The impact of glycosylated hemoglobin and diabetes mellitus on wound-healing complications and infection after foot and ankle surgery

Impact of preoperative haemoglobin A1c levels on postoperative outcomes in adults undergoing major noncardiac surgery: A systematic review

AIMS

Diabetes is known to increase morbidity and mortality after major surgery. However, literature is conflicting on whether elevated preoperative haemoglobin A1c (HbA1c) levels are associated with worse outcomes following major noncardiac surgery. We aimed to investigate the effect of incremental preoperative HbA1c levels on postoperative outcomes in adults who had undergone major noncardiac surgery.

METHODS

We systematically searched PubMed, EMBASE and the Cochrane Library databases for eligible studies published between January 2012 and July 2023. Randomised controlled trials and observational studies (cohort and case-control studies) which measured HbA1c within 6 months before surgery and compared outcomes between at least three incremental subgroups or analysed HbA1c as a continuous variable were included. The systematic review protocol was registered with PROSPERO (CRD42023391946).

RESULTS

Twenty observational studies investigating outcomes across multiple surgical types were included. Higher preoperative HbA1c levels were associated with increased odds of overall postoperative complications, postoperative acute kidney injury, anastomotic leak, surgical site infections and increased length of stay. Each 1% increase in preoperative HbA1c was associated with increased odds of these complications. No association with reoperations and 30-day mortality was identified. The literature was highly variable with respect to composite major complications, perioperative cardiovascular events, hospital readmissions, postoperative pneumonia and systemic thromboembolism.

CONCLUSIONS

Current evidence suggested that higher preoperative HbA1c levels were associated with increased odds of postoperative complications and extended length of stay in adults undergoing major noncardiac surgery. Further high-quality studies would be needed to quantify the risks posed and determine whether early intervention improves outcomes.

Bone Fragility in Diabetes and its Management: A Narrative Review

Bone fragility is a serious yet under-recognised complication of diabetes mellitus (DM) that is associated with significant morbidity and mortality. Multiple complex pathophysiological mechanisms mediating bone fragility amongst DM patients have been proposed and identified. Fracture risk in both type 1 diabetes (T1D) and type 2 diabetes (T2D) continues to be understated and underestimated by conventional risk assessment tools, posing an additional challenge to the identification of at-risk patients who may benefit from earlier intervention or preventive strategies. Over the years, an increasing body of evidence has demonstrated the efficacy of osteo-pharmacological agents in managing skeletal fragility in DM. This review seeks to elaborate on the risk of bone fragility in DM, the underlying pathogenesis and skeletal alterations, the approach to fracture risk assessment in DM, management strategies and therapeutic options.

Diabetic Osteomyelitis: Oral versus Intravenous Antibiotics at a Single Level 1 Academic Medical Trauma Center

Residual osteomyelitis is a frequent problem following surgical intervention for diabetic foot infection. The Infectious Disease Society of America guidelines recommend a prolonged course of antibiotics for treatment of residual osteomyelitis. Recent literature suggests oral antibiotic therapy is not inferior to IV therapy. The primary aim of this study was to evaluate treatment success in 128 patients receiving oral versus IV antibiotics for residual osteomyelitis in the diabetic foot after amputation at a Level 1 academic medical trauma center. Treatment success was defined as completion of at least 4 weeks of antibiotic therapy, complete surgical wound healing, and no residual infection requiring further debridement or amputation within 1 year of the initial surgery. Patients with peripheral arterial disease were excluded. A retrospective chart review was performed, and we found no statistically significant difference in treatment success between these two groups (p = .2766). The median time to healing for oral antibiotic treatment was 3.17 months compared to 4.06 months for IV treatment (p = .1045). Furthermore, there was no significant difference in group demographics or comorbidities, aside from more patients in the IV group having coronary artery disease (p = .0416). The type of closure and whether the infection was single or polymicrobial were also not associated with a difference in outcomes between the two treatment arms. The results of the present study suggest oral antibiotics for treatment of residual osteomyelitis are not inferior to IV therapy and may be more efficacious for certain patients regarding cost and ease of administration.

A Prospective Evaluation for a Possible Safe Skin Bridge in Elective Foot Surgery

Background

In foot and ankle surgery, adequate surgical exposure often requires multiple incisions to be used near one another, thus creating a skin bridge. As the skin bridge becomes narrower, the wound edge vitality is potentially compromised and therefore the wound's ability to heal. The impact of local, host, and surgical factors on wound healing are well documented in the literature; however, little is known about the role of the skin bridge. The aim of this study is to determine if there is a recommendable safe skin bridge in elective foot and ankle surgery.

Methods

A prospective study was performed on 56 patients with 60 feet who had elective foot surgery. The length of each incision and distance between the incisions were recorded. The wounds were assessed for complications at 2, 4, and 6 weeks after surgery. Patient demographics and host risk factors were documented.

Results

The average incision length was 5.5 (range: 3-8.5) cm. The average skin bridge was 3.9 (range: 2-6.8) cm. Five (8.3%) of the 60 feet developed a wound complication. Four (80%) of these patients had a known comorbidity. Two patients had diabetes and 2 were smokers. The incidence of relevant comorbidities was 5.5% (n = 3) for patients without a wound complication (P < .001). Age did not differ significantly between patients with and without a wound complication. Patients with a wound complication had significantly longer incision lengths (P = .047). There was no significant independent association between skin bridge width and risk of wound complications (P > .05) with skin bridge widths of 2 cm or larger.

Conclusion

In this relatively small cohort of 60 elective operative foot surgeries, we did not find increased wound complications in skin bridges 2 cm or larger, when meticulous surgical technique is practiced and host risk factors are optimized.

Level of Evidence

Level III, prospective case control study.

Diabetes status and postoperative complications for patients receiving open rotator cuff repair

Background

Diabetic patients are known to have poor wound healing and worse outcomes following surgeries. The purpose of this study is to evaluate diabetes status and complications for patients receiving open rotator cuff repair.

Methods

Patients undergoing open rotator cuff repair from 2006 to 2018 were identified in a national database. Patients were stratified into 3 cohorts: no diabetes mellitus, non-insulin dependent diabetes mellitus (NIDDM), and insulin dependent diabetes mellitus (IDDM). Differences in demographics, comorbidities, and complications were assessed with the use of bivariate and multivariate analyses.

Results

Of 7678 total patients undergoing open rotator cuff repair, 6256 patients (81.5%) had no diabetes, 975 (12.7%) had NIDDM, and 447 (5.8%) had IDDM. Bivariate analyses revealed that IDDM patients had increased risk of mortality, extended length of stay, and readmission compared to non-diabetic patients (p < 0.05 for all). IDDM patients had higher risks of major complications and readmission relative to NIDDM patients (p < 0.05 for both). On multivariate analysis, there were no differences in any postoperative complications between the non-diabetic, NIDDM, and IDDM groups.

Discussion

Diabetes does not affect postoperative complications following open rotator cuff repairs. Physicians should be aware of this finding and counsel their patients appropriately.Level of Evidence: III.

The impact of youth-onset type 2 diabetes on postoperative wound healing complications

Youth-onset type 2 diabetes mellitus is associated with a more rapid decline in β cells, and earlier onset of medical complications compared to adult-onset diabetes. However, its impact on surgical wounds remains less clear. Therefore, this study aimed to determine whether youth-onset diabetes is a risk factor for wound healing complications in the 30-day postoperative period. To do so, the National Surgical Quality Improvement Program Database years 2012-2019 was analysed. Patients aged 18-24 with non-insulin-dependent diabetes were included. Outcomes assessed included wound infections, wound dehiscence, readmissions, and reoperation. Univariate analysis identified differences between the diabetic and non-diabetic cohorts after which, multivariate logistic regression was employed to control for potential confounding. Analysis included 1589 diabetic and 196,902 non-diabetic patients ages 18-24. The diabetic cohort exhibited a higher proportion of female (83.8% vs. 55.2%, p < 0.001), non-white (22.7% vs. 19.5%, p = 0.001), and Hispanic patients (16.2% vs. 13.6%, p = 0.002). Diabetic patients were less likely to have dirty or contaminated wounds (16.2% vs. 25.2%, p < 0.001); however had increased rates of superficial surgical site infections (SSSIs; 2.0% vs. 0.8%, p < 0.001) and readmission (4.0% vs. 3.0%, p = 0.026). After regression, diabetes remained a significant positive predictor of SSSI (odds ratio: 1.546, p = 0.022); however, it no longer significantly predicted 30-day readmission. Overall, this analysis of a large multicentre surgical outcomes database found that when compared to non-diabetics, youth-onset diabetic patients exhibited a higher proportion of SSSIs in the 30-day postoperative period. These infections were found, despite the diabetic cohort exhibiting lower rates of wound contamination. After controlling for confounding variables, youth-onset diabetes remained a significant predictor of SSSI. Clinically, prevention and treatment of diabetes along with judicious wound care is recommended.

Operative Ankle Fractures in Complicated Diabetes: Outcomes of Prolonged Non-Weightbearing

Diabetes increases the risk of developing postoperative complications such as superficial and deep infection, wound dehiscence, and revisional surgery. Prolonged non-weightbearing and/or augmented fixation may reduce postoperative complications in complicated diabetic ankle fractures. This study's purpose was to compare the development of postoperative infection, wound dehiscence, and revisional surgery in complicated diabetic ankle fractures with respect to weightbearing status. We hypothesized that fewer complications would occur in patients with prolonged non-weightbearing. Medical records of 90 surgically treated complicated diabetic ankle fractures were retrospectively reviewed for postoperative radiographs, weightbearing status, and complications. Complicated diabetes was defined as HbA1c ≥ 8% within 1 year of surgery. Twenty-four out of 90 patients had prolonged non-weightbearing status, which was defined as ≥ 8 weeks of non-weightbearing postoperatively. Twelve out of 90 patients had augmented fixation, which was defined as standard open reduction and internal fixation plus ≥ 2 tetra-cortical or > 2 tri-cortical syndesmotic screws with medial plate, external fixation, or other combination. Thirty-three out of 90 patients (36.7%) patients developed complications postoperatively. Patients with prolonged non-weightbearing had less complications (29.2% vs 39.4%, p = .37) and larger HbA1c values compared with early weightbearing patients (10.0 vs 9.3, p = .04). A one-unit increase in creatinine value (mg/dL) revealed a 3.15-fold increase in development of complications (95% confidence interval 1.29-7.65, p = .01). Although not statistically significant, complicated diabetic ankle fractures treated with prolonged non-weightbearing had less complications postoperatively except for ankle Charcot. Creatinine can be utilized as an independent risk factor for postoperative complications in this population.

Surgical Outcomes in Urogynecology-Assessment of Perioperative and Postoperative Complications Relative to Preoperative Hemoglobin A1c-A Fellow's Pelvic Research Network Study

OBJECTIVES

Poor control of diabetes mellitus is a known predictor of perioperative and postoperative complications. No literature to date has established a hemoglobin A1c (HbA1c) cutoff for risk stratification in the urogynecology population. We sought to identify an HbA1c threshold predictive of increased risk for perioperative and postoperative complications after pelvic reconstructive surgery.

METHODS

This multicenter retrospective cohort study involving 10 geographically diverse U.S. female pelvic medicine and reconstructive surgery programs identified women with diabetes who underwent prolapse and/or stress urinary incontinence surgery from September 1, 2013, to August 31, 2018. We collected information on demographics, preoperative HbA1c levels, surgery type, complications, and outcomes. Sensitivity analyses identified thresholds of complications stratified by HbA1c. Multivariate logistic regression further evaluated the association between HbA1c and complications after adjustments.

RESULTS

Eight hundred seven charts were identified. In this diabetic cohort, the rate of overall complications was 44.1%, and severe complications were 14.9%. Patients with an AM HbA1c value of 8% or greater (reference HbA1c, <8%) had an increased rate of both severe (27.1% vs 12.8%, P < 0.001) and overall complications (57.6% vs 41.8%, P = 0.002) that persisted after multivariate logistic regression (odds ratio, 2.618; 95% confidence interval, 1.560-4.393 and odds ratio, 1.931; 95% confidence interval, 1.264-2.949, respectively). Mesh complications occurred in 4.6% of sacrocolpopexies and 1.7% of slings. The average HbA1c in those with mesh exposures was 7.5%.

CONCLUSIONS

Preoperative HbA1c of 8% or higher was associated with a 2- to 3-fold increased risk of overall and severe complications in diabetic patients undergoing pelvic reconstructive surgery that persisted after adjustments.

Diabetes and Bone Fragility

Diabetes is a highly prevalent disease with complications that impact most bodily systems. However, the impact of diabetes on bone health is frequently ignored or underestimated. Both type 1 (T1D) and type 2 diabetes (T2D) are associated with a higher risk of fractures, albeit through different mechanisms. T1D is characterized by near total insulinopenia, which affects the anabolic tone of bone and results in reduced bone mineral density (BMD). Meanwhile, patients with T2D have normal or high BMD, but carry an increased risk of fractures due to alterations of bone microarchitecture and a local humoral environment that stimulates osteoclast activity. Chronic hyperglycemia induces non-enzymatic glycation of collagen in both types of diabetes. Epidemiological evidence confirms a largely increased fracture risk in T1D and T2D, but also that it can be substantially reduced by opportune monitoring of fracture risk and appropriate treatment of both diabetes itself and osteopenia or osteoporosis if they are present. In this review, we summarize the mechanistic, epidemiological, and clinical evidence that links diabetes and bone fragility, and describe the impact of available diabetes treatments on bone health.

Trends in Rates of Infections Requiring Hospitalization Among Adults With Versus Without Diabetes in the U.S., 2000-2015

OBJECTIVE

Vascular complications of diabetes have declined substantially over the past 20 years. However, the impact of modern medical treatments on infectious diseases in people with diabetes remains unknown.

RESEARCH DESIGN AND METHODS

We estimated rates of infections requiring hospitalizations in adults (≥18 years) with versus without diabetes, using the 2000-2015 National Inpatient Sample and the National Health Interview Surveys. Annual age-standardized and age-specific hospitalization rates in groups with and without diabetes were stratified by infection type. Trends were assessed using Joinpoint regression with the annual percentage change (Δ%/year) reported.

RESULTS

In 2015, hospitalization rates remained almost four times as high in adults with versus without diabetes (rate ratio 3.8 [95% CI 3.8-3.8]) and as much as 15.7 times as high, depending on infection type. Overall, between 2000 and 2015, rates of hospitalizations increased from 63.1 to 68.7 per 1,000 persons in adults with diabetes and from 15.5 to 16.3 in adults without diabetes. However, from 2008, rates declined 7.9% in adults without diabetes (from 17.7 to 16.3 per 1,000 persons; Δ%/year -1.5, P < 0.01), while no significant decline was noted in adults with diabetes. The lack of decline in adults with diabetes in the later period was driven by significant increases in rates of foot infections and cellulitis as well as by lack of decline for pneumonia and postoperative wound infections in young adults with diabetes.

CONCLUSIONS

Findings from this study highlight the need for greater infectious risk mitigation in adults with diabetes, especially young adults with diabetes.

What Is the Treatment "Algorithm" for Infection After Ankle or Hindfoot Arthrodesis?

RECOMMENDATION

There is no universal algorithm for addressing the infected ankle or subtalar arthrodesis. A potential algorithm created by consensus is.

LEVEL OF EVIDENCE

Consensus.

DELEGATE VOTE

Agree: 100%, Disagree: 0%, Abstain: 0% (Unanimous, Strongest Consensus).

Bone Reconstruction in the Diabetic Foot

Surgical bone reconstructive procedures of the foot and ankle in diabetic patients must be considered when performing evaluation of a diabetic foot for patients with preulcerative lesions and preexisting wounds. Preventive deformity correction can reduce the potential risk of ulceration, infection, and possible amputation in a patient with an at-risk foot type. It can also expedite wound healing and prevent further breakdown in a patient with lower extremity ulcerations. This article discusses different types of surgical bone reconstructive procedures as preventive and prophylactic deformity corrections to reduce osseous deformity, minimize preulcerative lesions, and increase limb-salvage rates in the compromised patient.

Emerging therapies for cartilage regeneration in currently excluded 'red knee' populations

The field of articular cartilage repair has made significant advances in recent decades; yet current therapies are generally not evaluated or tested, at the time of pivotal trial, in patients with a variety of common comorbidities. To that end, we systematically reviewed cartilage repair clinical trials to identify common exclusion criteria and reviewed the literature to identify emerging regenerative approaches that are poised to overcome these current exclusion criteria. The term “knee cartilage repair” was searched on clinicaltrials.gov. Of the 60 trials identified on initial search, 33 were further examined to extract exclusion criteria. Criteria excluded by more than half of the trials were identified in order to focus discussion on emerging regenerative strategies that might address these concerns. These criteria included age (<18 or >55 years old), small defects (<1 cm²), large defects (>8 cm²), multiple defect (>2 lesions), BMI >35, meniscectomy (>50%), bilateral knee pathology, ligamentous instability, arthritis, malalignment, prior repair, kissing lesions, neurologic disease of lower extremities, inflammation, infection, endocrine or metabolic disease, drug or alcohol abuse, pregnancy, and history of cancer. Finally, we describe emerging tissue engineering and regenerative approaches that might foster cartilage repair in these challenging environments. The identified criteria exclude a majority of the affected population from treatment, and thus greater focus must be placed on these emerging cartilage regeneration techniques to treat patients with the challenging “red knee”.

Differential effects of type 1 diabetes mellitus and subsequent osteoblastic β-catenin activation on trabecular and cortical bone in a mouse model

Type 1 diabetes mellitus (T1DM) is a pathological condition associated with osteopenia. WNT/β-catenin signaling is implicated in this process. Trabecular and cortical bone respond differently to WNT/β-catenin signaling in healthy mice. We investigated whether this signaling has different effects on trabecular and cortical bone in T1DM. We first established a streptozotocin-induced T1DM mouse model and then constitutively activated β-catenin in osteoblasts in the setting of T1DM (T1-CA). The extent of bone loss was greater in trabecular bone than that in cortical bone in T1DM mice, and this difference was consistent with the reduction in the expression of β-catenin signaling in the two bone compartments. Further experiments demonstrated that in T1DM mice, trabecular bone showed lower levels of insulin-like growth factor-1 receptor (IGF-1R) than the levels in cortical bone, leading to lower WNT/β-catenin signaling activity through the inhibition of the IGF-1R/Akt/glycogen synthase kinase 3β (GSK3β) pathway. After β-catenin was activated in T1-CA mice, the bone mass and bone strength increased to substantially greater extents in trabecular bone than those in cortical bone. In addition, the cortical bone of the T1-CA mice displayed an unexpected increase in bone porosity, with increased bone resorption. The downregulated expression of WNT16 might be responsible for these cortical bone changes. In conclusion, we found that although the activation of WNT/β-catenin signaling increased the trabecular bone mass and bone strength in T1DM mice, it also increased the cortical bone porosity, impairing the bone strength. These findings should be considered in the future treatment of T1DM-related osteopenia.

Foot and Ankle Surgery: Common Problems and Solutions

Participation in sports activity has increased significantly during the last several decades. This phenomenon has exposed orthopedic sports medicine surgeons to new challenges regarding the diagnosis and management of common sport-related injuries. Arthroscopy is becoming more commonly used in many of the surgical procedures for these injuries and carries the risk of complications. Wound and nerve complications make up the bulk of complications in most procedures. This article describes these complications associated with the common surgical procedures related to foot and ankle sport-related injuries and how to address and prevent them.

Review: The relationship of hemoglobin A1c to postoperative surgical risk with an emphasis on joint replacement surgery

Patients with diabetes mellitus are known to have a high risk of postoperative complications, including infections, impaired wound healing, cardiovascular events, venous thromboembolism, and mortality. Because hyperglycemia has been thought to mediate this risk, there is a clinical propensity for improving glycemic control, as assessed by hemoglobin A1c (HbA1c) level, prior to proceeding with elective surgery, particularly joint replacement surgery. However, it is not established whether chronic poor glycemic control, indicated by elevated HbA1c levels, predicts increased risk of postoperative complications. The benefit of improving glycemic control must be weighed against risks of delaying necessary elective surgery, such as joint replacement surgery, which risks may include negative impact on long-term glycemic control. Thus, we review the current evidence to determine the relationship between HbA1c and postoperative surgical risk, especially on joint replacement surgery.

Hyperglycemia is Associated with Surgical Site Infections among General and Vascular Surgery Patients

Surgical site infection (SSI) is a common cause of morbidity in general and vascular surgery patients. There is inconsistent evidence on the association of glycemic status with SSI, and its utility in predicting and mitigating SSI. General and vascular surgery patients at a public teaching hospital had the following markers of glycemic status prospectively collected: preoperative hemoglobin A1c (HbA1c) and capillary blood glucose (cBG, within six months before surgery), perioperative cBG (within 24 hours before surgery), and postoperative cBG (peak value up to 48 hours after surgery). Patient records were assessed for SSI within 30 days of surgery. Over a two-month period, 229 patients underwent surgery. The overall SSI rate was 9.6 per cent. Preoperative HbA1c >7 per cent and postoperative cBG ≥180 mL/dL occurred in 25.9 and 27.0 per cent of patients, respectively. Preoperative HbA1c >7 per cent was significantly associated with SSI [odds ratio (OR) 2.26, 80 per cent confidence interval (CI) 1.01–5.07], as was postoperative cBG ≥180 mg/dL (OR 2.12, 80 per cent CI 1.02–4.41). There was no significant correlation between preoperative or perioperative cBG and SSI. In conclusion, SSI and hyperglycemia were frequent among the study population, and positively associated. Glycemic status may be used for improved preoperative risk assessment, and as it is potentially mutable, to reduce SSI.

Hemoglobin A1c as a Predictor of Postoperative Infection Following Elective Forefoot Surgery

BACKGROUND

There remains little evidence to support a perioperative hemoglobin A_1c (HbA_1c) level that could serve as a threshold for a significantly increased risk of postoperative surgical site infection (SSI) following forefoot surgery.

METHODS

A national database was queried for patients who underwent elective forefoot surgery with diabetes. Patients with a perioperative HbA_1c level within 3 months of surgery were identified and stratified based on HbA_1c level in 0.5 mg/dL increments. The incidence of SSI was determined by either a diagnosis or procedure for SSI within 1 year and a receiver operating characteristic (ROC) curve and area under the curve (AUC) analysis was performed to determine an optimal threshold value of HbA_1c.

RESULTS

A total of 4630 patients who underwent forefoot surgery with diabetes with a perioperative HbA_1c were included. The rate of SSI ranged from 2.3% to 11.8%. The inflection point of the ROC curve corresponded to an HbA_1c level above 7.5 mg/dL ( P < .0001; 95% confidence interval [CI] = 0.58-0.67; AUC = 0.631; specificity = 75%; sensitivity = 46%). After multivariate analysis, patients with an HbA_1c level of 7.5 mg/dL or greater had a significantly higher risk for postoperative wound infection compared to patients below this threshold (OR = 1.92; 95% CI = 1.5-2.4; P < .0001).

CONCLUSIONS

The risk of postoperative SSI following forefoot surgery increased as the perioperative HbA_1c increased. ROC analysis determined that a perioperative HbA_1c above 7.5 mg/dL could serve as a threshold for a significantly increased risk of postoperative SSI following forefoot surgery.

LEVEL OF EVIDENCE

Level III, comparative series.

Osteoclasis for the Treatment of Recalcitrant Diabetic Forefoot Ulceration: A Case Study

Recurrence after diabetic foot ulceration is a common occurrence after healing. Curative surgery has been suggested to reduce the incidence of recurrent ulcerations. Osteoclasis is a simple procedure used to fracture the metatarsal head in attempt to reduce pressure under the affected metatarsal without transferring excessive pressure to adjacent metatarsals. We present a case study of a 65-year-old diabetic male with multiple attempts to heal and maintain a healed ulceration who underwent an osteoclasis procedure. Following this patient for 3 years (until time of death), no recurrent or new ulcerations had occurred. Further studies should be conducted to identify if this result is reproducible prior to widespread use.

Association between glycaemic control and common infections in people with Type 2 diabetes: a cohort study

AIM

To investigate the impact of glycaemic control on infection incidence in people with Type 2 diabetes.

METHODS

We compared infection rates during 2014 in people with Type 2 diabetes and people without diabetes in a large primary care cohort in the UK (the Royal College of General Practitioners Research and Surveillance Centre database). We performed multilevel logistic regression to investigate the impact of Type 2 diabetes on presentation with infection, and the effect of glycaemic control on presentation with upper respiratory tract infections, bronchitis, influenza-like illness, pneumonia, intestinal infectious diseases, herpes simplex, skin and soft tissue infections, urinary tract infections, and genital and perineal infections. People with Type 2 diabetes were stratified by good [HbA_1c < 53 mmol/mol (< 7%)], moderate [HbA_1c 53-69 mmol/mol (7-8.5%)] and poor [HbA_1c > 69 mmol/mol (> 8.5%)] glycaemic control using their most recent HbA_1c concentration. Infection incidence was adjusted for important sociodemographic factors and patient comorbidities.

RESULTS

We identified 34 278 people with Type 2 diabetes and 613 052 people without diabetes for comparison. The incidence of infections was higher in people with Type 2 diabetes for all infections except herpes simplex. Worsening glycaemic control was associated with increased incidence of bronchitis, pneumonia, skin and soft tissue infections, urinary tract infections, and genital and perineal infections, but not with upper respiratory tract infections, influenza-like illness, intestinal infectious diseases or herpes simplex.

CONCLUSIONS

Almost all infections analysed were more common in people with Type 2 diabetes. Infections that are most commonly of bacterial, fungal or yeast origin were more frequent in people with worse glycaemic control.

American College of Foot and Ankle Surgeons® Clinical Consensus Statement: Perioperative Management

A wide range of factors contribute to the complexity of the management plan for an individual patient, and it is the surgeon's responsibility to consider the clinical variables and to guide the patient through the perioperative period. In an effort to address a number of important variables, the American College of Foot and Ankle Surgeons convened a panel of experts to derive a clinical consensus statement to address selected issues associated with the perioperative management of foot and ankle surgical patients.

Association between elevated pre-operative glycosylated hemoglobin and post-operative infections after non-emergent surgery

Background

A chronic state of impaired glucose metabolism affects multiple components of the immune system, possibly leading to an increased incidence of post-operative infections. Such infections increase morbidity, length of stay, and overall cost. This study evaluates the correlation between elevated pre-operative glycosylated hemoglobin (HbA1c) and post-operative infections.

Study design

Adult patients undergoing non-emergent procedures across all surgical subspecialties from January 2010 to July 2014 had a preoperative HbA1c measured as part of their routine pre-surgical assessment. 2200 patient charts (1100 < 6.5% HbA1c and1100 ≥ 6.5% HbA1c) were reviewed for evidence of post-operative infection (superficial surgical site infection, deep wound/surgical space abscess, pneumonia, and/or urinary tract infection as defined by Centers for Disease Control criteria) within 30 days of surgery.

Results

Patients with HbA1c < 6.5% and those with HbA1c ≥ 6.5% showed no statistically significant difference in overall infection rate (3.8% in the HbA1c < 6.5% group vs. 4.5% in the HbA1c ≥ 6.5% group, p = 0.39). Both linear regression and multivariate analysis did not identify HbA1c as an individual predictor of infection. Elevated HbA1c was, however, predictive of significantly increased risk of post-operative infection when associated with increased age (≥81 years of age) or dirty wounds.

Conclusions

The risk factors of post-operative infection are multiple and likely synergistic. While pre-operative HbA1c level is not independently associated with risk of post-operative infection, there are scenarios and patient subgroups where pre-operative HbA1c is useful in predicting an increased risk of infectious complications in the post-operative period.

•

This study reviews the impact of pre-operative HbA1c across many specialties undergoing elective surgery.

•

The risk factors of post-operative infection are multiple and likely synergistic.

•

Elevated serum HbA1c is not independently associated with an increased risk of post-operative infection.

Skeletal Metabolism, Fracture Risk, and Fracture Outcomes in Type 1 and Type 2 Diabetes

Fracture risk is significantly increased in both type 1 and type 2 diabetes, and individuals with diabetes experience worse fracture outcomes than normoglycemic individuals. Factors that increase fracture risk include lower bone mass in type 1 diabetes and compromised skeletal quality and strength despite preserved bone density in type 2 diabetes, as well as the effects of comorbidities such as diabetic macro- and microvascular complications. In this Perspective, we assess the developing scientific knowledge regarding the epidemiology and pathophysiology of skeletal fragility in patients with diabetes and the emerging data on the prediction, treatment, and outcomes of fractures in individuals with type 1 and type 2 diabetes.

Association Between Hemoglobin A1c and Surgical Morbidity in Elective Foot and Ankle Surgery

The current guidelines for the management of diabetes in adults have recommended strict glycemic control, with a target hemoglobin A1c of 7.0%. Increasing evidence has shown that strict glycemic control decreases the risk of developing the organ system complications associated with diabetes. Elevated hemoglobin A1c levels have been theorized as a risk factor for complications after elective foot and ankle surgery. To test this hypothesis, we reviewed the Department of Veterans Affairs national administrative and clinical databases for a 6-year period (January 2008 to December 2013). During this period, 21,854 diabetic patients had a recorded hemoglobin A1c measurement within 1 year before undergoing elective foot and ankle surgery. We then identified those patients who had experienced postoperative complications within 30 days of elective foot or ankle surgery using the International Classification of Diseases, ninth revision, codes. The complications were classified into 4 groups: infection, wound healing, mechanical failure, and cardiovascular/pulmonary. The overall 30-day postoperative complication rate was 3.2%. The most common complication was infection (42.3%), followed by mechanical failure (33.4%), cardiovascular/pulmonary (18.4%), and wound healing (5.8%). The average hemoglobin A1c of a patient who had experienced a complication was 6.29% compared with 6.11% for a patient who had not experienced 1 of the 4 complications (p < .001). Logistic regression analysis revealed that for each 1% increase in hemoglobin A1c, the odds of developing a complication increased by 5%. More significant was the 1.78 times increased risk of developing a complication for patients with neuropathy (95% confidence interval 1.45 to 2.20; p = .0001). Even more notable was the associated risk of complications after elective foot and ankle surgery for those patients with comorbid conditions. Patients demonstrated 3.08 times the risk of developing a complication when the patient had 2 to 3 identified comorbid conditions associated with diabetes mellitus (95% confidence interval 2.42 to 3.92; p = .0001). The present retrospective observational investigation has demonstrated glycemic control influences the postoperative complication rates in elective foot and ankle surgery. However, the data collected from the present study have also demonstrated that the complication rates are multifactorial. Comorbid conditions and the presence of peripheral neuropathy also play a significant role in determining a patient's risk of complications after elective foot and ankle surgery.

Topically Applied Vancomycin Powder Reduces the Rate of Surgical Site Infection in Diabetic Patients Undergoing Foot and Ankle Surgery

BACKGROUND

The purpose of this study was to evaluate the efficacy of topically applied vancomycin powder in reducing the rate of surgical site infections (SSIs) in patients with diabetes mellitus (DM) undergoing foot and ankle surgery.

METHODS

Eighty-one patients with DM who underwent reconstructive surgery of a foot and/or ankle deformity and/or trauma and who received topically applied vancomycin were matched to 81 patients with DM who did not receive topically applied vancomycin. The mean age was 60.6 years in the vancomycin group and 59.4 years in the control group (P < .05). The 2 groups were similar with regard to gender, body mass index, duration of DM, short-term and longer term glycemic control, and length of surgery.

RESULTS

The overall likelihood of SSI was decreased by 73% in patients who received topically applied vancomycin (odds ratio [OR], 0.267; 95% CI, 0.089-0.803; P = .0188). The rate of superficial infection was not significantly different between the 2 groups (OR, 0.400; 95% CI, 0.078-2.062; P = .2734); however, deep infections were 80% less likely in patients who received vancomycin powder (OR, 0.200; 95% CI, 0.044-0.913; P = .0377).

CONCLUSION

High-risk diabetic patients undergoing foot and ankle surgery were notably less likely to develop an SSI with the use of topically applied vancomycin powder in the surgical wound, particularly with regard to deep infections. Topically applied vancomycin was associated with a very low rate of complications and was inexpensive ($5 per 1000 mg). Based on this study, foot and ankle surgeons may consider applying 500 to 1000 mg of vancomycin powder prior to skin closure in diabetic patients who are not allergic to vancomycin.

LEVEL OF EVIDENCE

Level III, retrospective case control series.

The impact of diabetes mellitus on outcomes of endoscopic sinus surgery: a nested case-control study

BACKGROUND

Given the immune impairment associated with diabetes mellitus (DM), its impact on chronic rhinosinusitis (CRS) is a potentially relevant concern; however, it has not been well-studied. A single retrospective study reported worse postoperative quality of life outcomes in DM patients with CRS. Our study evaluated the effect of comorbid DM on outcomes of endoscopic sinus surgery (ESS) using a prospective study design.

METHODS

Using a multicentered, prospective cohort of patients (n = 437) undergoing ESS for recalcitrant CRS, a nested case-control comparison was performed between 20 adult DM patients (cases) and 20 non-DM patients (controls), matched 1:1 for age and Lund-Mackay computed tomography (CT) scores. Outcome measures included 22-item Sinonasal Outcome Test (SNOT-22), Rhinosinusitis Disability Index (RSDI), Patient Health Questionnaire (PHQ-2), and Brief Smell Identification Test (BSIT).

RESULTS

Mean follow-up was similar between cases (mean ± standard deviation: 12.6 ± 6.0 months) and controls (12.9 ± 5.9 months; p = 0.862). All preoperative scores were statistically equivalent between DM and non-DM cohorts. Both cohorts showed significant post-ESS improvement in SNOT-22 (p = 0.001) and RSDI scores (p < 0.001), and no significant change in PHQ-2 or BSIT scores. The magnitude of score changes was statistically equivalent between the 2 cohorts for all outcome measures with no differences in postoperative score changes between insulin-dependent DM patients and those managed by oral hypoglycemics or dietary restriction (p ≥ 0.444).

CONCLUSION

DM patients with CRS experience similar degrees of symptomatic benefit from ESS compared to controls. Insulin dependence does not appear to adversely affect surgical outcome but a larger cohort would better assess the effect of DM type and control on surgical outcomes in CRS.