Impact of preoperative glycometabolic status on outcomes in cardiac surgery: Systematic review and meta-analysis

Use of an insulin titration protocol based on continuous glucose monitoring in postoperative cardiac surgery patients with type 2 diabetes and prediabetes: a randomized controlled trial

BACKGROUND

Maintaining optimal glucose control is critical for postoperative care cardiac surgery patients. Continuous glucose monitoring (CGM) in this setting remains understudied. We evaluated the efficacy of CGM with a specialized titration protocol in cardiac surgery patients with type 2 diabetes (T2D) and prediabetes.

METHODS

In this randomized-controlled trial, 54 cardiac surgery patients were randomized one day post-surgery, with 27 CGM and 25 point-of-care (POC) patients completing the study. The CGM group used Dexcom G6 with a CGM-specialized titration protocol, while the POC group used standard monitoring with blinded CGM. The primary outcome was time-in-range (TIR) 100-180 mg/dL for 7 days post-surgery. Secondary outcomes included various glycemic metrics and surgical outcomes. Multiple comparison adjustments were performed using false-discovery-rate (FDR).

RESULTS

Thirty-one (59.6%) had diabetes and 21 (40.4%) had prediabetes. While TIR 100-180 mg/dL showed no difference (74.7% vs. 71.6%, FDR-adjusted p = 0.376), the CGM group demonstrated improvements in TIR 70-180 mg/dL (83.8% vs. 75.8%, FDR-adjusted p = 0.026), time-in-tight-range (TITR) 100-140 mg/dL (46.3% vs. 36.3%, FDR-adjusted p = 0.018), and TITR 70-140 mg/dL (55.3% vs. 40.5%, FDR-adjusted p = 0.003). Both groups maintained very low rates of time below range (< 70 mg/dL: 0.03% vs. 0.18%, FDR-adjusted p = 0.109). The CGM group showed lower postoperative atrial fibrillation (AF) (18.8% vs. 55.6%, FDR-adjusted p = 0.04999).

CONCLUSION

While the primary outcome was not achieved, CGM with a specialized titration protocol demonstrated safe glycemic control with improvements in TIR 70-180 mg/dL and TITRs in cardiac surgery patients with T2D and prediabetes. The observed reduction in postoperative AF warrants further investigation.

TRIAL REGISTRATION

ClinicalTrials.gov NCT06275971.

Glycated Haemoglobin (HbA1C) in Cardiac Surgery: A Narrative Review

Background: Perioperative dysglycaemia in cardiac surgery is associated with poor outcomes. Glycaemic variability rather than glucose levels is a predictor of the length of an ICU stay, a rise in creatinine and acute kidney injury after cardiac surgery. Glycated haemoglobin (HbA1C) values correspond closely to average blood glucose levels and cut-off values can be used to define a diabetic and pre-diabetic status. These have been correlated with perioperative events. Methods: In this narrative review, MEDLINE (via PubMed) and the Cochrane Library were used to search for the effects of different preoperative HbA1C levels on the postoperative outcomes after cardiac surgery. HbA1C values correspond closely with average blood glucose levels and cut-off values can be used to define a diabetic and pre-diabetic status; these have been correlated with perioperative events. This narrative review discusses the role of HbA1C in cardiac surgery. Discussion: The scientific data show controversial results: some systematic reviews and randomised control trials demonstrated that a high level of HbA1C seems to be an indicator for postoperative complications in cardiac surgery; other studies dissented and reported that mortality and morbidity cannot be directly attributed to HbA1c levels. Conclusions: The scientific community seems to be in general agreement that high levels of HbA1C are prognostic markers of adverse outcomes post cardiac surgery, but it has also been proved that there could be multiple underlying factors contributing to them.

Anaerobic Glycolysis and Ischemic Stroke: From Mechanisms and Signaling Pathways to Natural Product Therapy

Ischemic stroke is a serious condition that results in high rates of illness and death. Anaerobic glycolysis becomes the primary means of providing energy to the brain during periods of low oxygen levels, such as in the aftermath of an ischemic stroke. This process is essential for maintaining vital brain functions and has significant implications for recovery following a stroke. Energy supply by anaerobic glycolysis and acidosis caused by lactic acid accumulation are important pathological processes after ischemic stroke. Numerous natural products regulate glucose and lactate, which in turn modulate anaerobic glycolysis. This article focuses on the relationship between anaerobic glycolysis and ischemic stroke, as well as the associated signaling pathways and natural products that play a therapeutic role. These natural products, which can regulate anaerobic glycolysis, will provide new avenues and perspectives for the treatment of ischemic stroke in the future.

Risk factors for sternal wound infection after median sternotomy: A nested case-control study and time-to-event analysis

Although potential risk factors for sternal wound infection (SWI) have been extensively studied, the onset time of SWI and different risk factors for superficial and deep SWI were rarely reported. This nested case-control study aims to compare the onset time and contributors between superficial and deep SWI. Consecutive adult patients who underwent cardiac surgery through median sternotomy in a single center from January 2011 to January 2021 constituted the cohort. The case group was those who developed SWI as defined by CDC and controls were matched 6:1 per case. Kaplan-Meier analysis, LASSO and univariate and multivariate Cox regressions were performed. A simple nomogram was established for clinical prediction of the risk of SWI. The incidence of SWI was 1.1% (61 out of 5471) in our cohort. Totally 366 controls were matched to 61 cases. 26.2% (16 of 61) SWI cases were deep SWI. The median onset time of SWI was 35 days. DSWI had a longer latency than SSWI (median time 46 days vs. 32 days, p = 0.032). Kaplan-Meier analyses showed different time-to-SWI between patients with and without DM (p = 0.0011) or MI (p = 0.0019). Multivariate Cox regression showed that BMI (HR = 1.083, 95% CI: 1.012-1.116, p = 0.022), DM (HR = 2.041, 95% CI: 1.094-3.805, p = 0.025) and MI (HR = 2.332, 95% CI: 1.193-4.557, p = 0.013) were independent risk factors for SWI. Superficial SWI was only associated with BMI (HR = 1.089, 95% CI: 1.01-1.175, p = 0.027), while deep SWI was associated with DM (HR = 3.271, 95% CI: 1.036-10.325, p = 0.043) and surgery time (HR = 1.004, 95% CI: 1.001-1.008, p = 0.027). The nomogram for SWI prediction had an AUC of 0.67, good fitness and clinical effectiveness as shown by the calibration curve and decision curve analyses. BMI, DM and MI were independent risk factors for SWI. DSWI had a longer latency and different risk factors compared to SSWI. The nomogram showed a fair performance and good effectiveness for the clinical prediction of SWI.

Glycosylated Hemoglobin (HbA1C) as a Predictor of Early Postoperative Outcomes After Coronary Artery Bypass Grafting: A Single-Center Observational Study

Background Diabetic patients present a majority of patients undergoing surgical revascularization. Hyperglycemia is associated with increased adverse events. Glycosylated hemoglobin (HbA1c) is an effective biological marker for long-term glycemic control. As a result, there is an increased trend in its use as a predictor of adverse outcomes. This study aims to assess the impact of elevated HbA1c on the occurrence of postoperative complications after coronary artery bypass grafting (CABG). Methods We conducted a retrospective review of medical records from January 2015 to December 2022 for adult patients who underwent isolated CABG. We assessed patient demographics, medication, laboratory results, HbA1c results, and clinical data. The separate statistical models were designed to assess the predictors for the development of postoperative complications.  Results This retrospective single-center study was conducted on 289 consecutive adult patients who underwent on-pump CABG. Patient demographics showed that uncontrolled HbA1c was more in females (p=0.022), and hemodialysis patients (p=0.018). Across different levels of HbA1C, there were no significant differences in terms of the incidence of postoperative complications (p=0.788 for infection, p=0.372 for the need for blood transfusion, p=0.721 for heart failure, p=0.692 for arrhythmia, and p=0.712 for death). HbA1c had no predictive value for postoperative complications as indicated by multivariate and stepwise analysis in a separate model for each complication with receiver operator characteristics curves of each model showing similar strength of both multivariate and stepwise models. Conclusions In our data, elevated preoperative HbA1c had no predictive value for early complications and intermediate postoperative outcomes. We recommend that surgery should proceed without delay, even if patients have elevated HbA1C levels. As for elective patients with low-risk features and anatomy, optimizing preoperative glycemic control can be considered.

Impact of systematic diabetes screening on peri-operative infections in patients undergoing cardiac surgery

Detection of high glycated hemoglobin (A1c) is associated with worse postoperative outcomes, including predisposition to develop systemic and local infectious events. Diabetes and infectious Outcomes in Cardiac Surgery (DOCS) study is a retrospective case-control study aimed to assess in DM and non-DM cardiac surgery patients if a new screening and management model, consisting of systematic A1c evaluation followed by a specialized DM consult, could reduce perioperative infections and 30-days mortality. Effective July 2021, all patients admitted to the cardiac surgery of IRCCS ISMETT were tested for A1c. According to the new protocol, glucose values of patients with A1c ≥ 6% or with known diabetes were monitored. The diabetes team was activated to manage therapy daily until discharge or provide indications for the diagnostic-therapeutic process. Propensity score was used to match 573 patients managed according to the new protocol (the Screen+ Group) to 573 patients admitted before July 2021 and subjected to the traditional management (Screen-). Perioperative prevalence of infections from any cause, including surgical wound infections (SWI), was significantly lower in the Screen+ as compared with the Screen- matched patients (66 [11%] vs. 103 [18%] p = 0.003). No significant difference was observed in 30-day mortality. A1c analysis identified undiagnosed DM in 12% of patients without known metabolic conditions. In a population of patients undergoing cardiac surgery, systematic A1c evaluation at admission followed by specialist DM management reduces perioperative infectious complications, including SWI. Furthermore, A1c screening for patients undergoing cardiac surgery unmasks unknown DM and enhances risk stratification.

Perioperative Glycemic Management in Cardiac Surgery: A Narrative Review

Diabetes and hyperglycemic events in cardiac surgical patients are associated with postoperative morbidity and mortality. The causes of dysglycemia, the abnormal fluctuations in blood glucose concentrations, in the perioperative period include surgical stress, surgical techniques, medications administered perioperatively, and patient factors. Both hyperglycemia and hypoglycemia lead to poor outcomes after cardiac surgery. While trying to control blood glucose concentration tightly for better postoperative outcomes, hypoglycemia is the main adverse event. Currently, there is no definite consensus on the optimum perioperative blood glucose concentration to be maintained in cardiac surgical patients. This review provides an overview of perioperative glucose homeostasis, the pathophysiology of dysglycemia, factors that affect glycemic control in cardiac surgery, and current practices for glycemic control in cardiac surgery.

Association of Alternative Markers of Carbohydrate Metabolism (Fructosamine and 1,5-Anhydroglucitol) with Perioperative Characteristics and In-Hospital Complications of Coronary Artery Bypass Grafting in Patients with Type 2 Diabetes Mellitus, Prediabetes, and Normoglycemia

Patients with type 2 diabetes make up 25 to 40% of those referred for coronary bypass surgery, and the impact of diabetes on the results of the operation is studied in various aspects. To assess the state of carbohydrate metabolism before any surgical interventions, including CABG, daily glycemic control, and the determination of glycated hemoglobin (HbA1c) is recommended. Glycated hemoglobin reflects the glucose concentration for the 3 months prior to the measurement, but alternative markers that reflect glycemic fluctuations over a shorter period of time may be useful in preoperative preparation. The aim of this study was to study the relationship between the concentration of alternative markers of carbohydrate metabolism (fructosamine and 1,5-anhydroglucitol) with patients' clinical characteristics and the rate of hospital complications after coronary artery bypass grafting (CABG).

METHOD

In the cohort of 383 patients, besides the routine examination, additional markers of carbohydrate metabolism were determined before and on days 7-8 after CABG: glycated hemoglobin (HbA1c), fructosamine, and 1,5-anhydroglucitol. We evaluated the dynamics of these parameters in groups of patients with diabetes mellitus, prediabetes, and normoglycemia, as well as the association of these parameters with clinical parameters. Additionally, we assessed the incidence of postoperative complications and factors associated with their development.

RESULTS

In all groups of patients (diabetes mellitus, prediabetes, normoglycemia), there was a significant decrease in the level of fructosamine on the 7th day after CABG compared with baseline (p1st-2nd point 0.030, 0.001, and 0.038 in groups 1, 2, and 3, respectively), whereas the level of 1,5-anhydroglucitol did not change significantly. The preoperative level of fructosamine was associated with the risk of surgery according to the EuroSCORE II scale (p = 0.002), as were the number of bypasses (p = 0.012), body mass index and overweightness (p < 0.001 in both cases), triglyceride (p < 0.001) and fibrinogen levels (p = 0.002), preoperative and postoperative glucose and HbA1c levels (p < 0.001 in all cases), left atrium size (p = 0.028), multiplicity of cardioplegia, cardiopulmonary bypass duration and aortic clamp time (p < 0.001 in all cases). The preoperative level of 1,5-anhydroglucitol showed an inverse correlation with fasting glucose and fructosamine levels before surgery (p < 0.001 in all cases), intima media thickness (p = 0.016), and a direct correlation with LV end-diastolic volume (p = 0.020). The combined endpoint (presence of significant perioperative complications + extended hospital stay after surgery >10 days) was identified in 291 patients. In binary logistic regression analysis patient age (p = 0.005) and fructosamine level (p = 0.022) were independently associated with the development of this composite endpoint (presence of significant perioperative complications + extended hospital stay after surgery >10 days).

CONCLUSIONS

This study demonstrated that in patients after CABG there was the significant decrease in the level of fructosamine compared with baseline, whereas the level of 1,5-anhydroglucitol did not change. Preoperative fructosamine levels were one of the independent predictors of the combined endpoint. The prognostic value of preoperative assessment of alternative markers of carbohydrate metabolism in cardiac surgery deserves further study.

[Position statement: surgery and diabetes mellitus (Update 2023)]

This position statement reflects the perspective of the Austrian Diabetes Association concerning the perioperative management of people with diabetes mellitus based on the available scientific evidence. The paper covers necessary preoperative examinations from an internal/diabetological point of view as well as the perioperative metabolic control by means of oral antihyperglycemic and/or insulin therapy.

Impact of diabetes mellitus on long-term clinical and graft outcomes after off-pump coronary artery bypass grafting with pure bilateral skeletonized internal thoracic artery grafts

BACKGROUND

The effect of diabetes mellitus (DM) on the long-term outcomes of coronary artery bypass graft (CABG) remained debatable and various strategies exist for CABG; hence, clarifying the effects of DM on CABG outcomes is difficult. The current study aimed to evaluate the effect of DM on clinical and graft-related outcomes after CABG with bilateral internal thoracic artery (BITA) grafts.

METHODS

From January 2001 to December 2017, 3395 patients who underwent off-pump CABG (OPCAB) with BITA grafts were enrolled. The study population was stratified according to preoperative DM. The primary endpoint was cardiac death and the secondary endpoints were myocardial infarction (MI), revascularization, graft failure, stroke, postoperative wound infection, and a composite endpoint of cardiac death, MI, and revascularization. Multiple sensitivity analyses, including Cox proportional hazard regression and propensity-score matching analyses, were performed to adjust baseline differences.

RESULTS

After CABG, the DM group showed similar rates of cardiac death, MI, or revascularization and lower rates of graft failure at 10 years (DM vs. non-DM, 19.0% vs. 24.3%, hazard ratio [HR] 0.711, 95% confidence interval [CI] 0.549-0.925; P = 0.009) compared to the non-DM group. These findings were consistent after multiple sensitivity analyses. In the subgroup analysis, the well-controlled DM group, which is defined as preoperative hemoglobin A1c (HbA1c) of < 7%, showed lower postoperative wound infection rates (well-controlled DM vs. poorly controlled DM, 3.7% vs. 7.3%, HR 0.411, 95% CI 0.225-0.751; P = 0.004) compared to the poorly controlled DM group, which was consistent after propensity-score matched analysis.

CONCLUSIONS

OPCAB with BITA grafts showed excellent and comparable long-term clinical outcomes in patients with and without DM. DM might have a protective effect on competition and graft failure of ITA. Strict preoperative hyperglycemia control with target HbA1c of < 7% might reduce postoperative wound infection and facilitate the use of BITA in CABG.

Construction and validation of a nomogram for predicting survival in elderly patients with cardiac surgery

Background

In recent years, the number of elderly patients undergoing cardiac surgery has rapidly increased and is associated with poor outcomes. However, there is still a lack of adequate models for predicting the risk of death after cardiac surgery in elderly patients. This study sought to identify independent risk factors for 1-year all-cause mortality in elderly patients after cardiac surgery and to develop a predictive model.

Methods

A total of 3,752 elderly patients with cardiac surgery were enrolled from the Medical Information Mart for Intensive Care III (MIMIC-III) dataset and randomly divided into training and validation sets. The primary outcome was the all-cause mortality at 1 year. The Least absolute shrinkage and selection operator (LASSO) regression was used to decrease data dimensionality and select features. Multivariate logistic regression was used to establish the prediction model. The concordance index (C-index), receiver operating characteristic curve (ROC), and decision curve analysis (DCA) were used to measure the predictive performance of the nomogram.

Results

Our results demonstrated that age, sex, Sequential Organ Failure Assessment (SOFA), respiratory rate (RR), creatinine, glucose, and RBC transfusion (red blood cell) were independent factors for elderly patient mortality after cardiac surgery. The C-index of the training and validation sets was 0.744 (95%CI: 0.707-0.781) and 0.751 (95%CI: 0.709-0.794), respectively. The area under the curve (AUC) and decision curve analysis (DCA) results substantiated that the nomogram yielded an excellent performance predicting the 1-year all-cause mortality after cardiac surgery.

Conclusions

We developed a novel nomogram model for predicting the 1-year all-cause mortality for elderly patients after cardiac surgery, which could be an effective and useful clinical tool for clinicians for tailored therapy and prognosis prediction.

American Association of Clinical Endocrinology Clinical Practice Guideline: Developing a Diabetes Mellitus Comprehensive Care Plan-2022 Update

OBJECTIVE

The objective of this clinical practice guideline is to provide updated and new evidence-based recommendations for the comprehensive care of persons with diabetes mellitus to clinicians, diabetes-care teams, other health care professionals and stakeholders, and individuals with diabetes and their caregivers.

METHODS

The American Association of Clinical Endocrinology selected a task force of medical experts and staff who updated and assessed clinical questions and recommendations from the prior 2015 version of this guideline and conducted literature searches for relevant scientific papers published from January 1, 2015, through May 15, 2022. Selected studies from results of literature searches composed the evidence base to update 2015 recommendations as well as to develop new recommendations based on review of clinical evidence, current practice, expertise, and consensus, according to established American Association of Clinical Endocrinology protocol for guideline development.

RESULTS

This guideline includes 170 updated and new evidence-based clinical practice recommendations for the comprehensive care of persons with diabetes. Recommendations are divided into four sections: (1) screening, diagnosis, glycemic targets, and glycemic monitoring; (2) comorbidities and complications, including obesity and management with lifestyle, nutrition, and bariatric surgery, hypertension, dyslipidemia, retinopathy, neuropathy, diabetic kidney disease, and cardiovascular disease; (3) management of prediabetes, type 2 diabetes with antihyperglycemic pharmacotherapy and glycemic targets, type 1 diabetes with insulin therapy, hypoglycemia, hospitalized persons, and women with diabetes in pregnancy; (4) education and new topics regarding diabetes and infertility, nutritional supplements, secondary diabetes, social determinants of health, and virtual care, as well as updated recommendations on cancer risk, nonpharmacologic components of pediatric care plans, depression, education and team approach, occupational risk, role of sleep medicine, and vaccinations in persons with diabetes.

CONCLUSIONS

This updated clinical practice guideline provides evidence-based recommendations to assist with person-centered, team-based clinical decision-making to improve the care of persons with diabetes mellitus.

Akutes Nierenversagen

Das akute Nierenversagen oder die akute Nierenschädigung ist eine ernsthafte Erkrankung. Es gibt nur vage Zahlenangaben zum Auftreten. Im vorliegenden Beitrag wird versucht, die diabetologisch relevanten Aspekte dieser Erkrankung darzustellen. Die möglichen Ursachen werden aufgezeigt. Menschen mit Diabetes mellitus haben überwiegend ein höheres Risiko für ein akutes Nierenversagen als nicht von dieser Stoffwechselerkrankung Betroffene. Dies wird für diagnostische sowie klinisch relevante Risikokonstellationen dargestellt. Sowohl diagnostisch als auch therapeutisch ist die interdisziplinäre Kooperation insbesondere mit dem Fachgebiet Nephrologie erforderlich. Therapeutisch relevante Aspekte werden angerissen, auch medikamentöse Maßnahmen.