Haemoglobin A1c (HbA1C) in Non-diabetic and Diabetic Vascular Patients. Is HbA1C an Independent Risk Factor and Predictor of Adverse Outcome?

Elevated Hb A1C level and revisional bariatric surgery complications

BACKGROUND

Elevated Hb A1C is a modifiable risk factor for postoperative complications. However, in bariatric surgery, as published by our group and others, elevated preoperative Hb A1C may not be associated with increased postoperative complications. Previous literature has focused on primary bariatric surgery and has excluded the higher-risk revisional surgery cohort.

OBJECTIVE

To assess the impact of Hb A1C on early postoperative outcomes in patients requiring revisional bariatric surgery.

SETTING

Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database.

METHODS

We undertook a retrospective review of patients undergoing revisional bariatric surgery between 2017 and 2018 from the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database. Two groups were studied, defined by Hb A1C cutoff, ≤8% versus >8% and ≤10% versus >10%. Early postoperative complications were compared at each threshold, with the primary outcome defined as a composite of all complications. Propensity score matching (PSM) was used with one-to-one matching for covariates, and the complication rates before and after PSM were calculated and assessed by Fisher's exact test and conditional logistic regression, respectively.

RESULTS

A total of 16,234 patients had undergone revisional bariatric surgery. After PSM, elevated Hb A1C was not associated with worse outcomes. No significant difference was seen in the composite outcomes for Hb A1C ≤8% versus Hb A1C >8% (P = .22) or for patients with Hb A1C ≤10% versus Hb A1C >10% (P < .46). There were no differences in individual outcomes such as surgical-site infections, cardiopulmonary complications, or readmissions/reinterventions.

CONCLUSION

In this study of revisional bariatric patients, elevated Hb A1C >8% or >10% was not associated with increased postoperative complications. Prospective studies are needed to investigate this further.

The Effects of Preoperative Glycaemic Control (HbA1c) on Bariatric and Metabolic Surgery Outcomes: Data from a Tertiary-Referral Bariatric Centre in the UK

BACKGROUND

Current recommendations advocate the achievement of an optimal glucose control (HbA1c < 69 mmol/mol) prior to elective surgery to reduce risks of peri- and post-operative complications, but the relevance for this glycaemic threshold prior to Bariatric Metabolic Surgery (BMS) following a specialist weight management programme remains unclear.

METHODS

We undertook a retrospective cohort study of patients with type 2 diabetes mellitus (T2DM) who underwent BMS over a 6-year period (2016-2022) at a regional tertiary referral following completion of a specialist multidisciplinary weight management. Post-operative outcomes of interest included 30-day mortality, readmission rates, need for Intensive Care Unit (ICU) care and hospital length of stay (LOS) and were assessed according to HbA1c cut-off values of < 69 (N = 202) and > 69 mmol/mol (N = 67) as well as a continuous variable.

RESULTS

A total of 269 patients with T2D were included in this study. Patients underwent primary Roux en-Y gastric bypass (RYGB, n = 136), Sleeve Gastrectomy (SG, n = 124), insertion of gastric band (n = 4) or one-anastomosis gastric bypass (OAGB, n = 4). No significant differences in the rates of complications were observed between the two groups of pre-operative HbA1c cut-off values. No HbA1c threshold was observed for glycaemic control that would affect the peri- and post-operative complications following BMS.

CONCLUSIONS

We observed no associations between pre-operative HbA1C values and the risk of peri- and post-operative complications. In the context of a specialist multidisciplinary weight management programme, optimising pre-operative HbA1C to a recommended target value prior to BMS may not translate into reduced risks of peri- and post-operative complications.

Investigating glycemic control in patients undergoing lower extremity bypass within an enhanced recovery pathway at a single institution

BACKGROUND

Enhanced recovery pathways (ERPs) aim to lower perioperative stress to facilitate recovery. Limited fasting combined with carbohydrate loading is a common ERP element. The effect of limited fasting has not been elucidated in patients with diabetes. Given the known deleterious effects of poor glycemic control in the perioperative period, such as increased rates of surgical site infection, the associations of preoperative limited fasting with perioperative glycemic control and early outcomes after lower extremity bypass (LEB) were investigated.

METHODS

A single institutional retrospective review of patients who underwent infrainguinal LEB from 2016 to 2022 was performed. The ERP was initiated in May 2018. Patients were stratified by diabetes diagnosis and preoperative hemoglobin A1C (HbA1C) levels. Perioperative glycemic control was compared between the limited fasting and traditional fasting patients (nil per os at midnight). Limited fasting was defined as a clear liquid diet until 2 hours before surgery with recommended carbohydrate loading consisting of 400 cc of a clear sports drink (approximately 30 g of carbohydrates). All limited fasting patients were within the ERP. Early perioperative hyperglycemia (EPH) was defined as blood glucose of >180 mg/dL within the first 24 hours of surgery. Perioperative outcomes such as surgical site infection, readmission, reinterventions, and complications were also compared.

RESULTS

A total of 393 patients were included (limited fasting patients N = 135; traditional fasting patients N = 258). A trend toward EPH was seen in all limited fasting groups. Evaluating limited fasting within diabetic patients revealed that 74.5% of limited fasting-diabetic patients had EPH compared with 49.6% of traditional fasting-diabetic patients (P = .001). When stratified by the HbA1C level, a significantly higher rate of EPH was seen in the HbA1c >8.0% groups, with 90.5% in the limited fasting patients compared with 67.9% in traditional fasting patients (P = .05). Limited fasting-diabetic patients experience a longer postoperative length of stay at 5.0 days (interquartile range: 3, 9) vs 4.0 days (2, 6) in nondiabetic patients (P = .016).

CONCLUSIONS

ERP limited fasting was associated with early perioperative hyperglycemia after LEB, particularly in patients with HbA1C >8.0%. Due to the high prevalence of diabetic patients undergoing LEB under ERP, the role of limited fasting and common glycemic elements of ERP may need to be re-evaluated in this subpopulation.

Peri-operative management of diabetes mellitus - A survey of current practices among Indian anesthesiologists

Background and Aims

Increased burden of diabetes in India has resulted in a spurt in the number of patients with diabetes posted for surgeries. The paucity of national guidelines can lead to marked practice variations in the peri-operative management of diabetes. This survey intends to discern current peri-operative practices among anesthesiologists working in medical colleges, tertiary care government, and private health care institutes of the country.

Material and Methods

An anonymous online survey comprising of 25 closed-ended questions was conducted using Google Forms® and disseminated through social media, emails, and messaging platforms. The questionnaire dealt primarily with the peri-operative management of diabetes in patients scheduled for elective surgery. The survey was conducted over a period of 1 month and targeted anesthesia resident trainees with more than 1-year experience, senior residents, and consultants working in India.

Results

Statistically significant difference was observed between the three types of health facilities with respect to prior evaluation for diabetes (P = 0.007), prioritizing operative list (P = 0.006), hospital encouragement of day care surgery (P < 0.001), glycated hemoglobin level (HbA1c) level >8.5 for postponement of surgery (P < 0.05), insulin infusion preference (P < 0.001), hourly intra-operatively capillary blood glucose (CBG) assessment (P = 0.021), and avoiding peri-operative use of Ringer's lactate (RL) (P = 0.025).

Conclusion

This survey primarily highlights the lack of prioritizing the operative list, early discontinuation of metformin, and reduced tendency to consider diabetics for day care surgeries.

Diet and Exercise Exert a Differential Effect on Glucose Metabolism Markers According to the Degree of NAFLD Severity

BACKGROUND

Non-Alcoholic Fatty Liver Disease (NAFLD) and Type 2 Diabetes (T2D) are highly prevalent diseases worldwide. Insulin Resistance (IR) is the common denominator of the two conditions even if the precise timing of onset is unknown. Lifestyle change remains the most effective treatment to manage NAFLD. This study aimed to estimate the effect of the Low Glycemic Index Mediterranean Diet (LGIMD) and exercise (aerobic and resistance) over a one-year period on the longitudinal trajectories of glucose metabolism regulatory pathways.

MATERIALS AND METHODS

In this observational study, 58 subjects (aged 18-65) with different degrees of NAFLD severity were enrolled by the National Institute of Gastroenterology-IRCCS "S. de Bellis", to follow a 12-month program of combined exercise and diet.

RESULTS

The mean age was 55 ± 7 years old. Gender was equally distributed among NAFLD categories. There was a statistically significant main effect of time for glycosylated hemoglobin (Hb1Ac) over the whole period (-5.41, 95% CI: -7.51; -3.32). There was a steady, statistically significant decrease of HbA1c in participants with moderate and severe NAFLD whereas this effect was observed after the 9th month in those with mild NAFLD.

CONCLUSIONS

The proposed program significantly improves glucose metabolism parameters, especially HbA1c.

The Quality of Preoperative Glycemic Control Predicts Insulin Sensitivity During Major Upper Abdominal Surgery: A Case-Control Study

Objective

To examine the association of the quality of preoperative glycemic control and insulin sensitivity during major upper abdominal surgery.

Background

In cardiac surgery, glycated hemoglobin A1c (HbA1c), an indicator of glycemic control during the preceding 3 months, correlated with intraoperative insulin sensitivity. Furthermore, insulin resistance showed a significant association with adverse clinical outcomes.

Methods

This study is a post hoc exploratory analysis of a randomized controlled trial in patients undergoing elective hepatectomy and receiving the hyperinsulinemic-normoglycemic clamp (HNC) as a potential intervention to reduce surgical site infections (ClinicalTrials.gov NCT01528189). Immediately before skin incision, the HNC was initiated by infusing insulin at the rate of 2 mU/kg/min. Dextrose was administered at rates titrated to maintain normoglycemia (4.0-6.0 mmol/L). The average of 3 consecutive dextrose infusion rates during steady state was used as a measure of insulin sensitivity. Primary outcome was the relationship between preoperative HbA1c and insulin sensitivity during surgery. Secondary outcomes were the associations of insulin sensitivity with the patient's body mass index (BMI) and postoperative morbidity.

Results

Thirty-four patients were studied. HbA1c (Y = -0.52X + 4.8, P < 0.001, R2 = 0.29), BMI (Y = -0.12X + 5.0, P < 0.001, R2 = 0.43) showed negative correlations with insulin sensitivity. The odds ratio of postoperative complications within 30 days of surgery for every increase in insulin sensitivity by 1 mg/kg/min was 0.22 (95% confidential interval, 0.06-0.59; P = 0.009).

Conclusions

We demonstrate significant associations of the quality of preoperative glycemic control and body mass index with insulin sensitivity during hepatectomy. The degree of insulin resistance correlated with postoperative morbidity.

An Examination of Whether Diabetes Control and Treatments Are Associated With Change in Frailty Index Across 8 Years: An Ancillary Exploratory Study From the Action for Health in Diabetes (Look AHEAD) Trial

OBJECTIVE

The aim of this study was to describe cross-sectional and longitudinal associations between glycated hemoglobin (HbA1c) levels and strategies to control type 2 diabetes with baseline levels and 8-year changes in a deficit accumulation frailty index (FI), a commonly used marker of biological aging.

RESEARCH DESIGN AND METHODS

We conducted exploratory analyses from 4,169 participants, aged 45-76 years, who were followed in the Action for Health in Diabetes (Look AHEAD) randomized controlled clinical trial, pooling data across intervention groups. We related baseline and 8-year levels of HbA1c with FI scores using analyses of variance and covariance. Associations between 8-year changes in FI and the use of diabetes medication classes and weight changes were assessed with control for HbA1c levels. Inverse probability weighting was used to assess bias associated with differential follow-up.

RESULTS

Baseline and average HbA1c levels over time of <7%, as compared with ≥8%, were associated with less increase in FI scores over 8 years (both P ≤ 0.002). After adjustment for HbA1c, use of metformin and weight loss >5% were independently associated with slower increases in frailty.

CONCLUSIONS

Lower HbA1c levels among individuals with diabetes are associated with slower biological aging as captured by a deficit accumulation FI. Strategies to control diabetes through weight loss or metformin use may also slow aging.

Elevated hemoglobin A1c level and bariatric surgery complications

INTRODUCTION

In cardiac and orthopedic surgery, elevated glycosylated hemoglobin (HbA1c) is a modifiable risk factor for postoperative complications. However, in bariatric surgery, there is insufficient evidence to assess the effectiveness of preoperative HbA1c assessment and its association with postoperative complications. The objective of this study was to assess the impact of HbA1c on early postoperative outcomes in bariatric surgery patients.

METHODS

Patients who underwent laparoscopic sleeve gastrectomy and laparoscopic Roux-En-Y Gastric Bypass between 2017 and 2018 were selected for a retrospective review from the metabolic and bariatric surgery accreditation and quality improvement program (MBSAQIP) database. The study population of 118,742 patients was analyzed for our primary outcome which was defined as a composite of any postoperative complications occurring within 30 days. Two groups were defined by HbA1c cutoff: comparison point A (≤ 8% vs > 8%) and comparison point B (≤ 10% vs > 10%). Procedure-related complications were also examined on subgroup analysis. Propensity score matching (PSM) was used with one-to-one matching. The complication rates before and after PSM were calculated and assessed by Fisher's exact test and conditional logistic regression, respectively.

RESULTS

After PSM, demographic and clinical characteristics were all balanced and elevated HbA1C was not associated with worse outcomes. After adjusting for underlying comorbidities, there was no statistically significant difference seen in the composite outcome for comparison point A HbA1C ≤ 8 and HbA1C > 8 (p = 0.22). For comparison point B, patients with HbA1C ≤ 10 had more composite complications compared to patients with HbA1C > 10 (p < 0.001). Also, on subgroup analysis after PSM for procedure-specific complications, patients above the cutoff threshold of 8 did not have worsened composite outcomes (p = 0.58 and 0.89 for sleeve and bypass, respectively). Again, at cutoff threshold of 10, patients in HbA1C ≤ 10 had more composite complications (p = 0.001 and 0.007 for sleeve and bypass, respectively).

CONCLUSION

In this study of bariatric patients, elevated HbA1c > 8% or 10% was not associated with increased postoperative complications. HbA1c lower than 10% was associated with some types of adverse outcomes in this bariatric dataset. More studies are needed to investigate these findings further. A high HbA1c alone may not disqualify a patient from proceeding with bariatric surgery.

Management of Hyperglycemia in Hospitalized Adult Patients in Non-Critical Care Settings: An Endocrine Society Clinical Practice Guideline

BACKGROUND

Adult patients with diabetes or newly recognized hyperglycemia account for over 30% of noncritically ill hospitalized patients. These patients are at increased risk for adverse clinical outcomes in the absence of defined approaches to glycemic management.

OBJECTIVE

To review and update the 2012 Management of Hyperglycemia in Hospitalized Patients in Non-Critical Care Settings: An Endocrine Society Clinical Practice Guideline and to address emerging areas specific to the target population of noncritically ill hospitalized patients with diabetes or newly recognized or stress-induced hyperglycemia.

METHODS

A multidisciplinary panel of clinician experts, together with a patient representative and experts in systematic reviews and guideline development, identified and prioritized 10 clinical questions related to inpatient management of patients with diabetes and/or hyperglycemia. The systematic reviews queried electronic databases for studies relevant to the selected questions. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology was used to assess the certainty of evidence and make recommendations.

RESULTS

The panel agreed on 10 frequently encountered areas specific to glycemic management in the hospital for which 15 recommendations were made. The guideline includes conditional recommendations for hospital use of emerging diabetes technologies including continuous glucose monitoring and insulin pump therapy; insulin regimens for prandial insulin dosing, glucocorticoid, and enteral nutrition-associated hyperglycemia; and use of noninsulin therapies. Recommendations were also made for issues relating to preoperative glycemic measures, appropriate use of correctional insulin, and diabetes self-management education in the hospital. A conditional recommendation was made against preoperative use of caloric beverages in patients with diabetes.

CONCLUSION

The recommendations are based on the consideration of important outcomes, practicality, feasibility, and patient values and preferences. These recommendations can be used to inform system improvement and clinical practice for this frequently encountered inpatient population.

A Systematic Review Supporting the Endocrine Society Clinical Practice Guideline for the Management of Hyperglycemia in Adults Hospitalized for Noncritical Illness or Undergoing Elective Surgical Procedures

CONTEXT

Individuals with diabetes or newly recognized hyperglycemia account for over 30% of noncritically ill hospitalized patients. Management of hyperglycemia in these patients is challenging.

OBJECTIVE

To support development of the Endocrine Society Clinical Practice Guideline for management of hyperglycemia in adults hospitalized for noncritical illness or undergoing elective surgical procedures.

METHODS

We searched several databases for studies addressing 10 questions provided by a guideline panel from the Endocrine Society. Meta-analysis was conducted when feasible. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology was used to assess certainty of evidence.

RESULTS

We included 94 studies reporting on 135 553 patients. Compared with capillary blood glucose, continuous glucose monitoring increased the number of patients identified with hypoglycemia and decreased mean daily blood glucose (BG) (very low certainty). Data on continuation of insulin pump therapy in hospitalized adults were sparse. In hospitalized patients receiving glucocorticoids, combination neutral protamine hagedorn (NPH) and basal-bolus insulin was associated with lower mean BG compared to basal-bolus insulin alone (very low certainty). Data on NPH insulin vs basal-bolus insulin in hospitalized adults receiving enteral nutrition were inconclusive. Inpatient diabetes education was associated with lower HbA1c at 3 and 6 months after discharge (moderate certainty) and reduced hospital readmissions (very low certainty). Preoperative HbA1c level < 7% was associated with shorter length of stay, lower postoperative BG and a lower number of neurological complications and infections, but a higher number of reoperations (very low certainty). Treatment with glucagon-like peptide-1 agonists or dipeptidyl peptidase-4 inhibitors in hospitalized patients with type 2 diabetes and mild hyperglycemia was associated with lower frequency of hypoglycemic events than insulin therapy (low certainty). Caloric oral fluids before surgery in adults with diabetes undergoing surgical procedures did not affect outcomes (very low certainty). Counting carbohydrates for prandial insulin dosing did not affect outcomes (very low certainty). Compared with scheduled insulin (basal-bolus or basal insulin + correctional insulin), correctional insulin was associated with higher mean daily BG and fewer hypoglycemic events (low certainty).

CONCLUSION

The certainty of evidence supporting many hyperglycemia management decisions is low, emphasizing importance of shared decision-making and consideration of other decisional factors.

Predictive Value of Glycosylated Hemoglobin for Post-operative Acute Kidney Injury in Non-cardiac Surgery Patients

Objective

Recent studies have indicated that patients (both with and without diabetes) with elevated hemoglobin A1c (HbA1c) have a higher rate of acute kidney injury (AKI) following cardiac surgery. However, whether HbA1c could help to predict post-operative AKI in patients after non-cardiac surgery is less clear. This study aims to explore the predictive value of pre-operative HbA1c for post-operative AKI in non-cardiac surgery.

Methods

We reviewed the medical records of patients (≥ 18 years old) who underwent non-cardiac surgery between 2011 and 2020. Patient-related variables, including demographic and laboratory and procedure-related information, were collected, and univariable and multivariable logistic regression analyses were performed to determine the association of HbA1c with AKI. The area under the receiver operating curve (AUC), net reclassification improvement index (NRI), and integrated discriminant improvement index (IDI) were used to evaluate the predictive ability of the model, and decision curve analysis was used to evaluate the clinical utility of the HbA1c-added predictive model.

Results

A total of 3.3% of patients (94 of 2,785) developed AKI within 1 week after surgery. Pre-operative HbA1c was an independent predictor of AKI after adjustment for some clinical variables (OR comparing top to bottom quintiles 5.02, 95% CI, 1.90 to 13.24, P < 0.001 for trend; OR per percentage point increment in HbA1c 1.20, 95% CI, 1.07 to 1.33). Compared to the model with only clinical variables, the incorporation of HbA1c increased the model fit, modestly improved the discrimination (change in area under the curve from 0.7387 to 0.7543) and reclassification (continuous net reclassification improvement 0.2767, 95% CI, 0.0715 to 0.4818, improved integrated discrimination 0.0048, 95% CI, -5e-04 to 0.0101) of AKI and non-AKI cases, NRI for non-AKI improvement 0.3222, 95% CI, 0.2864 to 0.3580 and achieved a higher net benefit in decision curve analysis.

Conclusion

Elevated pre-operative HbA1c was independently associated with post-operative AKI risk and provided predictive value in patients after non-cardiac surgery. HbA1c improved the predictive power of a logistic regression model based on traditional clinical risk factors for AKI. Further prospective studies are needed to demonstrate the results and clinical application.

Diabetes mellitus and perioperative outcomes: a scoping review of the literature

BACKGROUND

Diabetes mellitus (DM) is frequently encountered in the perioperative period. DM may increase the risk of adverse perioperative outcomes owing to the potential vascular complications of DM. We conducted a scoping review to examine the association between DM and adverse perioperative outcomes.

METHODS

A systematic search strategy of the published literature was built and applied in multiple databases. Observational studies examining the association between DM and adverse perioperative outcomes were included. Abstract screening determined full texts suitable for inclusion. Core information was extracted from each of the included studies including study design, definition of DM, type of DM, surgical specialties, and outcomes. Only primary outcomes are reported in this review.

RESULTS

The search strategy identified 2363 records. Of those, 61 were included and 28 were excluded with justification. DM was mostly defined by either haemoglobin A1c (HbA1c) or blood glucose values (19 studies each). Other definitions included 'prior diagnosis' or use of medication. In 17 studies the definition was unclear. Type 2 DM was the most frequently studied subtype. Five of seven studies found DM was associated with mortality, 5/13 reported an association with 'complications' (as a composite measure), and 12/17 studies found DM was associated with 'infection'. Overall, 33/61 studies reported that DM was associated with the primary outcome measure.

CONCLUSION

Diabetes mellitus is inconsistently defined in the published literature, which limits the potential for pooled analysis. Further research is necessary to determine which cohort of patients with DM are most at risk of adverse postoperative outcomes, and how control influences this association.

Comparison of three different HbA1c measurement methods - the Atellica®CH930, Capillary 3 Tera, and BioRad Variant Turbo II

AIM

HbA1c measurement is very useful for the follow-up and detection of glycemic disorder, since it is easier and faster test and is independent of the patient's fasting status. In this study, we aimed to perform the comparative evaluation of 3 different methods for HbA1c measurement including capillary electrophoresis, immunoturbidimetric assay and high-performance liquid chromatography-HPLC.

MATERIALS AND METHODS

This study comprised 134 leftover whole blood samples obtained from the subjects submitted for routine HbA1c testing. All blood samples were collected in EDTA-containing vacutainer tubes. The HbA1c levels were measured simultaneously using three different methods. Bias estimation, method agreement and concordance between the pairwise methods comparisons were evaluated by Bland-Altman plot and Passing-Bablok regression test.

RESULTS

HbA1c levels ranged from 3.8% to 13.4% and measured by three different methods to make the comparison. The median values of samples based on immunoturbidimetric method (6.05%, IQR = 1.80) were higher than capillary electrophoresis method (5.90%, IQR = 1.80) and HPLC (5.85%, IQR = 1.80) method. The study group was classified into three subgroups based on the HbA1c levels measured with the HPLC method: Group 1 (n = 57) was composed of subjects with HbA1c levels less than 5.7%, Group 2 (n = 35) had HbA1c levels between 5.7% and 6.4%, Group 3 (n = 42) had HbA1c levels equal and more than 6.5%.

CONCLUSION

To our knowledge, there is no study evaluating the HbA1c measurement on the Atellica^® CH 930 Analyzer. We compared the Atellica^®CH930 Analyzer with both HPLC and capillary electrophoresis. The Atellica^®CH930 Analyzer showed acceptable performance and a strong correlation with both mentioned methods.

Preoperative HbA1c and Outcomes Following Lower Extremity Vascular Procedures

OBJECTIVES

Limited data exist evaluating pre-operative hemoglobin A1c (HbA1c) in patients undergoing vascular procedures for peripheral arterial disease (PAD). This study evaluated the relationship of preoperative HbA1c on outcomes after open and endovascular lower extremity (LE) vascular procedures for PAD.

METHODS

We selected patients with PAD admitted for elective LE procedures between September 2008 and December 2015 from the Cerner Health Facts® database using ICD-9-CM diagnosis and procedure codes. Bivariable analysis and multivariable logistic models examined the association of patient characteristics, procedure type, and preoperative HbA1c (normal < 6.5%, high ≥ 6.5%) with postsurgical outcomes that included infection, renal failure, respiratory or cardiac complications, length of stay (LOS), in-hospital mortality, and readmission.

RESULTS

Of 4,087 patients who underwent a LE vascular procedure for PAD, 2,462 (60.2%) had a preoperative HbA1c recorded. The cohort was mostly male (60%), white (73%), and underwent endovascular intervention (77%). Patients with high HbA1c levels were more likely of black race (p < .02) and had significantly higher comorbidities (p < .0001). Elevated HbA1c was associated with diabetes (p < .0001) and cellulitis (p = .05) on unadjusted analysis. Multivariable logistic regression (adjusting for patient, hospital, comorbidity and procedural characteristics) revealed that elevated HbA1c was significantly associated with 30-day readmission (OR = 1.06, 95% CI = 1.00-1.12), but was not associated with the other outcomes. An independent diagnosis of diabetes was not predictive of complications or readmission.

CONCLUSIONS

Historic glucose control, as evidenced by a high preoperative HbA1c level, is not associated with adverse outcome, other than readmission, in patients undergoing LE procedures for PAD. Given the known association of high perioperative glucose levels with poor outcome following vascular procedures, this is suggestive of a more important effect of perioperative, as opposed to chronic, glucose control upon outcome. Thus, we suggest focusing efforts on creating standardized goal-directed guidelines for glucose control in the perioperative period for LE vascular procedures to potentially mitigate complications.

The Role of HbA1c as a Positive Perioperative Predictor of Surgical Site and Other Postoperative Infections: An Explorative Analysis in Patients Undergoing Minor to Major Surgery

Background

Patients with diabetes mellitus type 2 (DM2) inhere impaired peripheral insulin action leading to higher perioperative morbidity and mortality rates, with hospital-acquired infections being one important complication. This post hoc, observational study aimed to analyze the impact of surgical and metabolic stress as defined by the surrogate marker hemoglobin A1c (HbA1c), in relation to self-reported DM2, on perioperative infection rates in a subcohort of the Surgical Site Infection (SSI) Trial population.

Methods

All patients of the SSI study were screened for HbA1c levels measured perioperatively for elective or emergency surgery and classified according to the American Diabetes Association HbA1c cutoff values. SSI and nosocomial infections, self-reported state of DM2 and type of surgery (minor, major) were assessed.

Results

HbA1c levels were measured in 139 of 5175 patients (2.7%) of the complete SSI study group. Seventy patients (50.4%) self-reported DM2, while 69 (49.6%) self-reported to be non-diabetic. HbA1c levels indicating pre-diabetes were found in 48 patients (34.5%) and diabetic state in 64 patients (46%). Forty-five patients of the group self-reporting no diabetes (65.2%) were previously unaware of their metabolic derangement (35 pre-diabetic and 10 diabetic). Eighteen infections were detected. Most infections (17 of 18 events) were found in patients with HbA1c levels indicating pre-/diabetic state. The odds for an infection was 3.9-fold (95% CI 1.4 to 11.3) higher for patients undergoing major compared to minor interventions. The highest percentage of infections (38.5%) was found in the group of patients with an undiagnosed pre-/diabetic state undergoing major surgery.

Conclusions

These results encourage investment in further studies evaluating a more generous and specific use of HbA1c screening in patients without self-reported diabetes undergoing major surgery.

Trial registration Clinicaltrials.gov identifier: NCT 01790529

Clinical practice guideline: evidence, recommendations and algorithm for the preoperative optimization of anemia, hyperglycemia and smoking

Preoperative optimization has not been explored comprehensively in the surgical literature, as this responsibility has often been divided among surgery, anesthesia and medicine. We developed an evidence-based clinical practice guideline to summarize existing evidence and present diagnostic and treatment algorithms for use by surgeons caring for patients scheduled to undergo major elective surgery. We focus on 3 common comorbid conditions seen across surgical specialties - anemia, hyperglycemia and smoking - as these conditions increase complication rates in patients undergoing major surgery and can be optimized successfully as soon as 6-8 weeks before surgery. With the ability to address these conditions earlier in the patient journey, surgeons can positively affect patient outcomes. The aim of this guideline is to bring optimization in the preoperative period under the existing umbrella of evidence-based surgical care.

Psychological resilience predicting cardiometabolic conditions in adulthood in the Midlife in the United States Study

Early adversity is associated with poor cardiometabolic health, potentially via psychological distress. However, not everyone exposed to adversity develops significant distress. Psychological resilience and positive psychological health despite adversity may protect against unfavorable cardiometabolic outcomes that are otherwise more likely. We examined early adversity, psychological resilience, and cardiometabolic risk among 3,254 adults in the Midlife in the United States Study. Psychological resilience was defined according to both early psychosocial adversity and adult psychological health (characterized by low distress and high wellbeing) at Wave 1 (1994 to 1995). Categorical resilience was derived by cross-classifying adversity (exposed versus unexposed) and psychological health (higher versus lower). We also assessed count of adversities experienced and psychological symptoms as separate variables. Incident cardiometabolic conditions (e.g., heart attack, stroke, and diabetes) were self-reported at Waves 2 (2004 to 2005) and 3 (2013 to 2014). Secondary analyses examined biological cardiometabolic risk using a composite of biomarkers available within a Wave-2 subsample. Logistic and Poisson regressions evaluated associations of resilience with cardiometabolic health across 20 follow-up y, adjusting for relevant covariates. In this initially healthy sample, nonresilient (adversity-exposed, lower psychological health) versus resilient (adversity-exposed, high psychological health) individuals had 43% higher odds of cardiometabolic conditions (95% CI 1.10 to 1.85). Odds of cardiometabolic conditions were similar among resilient versus unexposed, psychologically healthy individuals. More adversity experiences were associated with increased odds, while better psychological health with decreased odds of cardiometabolic conditions, and effects were largely independent. Patterns were similar for objectively assessed cardiometabolic risk. Psychological resilience in midlife may protect against negative cardiometabolic impacts of early adversity.

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.

Outcomes following coronary artery bypass surgery in diabetic treatment sub-groups. A propensity matched analysis of >7000 patients over 18 years

BACKGROUND

European System for Cardiac Operative Risk Evaluation II incorporates insulin-controlled diabetes whilst omitting tablet-controlled diabetes. Differences in adverse clinical outcomes following coronary artery bypass graft between these groups are poorly established. Therefore, a propensity matched comparison of short and longer term mortality and morbidity in insulin-controlled diabetes, tablet-controlled diabetes and non-diabetic patients was undertaken.

METHODS

Isolated first-time coronary artery bypass graft surgeries between April 1999 and April 2017 were propensity score matched by pre- and intra-operative variables.

RESULTS

8241 patients; 23.5% diabetics and 76.5% non-diabetics. The groups' demographical and clinical characteristics were comparable after matching. Insulin-controlled diabetes patients had significantly higher in-hospital mortality (3.8% vs. 1.7%, p < 0.05), multisystem failure (2.6% vs. 1.8%, p < 0.05), sternal wound infections requiring debridement (3.6% vs. 1.3%, p < 0.05), respiratory complications (25.6% vs. 21.9%, p < 0.05), new dialysis (4.7% vs. 0.9%, p < 0.05) and longer hospital stays (13.5 ± 13.3 vs. 10.6 ± 8.0, p < 0.05) compared to non-diabetic patients.Tablet-controlled diabetes patients had significantly higher strokes (2.9% vs. 1.2, p < 0.05), superficial sternal wound infections (6.7% vs. 5.4%, p < 0.05), respiratory complications (25.7% vs. 22.7%, p < 0.05), new dialysis (1.7% vs. 0.6%, p < 0.05), post-operative atrial fibrillation (37.1% vs. 33.9%, p < 0.05) and readmission with myocardial infarction (22.4% vs. 19.6%, p < 0.05) compared to non-diabetic patients.

CONCLUSION

Diabetic treatment sub-groups are an independent risk factor for sternal wound infection, new dialysis requirement, multisystem failure and readmission with myocardial infarction after isolated first coronary artery bypass graft surgery. The findings suggest the need for better risk stratification of diabetic groups prior to cardiac surgery and for improved cardiovascular risk management post-surgery in tablet-controlled diabetes patients.

Patterns of changes in fasting plasma glucose, hemoglobin A1c and the area under the curve during oral glucose tolerance tests in prediabetic subjects: results from a 16-year prospective cohort study among first-degree relatives of type 2 diabetic patients

AIM

This study aimed to identify the patterns of changes in glycemic indices over time in prediabetics and to classify these subjects as either having a high or low risk for developing diabetes in future.

METHODS

This prospective 16-year cohort study was conducted among 1228 prediabetic subjects. Three measurements including first visit, mean values during the follow-up period, and last visit from fasting plasma glucose (FPG), glycosylated hemoglobin (HbA1C), and area under the curve during an oral glucose tolerance test (OGTT AUC) were used to evaluate the patterns of changes by using the latent Markov model (LMM).

RESULTS

The mean (standard deviation) age of subjects was 44.0 (6.8) years, and 73.6% of them were female. The LMM identified 2 latent states of subjects in terms of changes in FPG, HbA1c, OGTT AUC, and the combination of these glycemic measures: a low tendency to progress diabetes and a high tendency to progress diabetes with the latent state sizes (87, 13%), (94, 6%), (57, 43%), and (84, 16%), respectively. The LMM showed that the probability of transitioning from a low tendency to a high tendency to progress diabetes was higher than the probability of transitioning in the opposite direction.

CONCLUSION

Based on a long-term evaluation of patterns of changes in glycemic indices, we classified prediabetic subjects into 2 groups (high or low risk to progress diabetes states in future). Also, the method used enabled us to estimate the transition probabilities from low- to high-risk states and vice versa. Our results reemphasized the values of all 3 glycemic measures in clinical settings for identifying prediabetic people with a high risk of progressing diabetes and the need for more effective prevention strategies, which should be conducted as urgently in prediabetic life as high-risk subjects.

Association of serum free thyroxine and glucose homeostasis: Korea National Health and Nutrition Examination Survey

BACKGROUND/AIMS

Thyroid hormones are involved in wide range of glucose metabolism functions. Overt thyroid dysfunctions are related to altered glucose homeostasis. However, it is not conclusive as to whether subtle changes in thyroid hormones within normal ranges can induce alterations in glucose homeostasis. The aim of this study was to evaluate the association between thyroid hormone and glucose homeostasis parameters in subjects without overt thyroid dysfunction based on nationwide population data.

METHODS

In the Sixth Korea National Health and Nutrition Examination Survey 2015 (n = 7,380), data were collected from subjects with insulin and thyroid function measurements who were older than 19-years-old. After the exclusion of 5,837 subjects, a total of 1,543 patients were included in the analysis. Subjects were categorized into the quartiles of the free thyroxine (FT4). Fasting glucose, insulin, homeostatic model assessment of insulin resistance and hemoglobin A1c (HbA1c) levels were considered to be glucose homeostasis parameters.

RESULTS

Subjects with the highest FT4 quartile showed significantly lower fasting insulin and HbA1c levels. A significant inverse correlation FT4 and HbA1c levels was observed (β = -0.261, p = 0.025). In the logistic regression analysis, the highest quartile of FT4 was demonstrated to lower the risk of HbA1c to a greater degree than the median by approximately 40%, after adjusting for confounders, compared to the lowest quartile (p = 0.028).

CONCLUSION

We demonstrated subjects with a lower FT4 quartile exhibited high risk of HbA1c levels above the median value in a representative Korean population. Subjects with the lowest FT4 quartile should be cautiously managed in terms of altered glucose homeostasis.

Hysterectomy Complications Relative to HbA1c Levels: Identifying a Threshold for Surgical Planning

STUDY OBJECTIVE

To evaluate whether diabetes diagnosis and level of diabetes control as reflected by higher preoperative glycosylated hemoglobin (HbA_1c) levels are associated with increased complication rates after hysterectomy and to identify a threshold of preoperative HbA_1c level past which we should consider delaying surgery owing to increased risk of complications.

DESIGN

Retrospective cohort study.

SETTING

Hospitals in the Michigan Surgical Quality Collaborative between June 4, 2012, and October 17, 2017.

PATIENTS

Women with and without a diabetes diagnosis.

INTERVENTIONS

Hysterectomy.

MEASUREMENTS AND MAIN RESULTS

Data on demographics, preoperative HbA_1c values, surgical approach, composite postoperative complications, readmissions, emergency department visits, and reoperations were abstracted. The risk of a postoperative complication when diabetes was stratified by preoperative HbA_1c level was evaluated in a sensitivity analysis, and independent associations were identified in a mixed, multivariate logistic regression model. We identified 41 286 hysterectomies performed at 70 hospitals to be included for analysis. The sensitivity analysis identified 4 groups of risk for postoperative complications: group 1: no diabetes diagnosis and no HbA_1c value; group 2: no diabetes diagnosis, with HbA_1c levels between 4% and 6.5%; group 3: diabetes diagnosis and no HbA_1c value or HbA_1c levels <9%; and group 4: diabetes diagnosis with HbA_1c levels ≥9%. In the adjusted model, there were significant 32% and 34% increased odds of postoperative complications for groups 2 and 3, respectively, compared with group 1. There were more than 2-fold increased odds of complications for women with diabetes and a preoperative HbA_1c level ≥9% (group 4) compared with the women in group 1. Diabetes diagnosis with preoperative HbA_1c levels ≥9% had increased odds of complications compared with diabetes diagnosis with preoperative HbA_1c levels <9%. Patients with well-controlled diabetes seemed to have increased odds of complications with laparoscopic surgery.

CONCLUSION

Diabetes diagnosis and measurement of preoperative HbA_1c levels provide risk stratification for postoperative complications after hysterectomy, with the highest observed effect among patients with diabetes with a preoperative HbA_1c level ≥9%.

Significant association between blood lead (Pb) level and haemoglobin A1c in non-diabetic population

Although many heavy metals are necessary for normal biological function, a subset of heavy metals have no role in human physiology, such as lead (Pb) and arsenic (As). Such elements have deleterious effects on physiology and be associated with the incidence of diabetes and related metabolic syndromes. Haemoglobin A1c (HbA1c) is not only a useful diagnostic and prognostic parameter in patients with diabetes, but it is also helpful in prediction of future diabetic risk in non-diabetic patients. However, no studies have evaluated the relationship between heavy metal concentration and HbA1c in non-diabetic patients. Therefore, the present study was designed to address this issue. We performed surveys for general populations living in southern Taiwan from June 2016 to September 2018. All participants received face-to-face interviews, laboratory tests, and measurements of weight and height, waist circumference, heart rate, and systolic and diastolic blood pressures. HbA1c was positively associated with Log blood Pb, after adjustments for age, body mass index, fasting blood glucose, total cholesterol, and triglyceride. Additionally, a Log 1 μg/dL increase in Pb was associated with a small (0.819 mmol/mol, 95% confidence interval = 0.072-1.566) increase in HbA1c (P =  0.032). No association with HbA1c was observed for urine nickel, chromium, manganese, As, copper, and cadmium in the multivariable analysis. In conclusion, after adjusting for important clinical parameters, Log blood Pb was positively associated with HbA1c in our non-diabetic population. This finding implies that high blood Pb might have the potential to predict future diabetic risk in non-diabetic populations. Further prospective studies are necessary to validate this issue.

HbA1c and clinical outcomes after endovascular treatment in patients with posterior circulation large vessel occlusion: a subgroup analysis of a nationwide registry (BASILAR)

BACKGROUND AND AIMS

Recently, several clinical trials have shown that increased glycated hemoglobin (HbA1c) level is correlated with poor clinical outcomes in ischemic stroke patients after thrombolysis and possibly after mechanical thrombectomy. However, the effect of HbA1c on posterior circulation large vessel occlusion (PCLVO) patients treated with endovascular thrombectomy (EVT) remains unclear. This multicenter study assessed the association between the HbA1c levels and clinical outcomes in patients with PCLVO after EVT.

METHODS

We studied 385 PCLVO ischemic stroke patients included in the EVT for acute basilar artery occlusion study (BASILAR). Patients were divided into a high HbA1c level group (HbA1c >6.5%) and a low HbA1c level group (HbA1c ⩽6.5%). The efficacy outcome was a 90-day favorable functional outcome (modified Rankin Scale 0-3). The safety outcomes included symptomatic intracerebral hemorrhage and mortality at 90 days after EVT.

RESULTS

The frequency of a favorable outcome in patients with an HbA1c ⩽6.5% was significantly higher than that in the HbA1c >6.5% group (41.2% versus 26.2%, p = 0.001). In multivariate analysis with adjusted confounders, high HbA1c levels and favorable outcomes were significantly negatively correlated. There was also a significant association between high HbA1c levels and mortality after 3 months. The negative effects of high HbA1c levels on functional status after 3 months were exacerbated in patients aged ⩾65 years.

CONCLUSION

Our multicenter study suggests that a higher serum HbA1c level (HbA1c >6.5%) is an independent predictor of a 90-day poor outcome and mortality in patients with PCLVO after EVT, particularly in those aged ⩾65 years.Clinical Trial Registry identifier: ChiCTR1800014759.

Perioperative Evaluation and Management of Endocrine Disorders

Evaluation of endocrine issues is a sometimes overlooked yet important component of the preoperative medical evaluation. Patients with diabetes, thyroid disease, and hypothalamic-pituitary-adrenal axis suppression are commonly encountered in the surgical setting and require unique consideration to optimize perioperative risk. For patients with diabetes, perioperative glycemic control has the strongest association with postsurgical outcomes. The preoperative evaluation should include recommendations for adjustment of insulin and noninsulin diabetic medications before surgery. Recommendations differ based on the type of diabetes, the type of insulin, and the patient's predisposition to hyperglycemia or hypoglycemia. Generally, patients with thyroid dysfunction can safely undergo operations unless they have untreated hyperthyroidism or severe hypothyroidism. Patients with known primary or secondary adrenal insufficiency require supplemental glucocorticoids to prevent adrenal crisis in the perioperative setting. Evidence supporting the use of high-dose supplemental corticosteroids for patients undergoing long-term glucocorticoid therapy is sparse. We discuss an approach to these patients based on the dose and duration of ongoing or recent corticosteroid therapy. As with other components of the preoperative medical evaluation, the primary objective is identification and assessment of the severity of endocrine issues before surgery so that the surgeons, anesthesiologists, and internal medicine professionals can optimize management accordingly.

A prospective observational prevalence study of elevated HbA1c among elective surgical patients

Type 2 Diabetes Mellitus (DM) is a chronic disease with high prevalence worldwide. Using glycated haemoglobin (HbA1c) as a surrogate for potential pre-DM and DM conditions, our primary objective was to determine the HbA1c epidemiology in non-cardiac elective surgical patients in Singapore. Our secondary aim was to identify risk factors associated with elevated HbA1c. We conducted a prospective, observational single-centre study in adult patients. HbA1c screening was performed. Patient demographics and comorbidities were recorded. Patients were divided into those with HbA1C ≤ 6.0% and HbA1C ≥ 6.1%. Regression analyses were performed to identify associated factors. Subgroup analysis was performed comparing patients with HbA1C ≥ 6.1% and HbA1C ≥ 8.0%. Of the 875 patients recruited, 182 (20.8%) had HbA1c ≥ 6.1%, of which 32 (3.7%) had HbA1c ≥ 8%. HbA1C ≥ 6.1% was associated with Indian ethnicity [1.07 (1.01-1.13), p = 0.023], BMI > 27.5 [1.07 (1.02-1.11), p = 0.002], higher preoperative random serum glucose [1.03 (1.02-1.04), p < 0.001], pre-existing diagnosis of DM [1.85 (1.75-1.96), p < 0.001] and prediabetes [1.44 (1.24-1.67), p < 0.001], and peripheral vascular disease [1.30 (1.10-1.54), p = 0.002]. HbA1c ≥ 8% had an additional association with age > 60 years [0.96 (0.93-0.99), p = 0.017]. The prevalence of elevated HbA1c is high among the surgical population. Targeted preoperative HbA1c screening for at-risk elective surgical patients reduces cost, allowing focused use of healthcare resources.

Social Support, Strain, and Glycemic Control: A Path Analysis

Social support and strain have been linked with many health outcomes. However, less is known about whether these psychosocial factors are associated with Type 2 diabetes risk. This study uses the Midlife in the United States (MIDUS) dataset to examine the relationship between social support and strain from friends, family members, and spouse/partners and blood hemoglobin A1c levels in married/cohabiting adults who have not been diagnosed with diabetes. In addition, health locus of control is examined as a possible mediator. The study's findings suggest that support from friends is negatively associated with HbA1c levels, indicating a relationship between better glycemic control and social support from friends, and an indirect association for spouse/partner support. A direct effect for internal health locus of control was also found.

Diabetes in day case general and vascular surgery: A multicentre regional audit

BACKGROUND

People with Diabetes Mellitus (DM) are at increased risk of postoperative complications if their HbA1C readings are not well controlled. In the UK, there are clear national guidelines requiring all people with DM to have HbA1C blood testing within 6months before undergoing surgery and that these readings should be below 69 mmol/mol if this is safe to achieve. The aim of this study was to determine whether hospitals in the region were compliant with the guidelines.

METHODS

Data were prospectively collected from seven hospitals across the East of England region from 1st October 2017 to 31st March 2018 (6 months) in all people with DM undergoing elective day case procedures in General and Vascular surgery for benign disease.

RESULTS

A total of 181 people with DM were included in the study, of whom 77.9% were male patients and the median age was 63 years. The three most commonly performed operations were laparoscopic cholecystectomy (20.9%, n = 38/181), inguinal hernia repair (20.4%, n = 37/181) and umbilical/para-umbilical hernia repair (11.0%, n = 20/181). In keeping with the national guidelines, only 86.7% (n = 157/181) of patients had an HbA1C tested within 6 months prior to their surgery date. Of the patients who had a preoperative HbA1C, 14 (n = 14/157, 8.9%) had an HbA1C ≥ 69 mmol/mol, and 12 (n = 12/14, 85.7%) of these proceeded to surgery without optimisation of their HbA1C.

CONCLUSION

A significant proportion of people with diabetes undergoing elective day case procedures in our region do not have HbA1C testing within 6 months of their procedure as recommended by the national guidelines. In patients who do have a high HbA1C, the majority still undergo surgery without adequate control of their DM. Greater awareness amongst healthcare workers and robust pathways are required for this vulnerable group of patients if we are to reduce the risk of developing postoperative complication rates.

The association of preoperative haemoglobin A1c with 30-day postoperative surgical site infection following non-cardiac surgery

Diabetes has been shown to be associated with postoperative infections; however, the association of haemoglobin A1c (HbA1c) with postoperative surgical site infections (SSI) is unclear. All HbA1c data from patients receiving general, vascular, or orthopaedic surgeries between 1 January 2014 and 1 December 2016 were identified from hospital records. The primary outcome was 30-day SSI. Multivariable logistic regression was performed to determine if HbA1c was associated with infection. The cohorts assessed were: (1) HbA1c < 6.5% (reference group); (2) greater than or equal to 6.5% and less than 8.0%; (3) greater than or equal to 8.0% and less than 10.0%; and (4) greater than or equal to 10.0%. There were 3064 patients included in the final analysis. The overall rate of 30-day SSI was 2.42%. After adjusting for confounders, when compared to the reference group, HbA1c ≥ 8.0% and less than 10.0% (OR 2.4, 95% CI 1.2-4.7, p = 0.015) and HbA1c ≥ 10.0% (OR 3.0, 95% CI 1.2-7.3, p = 0.016) had increased odds ratio for 30-day SSI. A HbA1c of 8.0% or higher significantly increased the odds ratio of developing postoperative SSI (p < 0.05). This may aid in the development of guidelines for optimising diabetic patients.

Achieving a Preoperative Target HbA1c of < 69 mmol/mol in Elective Vascular and Orthopedic Surgery: A Retrospective Single Center Observational Study

INTRODUCTION

Diabetes mellitus (DM) is present in 10-15% of the surgical population. It is a known risk factor for adverse postoperative outcomes. UK perioperative guidance recommends optimizing glycemic control preoperatively, aiming for a target glycated hemoglobin (HbA_1c) of < 69 mmol/mol. However, real-world compliance with this guidance remains unknown. The aim of our study was to determine how many patients with DM undergoing elective orthopedic and vascular surgery had a preoperative HbA_1c of < 69 mmol/mol. We also reviewed the surgical reasons for non-concordance with the recommended preoperative HbA_1c target.

METHODS

This was a retrospective observational study of 1000 consecutive patients who had been referred for elective vascular and orthopedic surgery at a large tertiary center. Data were collected on these patients, both those with and without DM, between January 2016 and February 2017. Electronic databases were used to collect information on the patients' preoperative HbA_1c concentration and to determine whether there was a resulting delay in surgery when the preoperative HbA_1c target of < 69 mmol/mol was exceeded.

RESULTS

Of the 1000 patients referred for surgery (500 orthopedic and 500 vascular patients) included in the study, 201 (20%) had diabetes. Among these 201 people with DM, 155 (77%) had a preoperative HbA_1c < 69 mmol/mol. Among the 46 people with DM whose HbA_1c exceeded the recommended target, 41 were operated on despite the high HbA_1c level, and only five had their surgery deferred or canceled due to suboptimal preoperative glycemic control.

CONCLUSIONS

Our data shows that the majority (77% ) of people undergoing elective vascular and orthopedic surgery were able to achieve a target HbA_1c of < 69 mmol/mol. The current preoperative guidance is therefore achievable in a real-life setting. However, as is stated in the national guidance, this target should only be used where it is safe to do so and a degree of clinical discretion is necessary.

Trauma in the Diabetic Limb

Poorly controlled diabetes with comorbid manifestations negatively affects outcomes in lower extremity trauma, increasing the risk of short-term and long-term complications. Management strategies of patients with diabetes that experience lower extremity trauma should also include perioperative management of hyperglycemia to reduce adverse and serious adverse events.

HbA1c predicts long-term postoperative mortality in patients with unknown glycemic status at admission for vascular surgery: An exploratory study

BACKGROUND

Peripheral arterial disease (PAD) and diabetes mellitus (DM) represent major public health challenges and are tightly associated. To facilitate early diagnosis, HbA1c has been implemented as the preferred diagnostic tool for the diagnosis of type 2 DM. In this study, we compared and evaluated HbA1c, fasting plasma glucose (FPG), and 2-hour post-load glucose values to determine which test best predicted mortality in patients with PAD.

METHODS

In all, 273 PAD patients with unknown glycemic status admitted to Haukeland University Hospital for elective surgery between October 2006 and September 2007 were included in the study. All 273 patients underwent a standard oral glucose tolerance test (OGTT) in addition to determination of HbA1c; patients were then grouped into those with DM, intermediate hyperglycemia, and normoglycemia according to World Health Organization and International Expert Committee criteria.

RESULTS

All-cause mortality was 40% over a 9-year follow-up period. After adjusting for age, sex, and relevant medication, HbA1c was a predictor for mortality (hazard ratio [HR] 1.54; 95% confidence interval [CI] 1.03-2.32]; P = 0.04). The association did not achieve statistical significance in a fully adjusted Cox regression model, although the effect estimation of HbA1c on all-cause mortality remained largely unchanged (HR 1.39; 95% CI 0.92-2.09; P = 0.13). The OGTT was not a predictor of long-term mortality.

CONCLUSIONS

The results indicate that HbA1c is a useful marker in the preoperative screening of patients of unknown glycemic status at the time of admission for vascular surgery, and may identify people at high risk of long-term mortality following surgical treatment for PAD.

Preoperative hemoglobin A1c levels and increased risk of adverse limb events in diabetic patients undergoing infrainguinal lower extremity bypass surgery in the Vascular Quality Initiative

BACKGROUND

The impact of preoperative glycemic control on the risk of adverse perioperative outcomes in diabetic patients undergoing lower extremity bypass (LEB) surgery is not well-understood. We determined whether higher preoperative hemoglobin A1c (HbA1c) levels are associated with an increased risk of major adverse limb events, major adverse cardiovascular events, and mortality in diabetic patients undergoing infrainguinal LEB.

METHODS

A retrospective review of all infrainguinal LEB surgeries in the Vascular Quality Initiative registry from January 2012 to February 2017 was performed. Only surgeries performed on diabetic patients with complete demographic and clinical data, including HbA1c value at the time of LEB, were included for analysis (n = 7727). Entries were stratified according to the following HbA1c levels: 6 or less (n = 1087), greater than 6 to 7 or less (n = 2137), greater than 7 to 8 or less (n = 1657), and greater than 8 (n = 2846). Multivariate logistic regression was used to determine the association of preoperative HbA1c levels on the risk of in-hospital major adverse limb events (above ankle amputation, loss of primary graft patency), major adverse cardiovascular events (myocardial infarction, stroke, congestive heart failure, cardiac arrhythmia), and mortality.

RESULTS

The number of surgeries complicated by adverse limb and cardiovascular events were 356 (4.6%) and 1314 (17.0%), respectively. There were 72 in-hospital deaths (0.9%). After adjustment for clinical and demographic variables, patients with high HbA1c values (≥8%) were at an increased risk of adverse limb events (odds ratio [OR], 1.37; 95% confidence interval [CI], 1.01-1.86) compared with those with a normal HbA1c (>6% to ≤7%). High HbA1c values were not associated with an increased risk of cardiovascular events (OR, 1.07; 95% CI, 0.81-1.43) or mortality (OR, 1.57; 95% CI, 0.83-3.03). Patients with low HbA1c values (≤6%) did not experience a significantly higher risk for any of the three outcomes. In a stratified analysis, the association of high HbA1c values with adverse limb events was only present in those presenting without critical limb ischemia (OR 1.82; 95% CI, 1.05-3.16).

CONCLUSIONS

Poor preoperative glycemic control in diabetic individuals undergoing infrainguinal LEB, particularly in those without critical limb ischemia, is associated with an increased risk of in-hospital limb events. Further study should evaluate whether improved efforts to identify individuals with poorly controlled diabetes and subsequent interventions to better optimize glycemic control during the preoperative period improve limb outcomes after LEB.

Pre-operative optimisation of the surgical patient with diagnosed and undiagnosed diabetes: a practical review

Peri-operative hyperglycaemia, whether the cause is known diabetes, undiagnosed diabetes or stress hyperglycaemia, is a risk factor for harm, increased length of stay and death. There is increasing evidence that peri-operative hyperglycaemia is a modifiable risk factor, and many of the interventions required to improve the outcome of surgery must be instituted before the actual surgical admission. These interventions depend on communication and collaboration within the multidisciplinary team along each stage of the patient journey to ensure that integration of care occurs across the whole of the patient-centred care pathway.

Perioperative Management of Diabetes Mellitus: Novel Approaches

PURPOSE OF REVIEW

Several studies have demonstrated the benefits of glycemic control in the perioperative period and there is ongoing interest in development of systematic approaches to achieving glycemic control. This review discusses currently available data and proposes a new approach to the management of hyperglycemia in the perioperative period.

RECENT FINDINGS

In a recent study, we demonstrated that early preoperative identification of patients with poorly controlled diabetes and proactive treatment through various phases of surgery improves glycemic control, lowers the risk of surgical complications, and decreases the length of hospital stay. Implementation of a perioperative diabetes program that systematically identifies and treats patients with poor glycemic control early in the preoperative period is feasible and improves clinical care of patients undergoing elective surgery.

Influence of Type 2 Diabetes Mellitus and Preoperative Hemoglobin A1c Levels on Outcomes of Liver Transplantation

Liver transplant centers often establish hemoglobin A1c (HbA1C) criteria for candidates with type 2 diabetes mellitus (T2DM) based on data from other surgical specialties showing worse outcomes in patients with poor glycemic control. However, because of the reduced reliability of HbA1C in cirrhosis, it is unclear whether pretransplant HbA1C values are predictive of postoperative complications in liver recipients. We retrospectively examined the association between preoperative HbA1C and postoperative outcomes in 173 consecutive patients who underwent liver transplantation at the University of Cincinnati Medical Center between August 2012 and March 2015. Demographic correlates of pretransplant HbA1C included age, T2DM, native Model for End‐Stage Liver Disease, hemoglobin, serum albumin, and nonalcoholic steatohepatitis as the indication for transplantation. No association was identified between pretransplant HbA1C and most outcome measures, including survival, length of stay, reoperation or readmission rates, rejection, bacteremia, and viremia. Significant correlates of HbA1C in liver recipients with diabetes were posttransplant insulin requirement and anastomotic biliary stricture formation. On multivariate analysis, HbA1C was the sole determinant of biliary strictures, with patients in the highest quartile (HbA1C >7.3%) exhibiting a 4‐fold increased risk. Correlation of HbA1C with morning blood glucose levels was much tighter after versus before transplantation. Conclusion: Preoperative HbA1C is predictive of anastomotic biliary stricture formation and the need for insulin following liver transplantation.

Preoperative Laboratory Testing

Obtaining routine preoperative laboratory tests increases health care costs and has been listed, by the Choosing Wisely Campaign, as one of the top 5 practices anesthesiologists should avoid. Routine testing without clinical indication is not cost-effective and could cause harm and unnecessary delays. Abnormal findings are more likely to be false positive and costly to pursue, introduce new risks, and increase anxiety for the patient. Preoperative testing need to be performed only following a targeted history and physical examination, factoring severity of surgery, and comorbidities such that the benefit of the test outweighs risk.

Perioperative insulin therapy

Surgical patients commonly develop hyperglycemia secondary to the neuroendocrine stress response. Insulin treatment of hyperglycemia is required to overcome the perioperative catabolic state and acute insulin resistance. Besides its metabolic actions on glucose metabolism, insulin also displays nonmetabolic physiological effects. Preoperative glycemic assessment, maintenance of normoglycemia, and avoidance of glucose variability are paramount to optimize surgical outcomes. This review discusses the basic physiology and effects of insulin as well as practical issues pertaining to its management during the perioperative period.

Association of Elevated Pre-operative Hemoglobin A1c and Post-operative Complications in Non-diabetic Patients: A Systematic Review

IMPORTANCE

Pre-operative hyperglycemia is associated with post-operative adverse outcomes in diabetic and non-diabetic patients. Current pre-operative screening includes random plasma glucose, yet plasma glycated hemoglobin (HbA1c) is a better measure of long-term glycemic control. It is not clear whether pre-operative HbA1c can identify non-diabetic patients at risk of post-operative complications.

OBJECTIVE

The systematic review summarizes the evidence pertaining to the association of suboptimal pre-operative HbA1c on post-operative outcomes in adult surgical patients with no history of diabetes mellitus.

EVIDENCE REVIEW

A detailed search strategy was developed by a librarian to identify all the relevant studies to date from the major online databases.

FINDINGS

Six observational studies met all the eligibility criteria and were included in the review. Four studies reported a significant association between pre-operative HbA1c levels and post-operative complications in non-diabetic patients. Two studies reported increased post-operative infection rates, and two reported no difference. Of four studies assessing the length of stay, three did not observe any association with HbA1c level and only one study observed a significant impact. Only one study found higher mortality rates in patients with suboptimal HbA1c.

CONCLUSIONS AND RELEVANCE

Based on the limited available evidence, suboptimal pre-operative HbA1c levels in patients with no prior history of diabetes predict post-operative complications and represent a potentially modifiable risk factor.

Effect of A1C and Glucose on Postoperative Mortality in Noncardiac and Cardiac Surgeries

OBJECTIVE

Hemoglobin A_1c (A1C) is used in assessment of patients for elective surgeries because hyperglycemia increases risk of adverse events. However, the interplay of A1C, glucose, and surgical outcomes remains unclarified, with often only two of these three factors considered simultaneously. We assessed the association of preoperative A1C with perioperative glucose control and their relationship with 30-day mortality.

RESEARCH DESIGN AND METHODS

Retrospective analysis on 431,480 surgeries within the Duke University Health System determined the association of preoperative A1C with perioperative glucose (averaged over the first 3 postoperative days) and 30-day mortality among 6,684 noncardiac and 6,393 cardiac surgeries with A1C and glucose measurements. A generalized additive model was used, enabling nonlinear relationships.

RESULTS

A1C and glucose were strongly associated. Glucose and mortality were positively associated for noncardiac cases: 1.0% mortality at mean glucose of 100 mg/dL and 1.6% at mean glucose of 200 mg/dL. For cardiac procedures, there was a striking U-shaped relationship between glucose and mortality, ranging from 4.5% at 100 mg/dL to a nadir of 1.5% at 140 mg/dL and rising again to 6.9% at 200 mg/dL. A1C and 30-day mortality were not associated when controlling for glucose in noncardiac or cardiac procedures.

CONCLUSIONS

Although A1C is positively associated with perioperative glucose, it is not associated with increased 30-day mortality after controlling for glucose. Perioperative glucose predicts 30-day mortality, linearly in noncardiac and nonlinearly in cardiac procedures. This confirms that perioperative glucose control is related to surgical outcomes but that A1C, reflecting antecedent glycemia, is a less useful predictor.

Perioperative management of adult diabetic patients. Preoperative period

In diabetic patients undergoing surgery, we recommend assessing glycaemic control preoperatively by assessing glycated haemoglobin (HbA1c) levels and recent capillary blood sugar (glucose) levels, and to adjust any treatments accordingly before surgery, paying particular attention to specific complications of diabetes. Gastroparesis creates a risk of stasis and aspiration of gastric content at induction of anaesthesia requiring the use of a rapid sequence induction technique. Cardiac involvement can be divided into several types. Coronary disease is characterised by silent myocardial ischaemia, present in 30-50% of T2D patients. Diabetic cardiomyopathy is a real cause of heart failure. Finally, cardiac autonomic neuropathy (CAN), although rarely symptomatic, should be investigated because it causes an increased risk of cardiovascular events and a risk of sudden death. Several signs are suggestive of CAN, and confirmation calls for close perioperative surveillance. Chronic diabetic kidney disease (diabetic nephropathy) aggravates the risk of perioperative acute renal failure, and we recommend measurement of the glomerular filtration rate preoperatively. The final step of the consultation concerns the management of antidiabetic therapy. Preoperative glucose infusion is not necessary if the patient is not receiving insulin. Non-insulin drugs are not administered on the morning of the intervention except for metformin, which is not administered from the evening before. The insulins are injected at the usual dose the evening before. The insulin pump is maintained until the patient arrives in the surgical unit. It should be remembered that insulin deficiency in a T1D patient leads to ketoacidosis within a few hours.

The impact of glycaemic variability on the surgical patient

PURPOSE OF REVIEW

Diabetes is the most prevalent long-term metabolic condition and its incidence continues to increase unabated. Patients with diabetes are overrepresented in the surgical population. It has been well recognized that poor perioperative diabetes control is associated with poor surgical outcomes. The outcomes are worst for those people who were not recognized as having hyperglycaemia.

RECENT FINDINGS

Recent work has shown that preoperative recognition of diabetes and good communication between the clinical teams at all stages of the patient pathway help to minimize the potential for errors, and improve glycaemic control. The stages of the patient journey start in primary care and end when the patient goes home. The early involvement of the diabetes specialist team is important if the glycated haemoglobin is more than 8.5%, and advice sought if the preoperative assessment team is not familiar with the drug regimens. To date the glycaemic targets for the perioperative period have remained uncertain, but recently a consensus is being reached to ensure glucose levels remain between 108 and180 mg/dl (6.0 and 10.0 mmol/l). There have been a number of ways to achieve these - primarily by manipulating the patients' usual diabetes medications, to also allow day of surgery admission.

SUMMARY

glycaemic control remains an important consideration in the surgical patient.

Retinal vascular imaging technology to monitor disease severity and complications in type 1 diabetes mellitus: A systematic review

OBJECTIVE

Type 1 diabetes mellitus (T1DM) is a major disease affecting a large number of young patients. In the recent years, retinal vascular imaging has provided an objective assessment of vascular health in patients with T1DM. Our study aimed to review the current literature on retinal vascular parameters in young patients with T1DM in order to understand the following: (i) How retinal vessels are affected in T1DM (ii) How such vascular changes can be predictive of future diabetic microvascular complications METHODS: We performed a systematic review and extracted relevant data from 17 articles.

RESULTS

We found significant correlations between retinal vessel changes and diabetes-related risk factors (eg, hypertension, hyperlipidemia, and obesity), diabetes-related features (eg, diabetes duration and glycemic control), and diabetes-related microvascular complications (eg, diabetic retinopathy, nephropathy, and neuropathy).

CONCLUSION

Our findings suggest that retinal microvasculature is associated with both disease severity and complications in young patients with T1DM.

The effect of sevoflurane on the transmural dispersion of repolarisation in patients with type 2 diabetes mellitus: a prospective observational study

The 'torsadogenic' property of a drug is linked to its ability to increase the transmural dispersion of repolarisation, represented by the interval between the peak of, and the end of, the T-wave (Tp-e interval) in an electrocardiogram. Reports have consistently shown that sevoflurane does not increase the Tp-e interval. Type 2 diabetes is a risk factor for increased QTc (rate-corrected QT interval), QTcd (rate-corrected QTc dispersion: difference between the maximum and the minimum QTc interval), and Tp-e, as well as the rate-corrected Tp-e (Tp-e/QTc ratio). The study aimed to ascertain whether sevoflurane increased the Tp-e interval and Tp-e/QTc ratio in patients with diabetes, thereby increasing their risk of torsades. We enrolled 35 female patients; 17 with type 2 diabetes and 18 controls undergoing non-laparoscopic surgery under sevoflurane anaesthesia. The Tp-e interval, Tp-e/QTc ratio, QTc and QTcd were recorded after intubation, 5, 10, 30 and 60 minutes into the anaesthetic, and were compared between the groups. No significant increase in the Tp-e interval or Tp-e/QTc was observed between or within the groups (a 13 ms increase was considered significant). In the control group, the QTc was significantly increased from baseline immediately after intubation (449 versus 414 ms, <i>P</i> <0.001); at 5 minutes (434 versus 414 ms, <i>P</i>=0.01); at 10 minutes (444 versus 414 ms, <i>P</i>=0.002); at 30 minutes (439 versus 414 ms, <i>P</i>=0.001) and at 60 minutes (442 versus 414 ms; <i>P</i> <0.001) (a 20 ms increase was considered significant). No significant increase in QTc was observed in the diabetic group. There were no between or within group differences observed for QTcd. Our findings suggest that sevoflurane does not have a significant predictable pro-arrhythmic effect in type 2 diabetic patients in the absence of other factors affecting ventricular repolarisation.

[Evaluation and perioperative management of patients with diabetes mellitus. A challenge for the anesthesiologist]

Diabetes mellitus (DM) is characterized by alteration in carbohydrate metabolism, leading to hyperglycemia and increased perioperative morbidity and mortality. It evolves with diverse and progressive physiological changes, and the anesthetic management requires attention regarding this disease interference in multiple organ systems and their respective complications. Patient's history, physical examination, and complementary exams are important in the preoperative management, particularly glycosylated hemoglobin (HbA1c), which has a strong predictive value for complications associated with diabetes. The goal of surgical planning is to reduce the fasting time and maintain the patient's routine. Patients with Type 1 DM must receive insulin (even during the preoperative fast) to meet the basal physiological demands and avoid ketoacidosis. Whereas patients with Type 2 DM treated with multiple injectable and/or oral drugs are susceptible to develop a hyperglycemic hyperosmolar state (HHS). Therefore, the management of hypoglycemic agents and different types of insulin is fundamental, as well as determining the surgical schedule and, consequently, the number of lost meals for dose adjustment and drug suspension. Current evidence suggests the safe target to maintain glycemic control in surgical patients, but does not conclude whether it should be obtained with either moderate or severe glycemic control.