Glucose Variability Based on Continuous Glucose Monitoring Assessment Is Associated with Postoperative Complications after Cardiovascular Surgery

The impact of glucagon-like peptide-1 receptor agonists in the patients undergoing anesthesia or sedation: systematic review and meta-analysis

BACKGROUND

Glucagon-like peptide-1 agonist receptors (GLP-1RAs), medications used for glycemic control and weight loss, are increasing worldwide. In the perioperative period, the major concern related to GLP-1RA is gastric emptying delay and risk of aspiration. This meta-analysis and systematic review compared the risks and benefits of using GLP-1 agonist receptors and control in surgical and nonsurgical procedures under anesthesia or sedation.

METHODS

We systematically searched MEDLINE, Embase, and Cochrane for randomized controlled trials and observational studies involving patients > 18 years undergoing elective surgeries or procedures. Outcomes of interest were pre-procedural gastrointestinal (GI) symptoms, residual gastric content assessed by endoscopy, pulmonary aspiration during anesthesia/sedation, perioperative glycemic control, postoperative inotropic support, nausea/vomiting (PONV), atrial fibrillation, and 30-day mortality rate. We used a random effects model, with odds ratio and mean difference computed for binary and continuous outcomes, respectively.

RESULTS

Fourteen randomized and observational studies with 2143 adult patients undergoing elective surgeries and procedures were included. GLP-1RA resulted in increased pre-procedural GI symptoms (OR 7.66; 95% CI 3.42, 17.17; p < 0.00001; I2 = 0%) and elevated residual gastric content (OR 6.08; 95% CI 2.86, 12.94; p < 0.00001; I2 = 0%). GLP-1RA resulted in lower glycemic levels (MD - 0.73; 95% CI - 1.13, - 0.33; p = 0.0003; I2 = 90%) and lower rate of rescue insulin administration (OR 0.39; 95% CI 0.23, 0.68 p = 0.0009; I2 = 35%). There was no significant difference in rate of perioperative hypoglycemia (OR 0.60; 95% CI 0.29, 1.24; p = 0.17; I2 = 0%), hyperglycemia (OR 0.89; 95% CI 0.59, 1.34; p = 0.58; I2 = 38%), need for postoperative inotropic support (OR 0.57; 95% CI 0.33, 1.01; p = 0.05; I2 = 0%), atrial fibrillation (OR 1.02; 95% CI 0.52, 2.01; p = 0.95; I2 = 16%), rate of PONV (OR 1.35; 95% CI 0.82, 2.21; p = 0.24; I2 = 0%), and 30-day mortality rate (OR 0.54; 95% CI 0.14, 2.05; p = 0.25; I2 = 0%).

CONCLUSION

Compared to control, pre-procedural GLP-1RA increased the rate of GI symptoms and the risk of elevated residual gastric content despite adherence to fasting guidelines. GLP-1RA improved glycemic control and decreased the rate of rescue insulin administration. There was no significant difference in the rates of perioperative hypo or hyperglycemia, postoperative inotropic support, PONV, atrial fibrillation, and 30-day mortality.

Continuous Glucose Monitoring System After Coronary Artery Bypass Graft Surgery: A Feasibility Study

BACKGROUND

Blood glucose level variability has been associated with increased risk of complication in the postoperative setting of cardiovascular surgery. Although interesting for optimization of blood glucose management in this context, continuous blood glucose (CBG) devices can have a limited reliability in this context, in particular because of the use of paracetamol. The aim of this study was to evaluate the reliability of Dexcom G6®, a recently developed continuous glucose monitoring device.

METHODS

We performed a prospective, observational, non-randomized, single-centre study comparing Dexcom G6® CBG level monitoring with the standard methods routinely used in this context. The standard blood glucose values were paired to the time corresponding values measured with Dexcom G6®. Agreement between the two methods and potential correlation in case of paracetamol use were calculated.

RESULTS

From May 2020 to August 2021, 36 out of 206 patients operated for isolated coronary artery bypass grafting were enrolled; 673 paired blood glucose level were analyzed. Global agreement (ρc) was 0.85 (95% C.I.: 0.84-0.86), intensive care unit agreement was 0.78 (95%C.I.: 0.74-0.82) and ward agreement was 0.91 (95%C.I.: 0.89-0.93). In the diabetic population, it was 0.87 (95%C.I.: 0.85-0.90). When paracetamol was used, the difference was 0.02 mmol/l (95%C.I.: 0.29-0.33).

CONCLUSIONS

Dexcom G6® provides good blood glucose level accuracy in the postoperative context of cardiac surgery compared to the standard methods of measurements. The results are particularly reliable in the ward where the need for repeated capillary glucose measurements implies patient discomfort and time-consuming manipulations for the nursing staff.

Postoperative Insulin Dose for Cardiac Artery Bypass Graft and Other Cardiac Surgeries in Patients with Type 2 Diabetes: A Retrospective Study

Purpose

Recommendations on perioperative glycemic control in cardiac surgery are based on coronary artery bypass graft surgery (CABG), though coronary artery disease and valvular disease are pathologically distinct. We aimed to compare the postoperative insulin requirement between CABG and other cardiac surgeries in type 2 diabetic patients and identify predictive factors for the maximum postoperative insulin dose.

Patients and Methods

We retrospectively included 60 Japanese patients with diabetes/glucose intolerance (HbA1c > 37 mmol/mol [5.6%]) who were hospitalized for cardiovascular surgery between April 2017 and March 2019. We categorized the subjects into the CABG and non-CABG groups, and performed subgroup analysis on patients who received postoperative insulin therapy.

Results

The CABG group required a significantly higher insulin dose on postoperative days 2, 5, 6, and 7, and a significantly higher maximum postoperative insulin dose (24.6 U vs 9.7 U, P < 0.001) than the non-CABG group. Multivariate linear regression analyses showed that the independent determinants of the maximum postoperative insulin dose were HbA1c and duration of diabetes in the non-CABG group, and HbA1c in the CABG group.

Conclusion

CABG had a higher postoperative insulin requirement than other cardiovascular surgeries; early aggressive insulin therapy is indicated, especially for patients with higher HbA1c levels/longer duration of diabetes.

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.

Continuous Glucose Monitoring Reveals Perioperative Hypoglycemia in Most Patients With Diabetes Undergoing Major Surgery: A Prospective Cohort Study

OBJECTIVE

To investigate the frequency and duration of hypo- and hyperglycemia, assessed by continuous glucose monitoring (CGM) during and after major surgery, in departments with implemented diabetes care protocols.

SUMMARY BACKGROUND DATA

Inadequate glycemic control in the perioperative period is associated with serious adverse events, but monitoring currently relies on point blood glucose measurements, which may underreport glucose excursions.

METHODS

Adult patients without (A) or with diabetes [non-insulin-treated type 2 (B), insulin-treated type 2 (C) or type 1 (D)] undergoing major surgery were monitored using CGM (Dexcom G6), with an electrochemical sensor in the interstitial fluid, during surgery and for up to 10 days postoperatively. Patients and health care staff were blinded to CGM values, and glucose management adhered to the standard diabetes care protocol. Thirty-day postoperative serious adverse events were recorded. The primary outcome was duration of hypoglycemia (glucose <70 mg/dL). Clinicaltrials.gov: NCT04473001.

RESULTS

Seventy patients were included, with a median observation time of 4.0 days. CGM was recorded in median 96% of the observation time. The median daily duration of hypoglycemia was 2.5 minutes without significant difference between the 4 groups (A-D). Hypoglycemic events lasting ≥15 minutes occurred in 43% of all patients and 70% of patients with type 1 diabetes. Patients with type 1 diabetes spent a median of 40% of the monitoring time in the normoglycemic range 70 to 180 mg/dL and 27% in the hyperglycemic range >250 mg/dL. Duration of preceding hypo- and hyperglycemia tended to be longer in patients with serious adverse events, compared with patients without events, but these were exploratory analyses.

CONCLUSIONS

Significant duration of both hypo- and hyperglycemia was detected in high proportions of patients, particularly in patients with diabetes, despite protocolized perioperative diabetes management.

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.

The impact of perioperative glucose variability on outcomes after hip fracture

Diabetes is considered an independent risk factor for hip fracture. In the present study, we evaluated whether perioperative glucose variability (GV) was a significant predictor of the outcomes of patients with diabetes after hip fracture.We analyzed the characteristics and outcomes of all patients with hip fractures admitted to our hospital between September 2008 and December 2012. Patients with diabetes were grouped into tertiles for GV, and multivariate survival analysis included age, sex, fracture type, mean fasting plasma glucose, and GV.Among the 1099 patients included in this study, 239 (21.7%) had diabetes. Patients with diabetes were more likely to develop infectious complications (5.4% vs 2.8%, P = .045), and experience mortality postoperatively (1 month: 5.5% vs 2.7%, P = .052; 12 months: 15.1% vs 8.7%, P = .006). The postoperative mortality rate was increased across the GV tertiles, and GV was an independent predictor of 1- and 12-month mortality after surgery.Patients with diabetes had poor prognoses after hip fracture. Perioperative GV is an independent predictor of mortality in patients with diabetes. Therefore, GV might be considered a valid additional parameter to consider in the management of these patients.

Glycemic Variability Within 1 Year Following Surgery for Stage II-III Colon Cancer

OBJECTIVE

To examine glycemic variability within 1 month and 1 year following surgery among adult patients, with and without Type 2 Diabetes (T2D), treated for stage II-III colon cancer.

METHOD

A retrospective analysis of electronic health record data was conducted. Glycemic variability (i.e., standard deviation [SD] and coefficient of variation [CV] of > 2 blood glucose measures) was assessed within 1 month and within 1 year following colon surgery. Chi-square (χ²), Fisher's exact, and Mann-Whitney U tests were used for the analyses.

RESULTS

Among the sample of 165 patients with stage II-III colon cancer, those with T2D had higher glycemic variability compared to patients without T2D (p < .001), with values within 1 month following surgery (SD = 44.69 mg/dL, CV = 27.4%) vs (SD = 20.55 mg/dL, CV = 17.53%); and within 1 year following surgery (SD = 45.04 mg/dL, CV = 29.04%) vs (SD = 21.36 mg/dL, CV = 18.6%). Associations were found between lower body mass index and higher glycemic variability (i.e., SD [r = -.413, p < .05] and CV [r = -.481, p < .01]) within 1 month following surgery in patients with T2D. Higher preoperative glucose was associated with higher glycemic variability (i.e., SD r = .448, p < .01) within 1 year in patients with T2D. Demographic and clinical characteristics were weakly associated with glycemic variability in patients without T2D.

CONCLUSIONS

Patients with stage II-III colon cancer with T2D experienced higher glycemic variability within 1 month and within 1 year following surgery compared to those without T2D. Associations between glycemic variability and demographic and clinical characteristics differed by T2D status. Further research in prospective studies is warranted.

Real-World Studies Support Use of Continuous Glucose Monitoring in Type 1 and Type 2 Diabetes Independently of Treatment Regimen

Numerous randomized controlled trials (RCTs) have demonstrated the glycemic benefits of continuous glucose monitoring (CGM) in management of type 1 diabetes (T1D) and type 2 diabetes. Although RCTs remain the gold standard clinical study design, findings from these trials do not necessarily reflect the effectiveness of CGM or reveal the feasibility and wider applications for use in broader real-life settings. This review evaluates recent real-world evidence (RWE) demonstrating the value of CGM to improve clinical outcomes, such as avoidance of severe hypoglycemic and hyperglycemic crises, and improved measures of psychological health and quality of life. Additionally, this review considers recent RWE for the role of CGM to enhance health care resource utilization, including prediction of T1D and applications in gestational diabetes, chronic kidney disease, and monitoring during surgery.

Intermittent Use of Continuous Glucose Monitoring: Expanding the Clinical Value of CGM

In addition to the continuous use, the intermittent use of continuous glucose monitoring (CGM) is an application of CGM, expanding the typical medical use cases. There are a variety of reasons and occasions that speak in favor of using CGM only for a limited time. To date, these circumstances have not been sufficiently discussed. In this article, we define discontinuous or intermittent CGM use, provide reasons for using it, and expand on the benefits and possibilities of using CGM on a temporary basis. We aim to draw attention to this important topic in the discussion of CGM use and give examples for a different method of CGM use. As well, we would like to foster the allocation of CGM to the right patient groups and indications, especially in cases of limited resources. From a global point of view, intermittent CGM use is more likely to occur than continuous use, primarily for economic reasons.

Optimizing indices of AF susceptibility and burden to evaluate AF severity, risk and outcomes

Atrial fibrillation (AF) has heterogeneous patterns of presentation concerning symptoms, duration of episodes, AF burden, and the tendency to progress towards the terminal step of permanent AF. AF is associated with a risk of stroke/thromboembolism traditionally considered dependent on patient-level risk factors rather than AF type, AF burden, or other characterizations. However, the time spent in AF appears related to an incremental risk of stroke, as suggested by the higher risk of stroke in patients with clinical AF vs. subclinical episodes and in patients with non-paroxysmal AF vs. paroxysmal AF. In patients with device-detected atrial tachyarrhythmias, AF burden is a dynamic process with potential transitions from a lower to a higher maximum daily arrhythmia burden, thus justifying monitoring its temporal evolution. In clinical terms, the appearance of the first episode of AF, the characterization of the arrhythmia in a specific AF type, the progression of AF, and the response to rhythm control therapies, as well as the clinical outcomes, are all conditioned by underlying heart disease, risk factors, and comorbidities. Improved understanding is needed on how to monitor and modulate the effect of factors that condition AF susceptibility and modulate AF-associated outcomes. The increasing use of wearables and apps in practice and clinical research may be useful to predict and quantify AF burden and assess AF susceptibility at the individual patient level. This may help us reveal why AF stops and starts again, or why AF episodes, or burden, cluster. Additionally, whether the distribution of burden is associated with variations in the propensity to thrombosis or other clinical adverse events. Combining the improved methods for data analysis, clinical and translational science could be the basis for the early identification of the subset of patients at risk of progressing to a longer duration/higher burden of AF and the associated adverse outcomes.

[Atrial Fibrillation After Coronary Artery Bypass Surgery: Risk Factors, Prevention and Treatment]

This review focuses on the issue of atrial fibrillation (AF) following coronary bypass surgery in patients with ischemic heart disease. Risk factors of this complication are discussed in detail. The authors addressed the effect of diabetes mellitus on development of postoperative AF. Data on current methods for prevention and treatment of AF are provided.

Pathological Role of Advanced Glycation End Products (AGEs) and their Receptor Axis in Atrial Fibrillation

Accumulating evidence has shown that the incidence of atrial fibrillation (AF) is higher in patients with diabetes, especially those with poor glycemic control or long disease duration. Nonenzymatic glycation of amino acids of proteins, lipids, and nucleic acids has progressed under normal aging process and/or diabetic condition, which could lead to the formation and accumulation of advanced glycation end products (AGEs). AGEs not only alter the tertiary structure and physiological function of macromolecules, but also evoke inflammatory and fibrotic reactions through the interaction of cell surface receptor for AGEs (RAGE), thereby being involved in aging-related disorders. In this paper, we briefly review the association of chronic hyperglycemia and type 1 diabetes with the risk of AF and then discuss the pathological role of AGE-RAGE axis in AF and its thromboembolic complications.

Glucose Management Technologies for the Critically Ill

Hyperglycemia is common in the intensive care unit (ICU) both in patients with and without a previous diagnosis of diabetes. The optimal glucose range in the ICU population is still a matter of debate. Given the risk of hypoglycemia associated with intensive insulin therapy, current recommendations include treating hyperglycemia after two consecutive glucose >180 mg/dL with target levels of 140-180 mg/dL for most patients. The optimal method of sampling glucose and delivery of insulin in critically ill patients remains elusive. While point of care glucose meters are not consistently accurate and have to be used with caution, continuous glucose monitoring (CGM) is not standard of care, nor is it generally recommended for inpatient use. Intravenous insulin therapy using paper or electronic protocols remains the preferred approach for critically ill patients. The advent of new technologies, such as electronic glucose management, CGM, and closed-loop systems, promises to improve inpatient glycemic control in the critically ill with lower rates of hypoglycemia.

Overall Quality of Care Predicts the Variability of Key Risk Factors for Complications in Type 2 Diabetes: An Observational, Longitudinal Retrospective Study

OBJECTIVE

An association between variability in clinical parameters (HbA_1c, blood pressure, cholesterol, and uric acid) and risk of complications in type 2 diabetes has been reported. In this analysis, we investigated to what extent such variability is associated with overall quality of care.

RESEARCH DESIGN AND METHODS

The quality of care summary score (Q-score) represents a validated, overall quality of care indicator ranging between 0 and 40; the higher the score, the better the quality of care provided by the diabetes center. We identified patients with five or more measurements of clinical parameters after the assessment of the Q-score. Multiple linear regression analyses assessed the role of the Q-score in predicting the variability of the different parameters.

RESULTS

Overall, 273,888 patients were analyzed. The variability of all the parameters systematically increased with decreasing Q-score values. At multivariate linear regression analysis, compared with a Q-score >25, a score <15 was associated with a significantly larger variation in HbA_1c, blood pressure, uric acid, total cholesterol, and LDL cholesterol and a lower variation in HDL cholesterol. The analysis of standardized β coefficients show that the Q-score has a larger impact on the variability of HbA_1c (0.34; P < 0.0001), systolic blood pressure (0.21; P < 0.0001), total cholesterol (0.21; P < 0.0001), and LDL cholesterol (0.20; P < 0.0001).

CONCLUSIONS

The variability of risk factors for diabetic complications is associated with quality of care. Quality of care improvement initiatives should be targeted to increase the achievement of the recommended target while reducing such variability.

Higher blood glucose and larger fluctuations detected postoperatively using continuous glucose monitoring: a preliminary study following total knee or hip arthroplasty

BACKGROUND

The control of diabetes mellitus (DM) should help reduce the incidence of periprosthetic joint infection (PJI). Self-monitoring of blood glucose (SMBG) concentration is usually undertaken at fixed time-points. Therefore, the extent of postoperative blood glucose fluctuation might be underestimated. To provide a more comprehensive assessment, continuous glucose monitoring (CGM) is beginning to be used. However, no previous studies have evaluated blood glucose concentrations using CGM following orthopedic surgery. Therefore, the differences between the maximum blood glucose concentrations measured using SMBG and CGM, and the mean amplitude of the glycemic fluctuation in patients with frank diabetes mellitus (DM) or pre-diabetes were evaluated. Blood glucose was measured in 20 patients who had undergone total hip or total knee arthroplasty (12 patients with DM and eight with pre-diabetes). Patients were fitted with a CGM device in the operating room, which was worn for 6 days postoperatively, and used to evaluate blood glucose concentration continuously. SMBG was performed simultaneously for the same period.

RESULTS

The mean difference between the maximum blood glucose concentrations measured using SMBG and CGM was 25.0 ± 20.3 mg/dl (range, - 17 to 81 mg/dl), with the concentrations measured using CGM tending to be higher than those measured using SMBG (P = 0.04). Blood glucose concentrations measured using CGM tended to be higher than those measured using SMBG until postoperative day 2, and to decrease gradually after postoperative day 4. There were no significant differences in the standard deviation of the blood glucose concentrations between the two groups.

CONCLUSIONS

Blood glucose concentrations > 200 mg/dl and larger fluctuations were more frequently recorded using CGM than SMBG, especially until postoperative day 2. Thus, CGM is more useful for the identification of high blood glucose concentrations and larger fluctuations. However, this information was not provided in real time.

Performance of a 2-step insulin infusion protocol with adjustment of insulin doses for Asians in the medical intensive care unit following cardiothoracic surgery

Background

Most previous insulin infusion protocols are titrated for Westerners and are not simple to follow. In this study, we tested the efficacy and safety of our simple insulin infusion protocol utilizing lower insulin doses for Asians.

Methods

A total of 152 patients with type 2 diabetes undergoing cardiothoracic surgery were included. After surgery, blood glucose (BG) was initially managed according to our algorithm protocol, and subsequently by the post-algorithm protocol. Insulin infusion rates in the algorithm protocol were titrated in two steps according to (1) current BG levels and (2) the difference between current and previous BG levels. In the post-algorithm protocol, insulin lispro was injected subcutaneously in addition to intravenous insulin infusion according to BG levels. The efficacy was assessed as achievement rates of two target BG ranges (140-199 and 80-199 mg/dL), and safety was assessed as hypoglycemia (< 70 mg/dL) and protocol error rates.

Results

With the use of the algorithm protocol, 58.7% of 1749 BG measurements achieved a range of 140-199 mg/dL, and 95.9% achieved levels within the 80-199 mg/dL range. Hypoglycemia and protocol error rates were 0.47 and 0.51%, respectively. With the post-algorithm protocol, 48.7 and 98.3% of 898 BG measurements achieved each target range. Hypoglycemia and protocol error rates were 0.78 and 0.22%, respectively. Severe hypoglycemia (< 40 mg/dL) was not observed.

Conclusions

Our insulin infusion protocol seems to be efficacious, safe, and widely feasible for Asian patients because of its simplicity and lower insulin dose.

Effects of Glucose Variability on Short-Term Outcomes in Non-Diabetic Patients After Coronary Artery Bypass Grafting: A Retrospective Observational Study

BACKGROUND

Postoperative hyperglycaemia has been shown to have adverse effects on patients after coronary artery bypass grafting surgery (CABG). However, whether glucose variability has an effect on patients' outcomes is still uncertain. The aim of this study is to explore the effects of glucose variability on short-term outcomes in non-diabetic patients undergoing coronary artery bypass grafting.

METHODS

This is a retrospective observational study utilising data collected after patients had left the hospital. This study was performed on 137 non-diabetic patients undergoing coronary artery bypass grafting from January 2011 to June 2013. Blood glucose at 72hours post operation was obtained and glucose variability was measured by mean postoperative blood glucose and mean of daily difference (MODD). Short-term outcomes included duration of intensive care unit (ICU) stay, mechanical ventilation time, length of hospital stay, and occurrence of arrhythmia. Patients with mean postoperative blood glucose ≥7.00mmol/L were defined as hyperglycaemic, and patients with MODD ≥1.40mmol/L were considered to be abnormal. Outcome variables were compared between patients in euglycaemic and hyperglycaemic groups, and between patients in normal and abnormal groups.

RESULTS

In our study, patients with hyperglycaemia spent more time staying in ICU (p<0.01), and patients with large glucose variability (abnormal MODD) had higher incidences of arrhythmia (23% vs 4.2%, p<0.05). Regression analysis showed that MODD can affect occurrence of arrhythmia (p=0.004) and that mean postoperative blood glucose levels can affect duration of ICU stay (p<0.001).

CONCLUSIONS

Patients' postoperative glucose variability after CABG is an important predictor of the negative outcomes regarding duration of ICU stay and occurrence of arrhythmia. Large glucose variability can have negative effects on short-term outcomes in patients.

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.