indication for primary amputation had nearly four times higher risk for a reamputation compared with those with a nonhealing ulcer (subdistribution hazard ratio, 3.55; confidence interval, 1.55-8.17). Higher age was associated with an increased risk for death in the multivariable analysis (hazard ratio, 1.03; confidence interval, 1.02-1.04).

CONCLUSIONS

Patients with ischemic pain as an indication for amputation have an elevated risk of reamputation. Ischemic pain may be indicative of a more extensive and proximal ischemia compared with patients with foot tissue loss. An extended evaluation of the preoperative circulation before amputation may facilitate the choice of amputation level and could lead to a reduction of reamputations.

Clinical Practice Guidelines for the Rehabilitation of Lower Limb Amputation: An Update from the Department of Veterans Affairs and Department of Defense

Between 2015 and 2017, the US Department of Veterans Affairs and the US Department of Defense developed a clinical practice guideline for rehabilitation of lower limb amputation to address key clinical questions. A multidisciplinary workgroup of US Department of Veterans Affairs and US Department of Defense amputation care subject matter experts was formed, and an extensive literature search was performed which identified 3685 citations published from January 2007 to July 2016. Articles were excluded based on established review criteria resulting in 74 studies being considered as evidence addressing one or more of the identified key issues. The identified literature was evaluated and graded using the National Academies of Science GRADE criteria. Recommendations were formulated after extensive review. Eighteen recommendations were confirmed with four having strong evidence and workgroup confidence in the recommendation. Key recommendations address patient and caregiver education, consideration for the use of rigid and semirigid dressings, consideration for the use of microprocessor knees, and managed lifetime care that includes annual transdisciplinary assessments. In conclusion, this clinical practice guideline used the best available evidence from the past 10 yrs to provide key management recommendations to enhance the quality and consistency of rehabilitation care for persons with lower limb amputation.

Duplex Ultrasound May Predict the Best Level of Lower Limb Amputation in Patients with Chronic Limb-Threatening Ischemia: A Retrospective Observational Cohort Study

BACKGROUND

Despite improved revascularization options, many patients with chronic limb-threatening ischemia (CLI) require lower limb amputation. Duplex ultrasound (DUS) is recommended as first-choice imaging technique in CLI. However, the prognostic utility of DUS for planning lower limb amputations has never been described before. This study aims to evaluate if DUS and findings from physical examination could be used to help predict the best level of lower limb amputation in patients with CLI.

METHODS

A retrospective cohort of 124 patients with CLI and a lower limb amputation was analyzed. Outcome measurements were reoperation, revision, and conversion rates, which were related to findings from physical examination and DUS examinations.

RESULTS

Thirty-nine reoperations were performed, of which 17 stump revisions and 22 conversions were from below- to above-knee amputation. There was a discrepancy in findings of physical examination and DUS of 25% and 64% of femoral and popliteal pulsations respectively. Conversion rates increased with a more proximal occlusion on DUS. All patients with a vascular occlusion in the aortoiliac trajectory or deep femoral artery required a higher amputation level.

CONCLUSIONS

Physical examination seems to be unreliable, and therefore should not be used to assess the optimal level of lower extremity amputation. Performing a primary above-knee amputation in patients with vascular occlusion in the aortoiliac trajectory or deep femoral artery could significantly reduce reoperation rates.

Use of home negative pressure wound therapy in peripheral artery disease and diabetic limb salvage

Use of negative pressure wound therapy (NPWT) in peripheral artery disease (PAD) and diabetic limb salvage (DLS) improves wound healing by providing moist wound conditions, reducing exudate, controlling wound-bed infection, and stimulating granulation. NPWT duration may take several weeks, and home-based NPWT allows patient to recover in the community while minimising risks of prolonged hospitalisation. The aim of this study is to review the use and outcomes of home NPWT in PAD and DLS. The methodology is the retrospective review of patients who were discharged with home NPWT after in-patient PAD revascularisation and DLS debridement or minor amputations. The results included a total of 118 patients who received home NPWT between January 2017 and December 2017. The mean age was 62.8 years with 66% male and 34% female patients. The study population comprised 25% smokers, 98% patients with diabetics, 35% with ischemic heart disease, and 21% with end-stage renal failure (ESRF). Of which, 56% of patients required revascularisation while 31% of patients underwent foot debridement, 48% underwent toe amputations, and 20% underwent forefoot amputations. All patients received in-patient NPWT for a week before being discharged on home NPWT for 4 weeks. Then, 62% received targeted antibiotics regime while 36% received empirical antibiotics on discharge; 60% of patients achieved wound healing on home NPWT, with 9% requiring split-thickness skin graft; 4% required further surgical debridement, 16% required further minor amputation while 20% required major amputation. 9% required further home NPWT extension, with a mean length of 7.1 ± 4.7 weeks' extension. Overall survival of 1 year was 89%. Risk factors that predict the failure of home NPWT includes subjects with a background of ESRF and wet gangrene on presentation. Home NPWT is a useful adjunct in the management of PAD and DLS foot wounds.

Intradialytic hypotension is an important risk factor for critical limb ischemia in patients on hemodialysis

BACKGROUND

Critical limb ischemia (CLI) and intradialytic hypotension (IDH) are common complications in patients on hemodialysis (HD). However, limited data are available on whether IDH is related to CLI in these patients. The aim of this retrospective study was to evaluate whether IDH is a risk factor for CLI in HD patients.

METHODS

We examined the frequency of IDH in 147 patients who received HD between January 1 and June 30, 2012. Blood pressure was measured during HD every 30 min and IDH was defined as a ≥ 20 mmHg fall in systolic blood pressure compared to 30 min before and a nadir intradialytic systolic blood pressure < 90 mmHg. The primary study outcome was newly developed CLI requiring revascularization treatment or CLI-related death. We assessed the association of IDH with outcome using a multivariable subdistribution hazard model with adjustment for male, age, smoking and history of cardiovascular disease.

RESULTS

The median follow-up period was 24.5 months. Fifty patients (34%) had episodes of IDH in the study entry period. During follow-up, 14 patients received endovascular treatment and CLI-related death occurred in 1 patient. Factors associated with incident CLI in univariate analysis were age, smoking, diabetes mellitus, peripheral arterial disease, history of cardiovascular disease, and IDH. IDH was significantly associated with the outcome with the subdistribution hazard ratio of 3.13 [95% confidence interval, 1.05-9.37].

CONCLUSIONS

IDH was an independent risk factor for incident CLI in patients on HD.

Perioperative Outcomes of Lower Extremity Revascularization for Rest Pain and Tissue Loss

BACKGROUND

Critical limb ischemia (CLI) is the clinical manifestation of severe peripheral artery disease presenting as rest pain (RP) and tissue loss (TL). Most studies compare CLI as a homogenous group with claudication with limited database studies specifically studying these differences. We hypothesize that CLI should be stratified into RP and TL because of significant differences in disease severity, comorbidities, and outcomes.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database from 2012 to 2016 was reviewed. All patients with a postoperative diagnosis of CLI undergoing femoral to popliteal bypass (FPB) with vein or graft were identified. Patients were stratified into cohorts based on International Classification of Disease (ICD)-9 or ICD-10 codes for RP or TL (gangrene or ulcer). Univariate and multivariate analyses were performed to examine 30-day mortality, morbidity, major amputation, and readmission adjusting for demographics, comorbidities, and procedural details.

RESULTS

There were 5,304 patients. Compared to RP, patients with TL were older (P < 0.0001) and more likely to be dependent (P < 0.0001). TL patients were also more likely to have diabetes (P < 0.0001), congestive heart failure (P < 0.0001), renal failure (P = 0.004), dialysis (P < 0.0001), history of wound infection (P < 0.0001), and sepsis (P < 0.0001). TL patients had higher American Society of Anesthesiologists class (P < 0.0001), were less likely to be transferred from home (P < 0.0001), and more likely to receive an FPB with vein (P = 0.03). Patients with TL had worse perioperative outcomes compared with RP in terms of pneumonia (P = 0.004), unplanned intubation (P = 0.009), cardiac arrest requiring cardiopulmonary resuscitation (P = 0.003), bleeding requiring transfusions (P < 0.0001), sepsis (P < 0.0001), septic shock (P = 0.02), and reoperation (P < 0.0001). TL was associated with significantly higher 30-day morbidity (P < 0.0001), 30-day mortality (P < 0.0001), major amputation (P = 0.0004), and readmission rates (P = 0.005). Patients with TL compared with those with RP also had longer hospital stays (P < 0.0001) and days between operation to discharge (P < 0.0001). TL was independently associated with increased 30-day morbidity (OR: 1.16 [1.00-1.35]) and major amputation (OR: 2.48 [1.29-4.76]) compared with RP.

CONCLUSIONS

Patients with RP and TL have drastic differences that impact perioperative mortality and readmissions. TL is an independent predictor of 30-day morbidity and major amputation. The stratification of CLI into RP and TL can provide insight into variations in outcomes and provide a means to quantify the risks associated with the 2 manifestations of the disease.

Error-augmentation gait training to improve gait symmetry in patients with non-traumatic lower limb amputation: A proof-of-concept study

BACKGROUND

Asymmetrical stepping patterns are chronic gait impairment for individuals with non-traumatic lower limb amputation. Persistent gait asymmetries contribute to poor gait efficiency, decreased physical function, and development of secondary orthopedic conditions.

OBJECTIVES

Evaluate the feasibility and preliminary responsiveness of a treadmill-based, error-augmentation gait training protocol to improve gait symmetry in patients with non-traumatic transtibial amputation.

STUDY DESIGN

Single group, pre- and post-test.

METHODS

The error-augmentation gait training protocol involved walking on a split-belt treadmill with asymmetrical belt speeds for five 3-min sets. Spatiotemporal gait characteristics during overground walking at self-selected and fast walking speeds were assessed prior to, immediately after, and 20 min following the error-augmentation gait training protocol. Outcomes included practicality, implementation feasibility, safety, participant acceptability, and change in gait asymmetry.

RESULTS

All four participants completed the error-augmentation gait training protocol as prescribed, without adverse events, and found the intervention to be acceptable. Step length and stance time asymmetry during overground walking changed immediately following the error-augmentation gait training protocol with inconsistent changes retained after a 20 min washout period.

CONCLUSIONS

A single session of error-augmentation gait training is a feasible and safe intervention to modify gait asymmetry in patients with non-traumatic transtibial amputation. Additional study with larger sample sizes and repeated error-augmentation gait training dosing are warranted.

CLINICAL RELEVANCE

Gait training using error-augmentation on a split-belt treadmill may modify step length and stance time asymmetry for patients with non-traumatic transtibial amputation, but additional research is needed regarding short- and long-term efficacy. Additional training sessions may be needed to sustain initial changes achieved from a single session.

Predicting reamputation risk in patients undergoing lower extremity amputation due to the complications of peripheral artery disease and/or diabetes

Background

Patients undergoing amputation of the lower extremity for the complications of peripheral artery disease and/or diabetes are at risk of treatment failure and the need for reamputation at a higher level. The aim of this study was to develop a patient-specific reamputation risk prediction model.

Methods

Patients with incident unilateral transmetatarsal, transtibial or transfemoral amputation between 2004 and 2014 secondary to diabetes and/or peripheral artery disease, and who survived 12 months after amputation, were identified using Veterans Health Administration databases. Procedure codes and natural language processing were used to define subsequent ipsilateral reamputation at the same or higher level. Stepdown logistic regression was used to develop the prediction model. It was then evaluated for calibration and discrimination by evaluating the goodness of fit, area under the receiver operating characteristic curve (AUC) and discrimination slope.

Results

Some 5260 patients were identified, of whom 1283 (24·4 per cent) underwent ipsilateral reamputation in the 12 months after initial amputation. Crude reamputation risks were 40·3, 25·9 and 9·7 per cent in the transmetatarsal, transtibial and transfemoral groups respectively. The final prediction model included 11 predictors (amputation level, sex, smoking, alcohol, rest pain, use of outpatient anticoagulants, diabetes, chronic obstructive pulmonary disease, white blood cell count, kidney failure and previous revascularization), along with four interaction terms. Evaluation of the prediction characteristics indicated good model calibration with goodness-of-fit testing, good discrimination (AUC 0·72) and a discrimination slope of 11·2 per cent.

Conclusion

A prediction model was developed to calculate individual risk of primary healing failure and the need for reamputation surgery at each amputation level. This model may assist clinical decision-making regarding amputation-level selection.

Predictors of early mortality and readmissions among dialysis patients undergoing lower extremity amputation

OBJECTIVE

Patients receiving dialysis are at increased risk for lower extremity amputations (LEAs) and postoperative morbidity. Limited studies have examined differences in 30-day outcomes of mortality and health care use after amputation or the preoperative factors that relate to worsened outcomes in dialysis patients. Our objective was to examine dialysis dependency and other preoperative factors associated with readmission or death after LEA.

METHODS

A retrospective cohort study was conducted of dialysis-dependent and nondialysis patients undergoing major LEA in the 2012 to 2013 American College of Surgeons National Surgical Quality Improvement Program. Primary outcomes included death and hospital readmission within 30 days of amputation.

RESULTS

Of 6468 patients, 1166 (18%) were dialysis dependent. The dialysis cohort had more blacks (39% vs 23%), diabetes (76% vs 58%), below-knee amputations (62% vs 55%), and in-hospital deaths (8% vs 3%; all P < .001). The 30-day postoperative death rates (15% vs 7%) and readmission rates (35% vs 20% per 30 person-days; both P < .001) were higher in dialysis patients. Among the live discharges, the rate of any readmission or death within 30 days from amputation was highest in those aged ≥50 years (40% per 30 person-days). Multivariable analyses in the dialysis cohort revealed increased age, above-knee amputation, decreased physical status, heart failure, high preoperative white blood cell count, and low platelet count to be associated with death (P < .05; C statistic, 0.75). The only preoperative factor associated with readmission in dialysis patients was race (P = .04; C statistic, 0.58).

CONCLUSIONS

Readmission or death after amputation is increased among dialysis patients. Predicting which dialysis patients are at highest risk for death is feasible, whereas predicting which will require readmission is less so. Risk factor identification may improve risk stratification, inform reimbursement policies, and allow targeted interventions to improve outcomes.

Amputation stump perfusion is predictive of post-operative necrotic eschar formation

Background

A large proportion of patients develop poor amputation stump healing. We hypothesize that Laser-Assisted Fluorescent Angiography (LAFA) can predict inadequate tissue perfusion and healing.

Methods

Over an 8-month period we reviewed all patients who underwent lower extremity amputation and LAFA. We evaluated intra-operative LAFA global and segmental stump perfusion, and post-operative modified Bates-Jensen (mBJS) wound healing scores.

Results

In 15 patients, amputation stumps with lower global perfusion demonstrated higher mBJS (P = 0.01). Lower suture-line perfusion also correlated with more eschar formation (P < 0.001). Diabetic patients had higher mBJS (P = 0.009), lower stump perfusion (P = 0.02), and increased eschar volume (P < 0.001).

Conclusion

LAFA is a useful adjunct for intra-operative stump perfusion assessment and can predict areas of poor stump healing and eschar formation. Diabetic patients seem to be at higher risk of stump eschar formation.

Risk Factors for In-hospital Mortality and Reamputation Following Lower Limb Amputation

Objective

Studies on the outcomes of lower limb amputation have been limited by the use of selected study populations and small sample sizes. Although reamputation is an important outcome following lower limb amputation, the risk factors for reamputation remain to be elucidated. The present study was performed to identify risk factors for in-hospital death and reamputation following lower limb amputation.

Methods

Using a national inpatient database in Japan, we identified 13,774 patients who underwent lower limb amputation. We examined the patients' backgrounds and employed a multivariable logistic regression analysis to identify factors associated with in-hospital death or reamputation.

Results

The average age of the 13,774 patients was 72.4 years, and 63.1% (n=8694) were male. The overall in-hospital mortality rate was 10.8% (1481/13,774). The reamputation rate was 10.1% (782/7779) for patients who initially underwent foot or transtibial amputation (18.2% [391/2148] for foot amputations and 6.9% [391/5631] for transtibial amputations). Multivariable logistic regression analysis revealed higher age, male sex, peripheral vascular disease, use of insulin, hemodialysis, and higher numbers of comorbidities as significant risk factors for reamputation or in-hospital death. Use of hemodialysis was the strongest risk factor (odds ratio, 2.10; 95% confidence interval, 1.87-2.35).

Conclusions

The in-hospital mortality and reamputation rates following lower limb amputation were considerably high, reflecting the severely ill conditions of patients with advanced chronic diseases. Risk factors for in-hospital death and reamputation following lower limb amputation were identified. These should aid surgeons in determining a patient's risk of a poor outcome and deciding on the level of amputation.

Disarticulation of the knee: Analysis of an extended database on survival, wound healing, and ambulation

OBJECTIVE

This study analyzed survival of the amputee patients, wound healing, and ambulation after knee disarticulation (KD).

METHODS

Between July 1989 and October 2015, 153 KDs in 138 patients were performed at Nij Smellinghe Hospital, Drachten. Data were retrieved from hospital medical records. Wound healing was analyzed using nonparametric tests. Ambulation was recorded according to the Special Interest Group Amputation Medicine Workgroup Amputation and Prosthetics mobility scale.

RESULTS

Survival at 1, 6, and 12 months was 86%, 65%, and 55%, respectively. Wounds healed in 91% of patients. Wounds healed primarily in 57% of residual limbs, and healing was delayed in 33%. A transfemoral amputation (TFA) was performed in 10%. Patients with sagittal flaps had significantly poorer primary wound healing and delayed wound healing more often than patients with a dorsal-myocutaneous (dorsomyocutaneous) flap (P < .027). In total, 62% of patients were provided with a prosthesis. Preoperatively, 71% of the patients had intention to ambulate with prosthesis, of which 91% received prosthesis. Of these, 35% walked without the help of others. KD amputee patients who underwent a reamputation at the transfemoral level were significantly less ambulant than amputee patients who did not (P < .021).

CONCLUSIONS

If feasible, the dorsomyocutaneous flap technique seems to be the treatment of choice in KD. Because the wound complication rate of the group with a dorsomyocutaneous flap and the percentage of amputee patients who received prosthesis after KD fell within the same range as TFA amputee patients, KD may be an appropriate alternative when surgeons consider a TFA.

Predictors of complication following lower extremity amputation in diabetic end-stage renal disease

AIM

Patients with diabetic end-stage renal disease (ESRD) are at increased risk of lower extremity amputation (LEA) and postoperative complications compared to those without diabetic ESRD. This study sought to determine the factors that influence complications following LEA in patients with diabetic ESRD.

METHODS

A total of 41 patients with diabetic ESRD (total of 46 amputations) who underwent LEA were enrolled in this study. The electronic medical records were retrospectively reviewed to identify the predictors of postoperative complications. The outcomes were divided into three categories: no complications, minor complications (wounds requiring only local care or oral antibiotics), and major complications (requiring surgical intervention, further amputations, or inducing life-threatening morbidities and mortalities).

RESULTS

Multivariate logistic regression analysis demonstrated that underlying sepsis (P = 0.007) was the only significant risk factor for major complications, with an odds ratio demonstrating an 8.16 times increased risk of requiring another surgery or mortality compared to those without sepsis.

CONCLUSION

Preoperative sepsis is an independent risk factor for major complications after LEA in patients with diabetic ESRD. We advise particular caution when performing LEA in diabetic ESRD patients who are also septic. Early amputation, prior to the development of sepsis, is preferable.

A Series of 210 Peripheral Arterial Disease Below-Knee Amputations and Predictors for Subsequent Above-Knee Amputations

Objective: To review patient characteristics and outcomes after peripheral arterial disease (PAD)-related below-knee amputation (BKA), and identify risk factors predicting subsequent above-knee amputation (AKA).

Materials and Methods: A retrospective study of 210 BKAs between May 2008 and December 2015.

Results: The mean age of the study population was 66 years. Most of the patients had cardiovascular comorbidities, and 33% had end-stage renal failure (ESRF); 89% were American Society of Anesthesiologists 3 or 4. Previous ipsilateral lower-limb minor amputation was present in 49% and previous contralateral lower-limb major amputation was present in 20% patients. Limb salvage revascularization via angioplasty prior to BKA was performed in 73%, while 27% had extensive tissue loss that was not suitable for limb salvage. Postoperatively, 20% had BKA wound infection, with 3% requiring further surgical debridement, and 9% (19 patients) required subsequent AKA within 1 month. Overall survival analysis at 1–5 years was 75%, 66%, 64%, 59%, and 58%, respectively. Multivariate analysis showed ESRF (Odds Ratio [OR]=3.85; p=0.01) and preoperative non-ambulatory status (OR=5.58; p=0.01) to be independent risk factors in predicting for subsequent AKA.

Conclusion: Patients with underlying ESRF or preoperative non-ambulatory status may benefit from direct AKA if major amputation is required.

The emerging role of microdialysis in diabetic patients undergoing amputation for limb ischemia

Lower limb ischemia in diabetic patients is a result of macro- and microcirculation dysfunction. Diabetic patients undergoing limb amputation carry high mortality and morbidity rates, and decision making concerning the level of amputation is critical. Aim of this study is to evaluate a novel microdialysis technique to monitor tissue microcirculation preoperatively and predict the success of limb amputation in such patients. Overall, 165 patients with type 2 diabetes mellitus undergoing lower limb amputation were enrolled. A microdialysis catheter was placed preoperatively at the level of the intended flap for the stump reconstruction, and the levels of glucose, glycerol, lactate and pyruvate were measured for 24 consecutive hours. Patients were then amputated and monitored for 30 days regarding the outcome of amputation. Failure of amputation was defined as delayed healing or stump ischemia. Patients were divided into two groups based on the success of amputation. There was no difference between the two groups regarding gender, ASA score, body mass index, comorbidities, diagnostic modality used, level of amputation, as well as glucose, glycerol, and pyruvate levels. However, local concentrations of lactate were significantly different between the two groups and lactate/pyruvate (L/P) ratio was independently associated with failed amputation (threshold defined at 25.35). Elevated preoperative tissue L/P ratio is independently associated with worse outcomes in diabetic patients undergoing limb amputation. Therefore, preoperative tissue L/P ratio could be used as a predicting tool for limb amputation's outcome, although more clinical data are needed to provide safer conclusions.

A Canadian population-based description of the indications for lower-extremity amputations and outcomes

BACKGROUND

To our knowledge, there have been no previously published reports characterizing lower-extremity amputations in Canada. The objective of this study was to describe the indications and outcomes of lower-extremity amputations in the Canadian population.

METHODS

We performed a retrospective cohort study of all adult patients who underwent lower-extremity amputation in Canada between 2006 and 2009. Patients were identified from the Canadian Institute for Health Information's Discharge Abstract Database, which includes all hospital admissions across Canada with the exception of the province of Quebec. Pediatric, trauma, and outpatients were excluded.

RESULTS

During the study period, 5342 patients underwent lower-extremity amputations in 207 Canadian hospitals. The mean age was 67 ± 13 years, and 68% were men. Amputations were most frequently indicated after admission for diabetic complications (81%), cardiovascular disease (6%), or cancer (3%). In total, 65% of patients were discharged to another inpatient or long-term care facility, and 26% were discharged home with or without extra support. Most patients were diabetic (96%) and most (65%) required a below-knee amputation. Predictors of prolonged (> 7 d) hospital stay included amputation performed by a general surgeon; cardiovascular risk factors, such as diabetes, hypertension, ischemic heart disease, congestive heart failure, or hyperlipidemia; and undergoing the amputation in the provinces of Newfoundland and Labrador, New Brunswick, or British Columbia.

CONCLUSION

There is variability in the delivery of lower-extremity amputations and postoperative hospital discharges among surgical specialists and regions across Canada. Future work is needed to investigate the reasons for this variability and to develop initiatives to shorten postoperative hospital stays.

Prognosis of critical limb ischemia: Major vs. minor amputation comparison

Healthcare providers treating wounds have difficulties assessing the prognosis of patients with critical limb ischemia who had been discharged after complete healing of major amputation wounds. The word "major" in "major amputation" gives the impression of "being more severe" than "minor amputation." Therefore, even if wounds are healed after major amputation, they imagine that prognosis after major amputation would be poorer than that after minor amputation. We investigated the prognosis of diabetic nephropathy patients 2 years after amputations. Those patients underwent dialysis as well as amputation following percutaneous transluminal angioplasty for their foot wounds. They were ambulatory prior to these surgeries. Among 56 cases of minor amputation, 45 were males and 11 were females, and mortality was 41.1%. The mortality of cases with and without a coronary intervention history was 53.1% and 25.0%, respectively (p = 0.034). Among 10 cases of major amputation, 9 were males and 1 was female, and mortality was 60%. The mortality of cases with and without a coronary intervention history was 75.0% and 0%, respectively. Although we predicted poor prognosis in cases with major amputation, there was no significant difference in mortality 2 years after amputations (p = 0.267). Thus far poor prognosis has been reported for major amputation. It might be due to inclusion of the following patients: patients with wounds proximal to ankle joints, patients with extensive gangrene spreading to the lower legs, patients with septicemia from wound infection and who died around the time of operation, and patients with malnutrition. The results of our present study showed that the outcomes at 2 years postoperatively were similar between patients with major amputations and those with minor amputations, if surgical wounds were able to heal. We should not estimate the prognosis by the level of amputation, rather we should consider the effect of coronary intervention history on prognosis.

Blood transfusion is associated with increased risk of perioperative complications and prolonged hospital duration of stay among patients undergoing amputation

OBJECTIVE

We evaluated the outcomes of patients undergoing major lower-extremity amputation who received packed red blood cell transfusion.

METHODS

Using the dataset of the National Surgical Quality Improvement Program (2005-2011), we examined 5,739 above-knee and 6,725 below-knee amputations. Patients were stratified by perioperative (preoperative, intraoperative, or postoperative) blood transfusion. Outcomes included perioperative mortality, myocardial infarction (MI), thromboembolism, and duration of stay (DOS) at the hospital. Adjusted comparisons of outcomes between transfused and not-transfused patients were performed by matching the 2 groups for age, smoking, diabetes, renal failure, coronary artery disease, classification of the American Society of Anesthesiologists, functional status, and procedure type. Multivariable logistic and gamma regression were used to examine associations between transfusion and outcomes.

RESULTS

Of the 12,464 amputations in the study cohort 2,133 (17%) required transfusion. The majority of the cases were performed for critical limb ischemia (8,205 amputations; 66%) and the overall 30-days mortality was 9%. In both crude and matched cohorts, although perioperative mortality and cardiac complication rates were similar, transfusion was associated with a greater incidence of pneumonia (crude: 6.1% vs 3%, P < .001; matched: 5.9% vs 3.7%, P < .001), thromboembolism (2.5% vs 1.6%, P = .003; 2.5% vs 1.4%, P = .002) and longer DOS (18 ± 19 vs 13.6 ± 14.3 days, P < .001; 17.8 ± 18.4 vs 14.2 ± 14.5 days, P < .001). Multivariable adjustment for confounding variables in the crude cohort demonstrated that transfusion was independently associated with a greater odds of perioperative pneumonia (odds ratio [OR]:1.6; 95% confidence interval [CI]:1.3-2; P < .001), thromboembolism (OR 1.3, 95% CI 1.0-1.9, P = .09) and longer DOS (mean ratio: 1.1; 95% CI 1.1-1.6; P = .006).

CONCLUSION

Among patients who had major lower-extremity amputation, perioperative transfusion independently predicted greater risks for perioperative pneumonia, thromboembolism, and prolonged hospital DOS.