Perioperative glycemic control and its outcome in patients following open heart surgery

Lymphocyte Levels and Morbidity and Mortality in Cardiovascular Surgery With Cardiopulmonary Bypass

INTRODUCTION

A year ago, in a sample of 113 patients, our research group found that a high number of lymphocytes in the immediate postoperative period was correlated to a poor prognosis in cardiovascular surgeries. This study is an expansion of the initial study in order to confirm this finding.

METHODS

We analyzed the data of 338 consecutive patients submitted to cardiovascular surgeries with cardiopulmonary bypass performed at Hospital Universitário Ciências Médicas (Belo Horizonte/Brazil) from 2015 to 2017. We analyzed 39 variables with the outcomes death, hospital stay, and intensive care unit stay.

RESULTS

The value of lymphocytes in the immediate postoperative period > 2175.0/mm³ was an indicator of poor prognosis in this sample (P<0.001). The variables female sex, age, high level of European System for Cardiac Operative Risk Evaluation II, increased stay in the intensive care unit and in the ward, elevation of creatinine in the preoperative period and at intensive care unit discharge, elevation of the percentage of immediate postoperative period segmented neutrophils, high immediate postoperative period neutrophil/lymphocyte ratio, fasting hyperglycemia, preoperative critical condition, reintubation, mild or transient acute renal failure, surgical infection, cardiopulmonary bypass, and aortic cross-clamping and mechanical ventilation durations also had an impact on the mortality outcome.

CONCLUSION

The value of lymphocytes in the immediate postoperative period > 2175.0/mm3 was an indicator of poor prognosis in cardiovascular surgery with cardiopulmonary bypass.

Continuous Glucose Monitoring Using the Dexcom G6 in Cardiac Surgery During the Postoperative Period

OBJECTIVE

Cardiac surgery is associated with hyperglycemia, which in turn is associated with adverse postsurgical outcomes such as wound infections, acute renal failure, and mortality. This pilot study seeks to determine if Dexcom G6Pro continuous glucose monitor (Dexcom G6Pro CGM) is accurate during the postoperative cardiac surgery period when fluid shifts, systemic inflammatory response syndrome, and vasoactive medications are frequently encountered, compared to standard glucose monitoring techniques.

METHODS

This study received institutional review board approval. In this prospective study, correlation between clinical and Dexcom glucose readings was evaluated. Clinical glucose (blood gas, metabolic panel, and point of care) data set included 1428 readings from 29 patients, while the Dexcom G6Pro CGM data included 45 645 data points following placement to upper arm. Additionally, average clinical measurements of day and overnight temperatures and hemodynamics were evaluated. Clinical and Dexcom data were restricted to being at least 1 hour after prior clinical reading Matching Dexcom G6Pro CGM data were required within 5 minutes of clinical measure. Data included only if taken at least 2 hours after Dexcom G6Pro CGM insertion (warm-up time) and analyzed only following intensive care unit (ICU) admission. Finally, a data set excluding the first 24 hours after ICU admission was created to explore stability of the device. Patients remained on Dexcom G6Pro CGM until discharge or 10 days postoperatively.

RESULTS

The population was 71% male, 14% with known diabetes; 66% required intravenous insulin infusion. The Clarke error grid plot of all measures post-ICU admission showed 53.5% in zone A, 45.9% in zone B, and 0.6% (n = 5) in zones D or E. The restricted dataset that excluded the first 24 hours post-ICU admission showed 55.9% in zone A, 43.9% in zone B, and 0.2% in zone D. Mean absolute relative difference between clinical and Dexcom G6Pro CGM measures was 20.6% and 21.6% in the entire post-ICU admission data set, and the data set excluding the first 24 hours after ICU admission, respectively. In the subanalysis of the 12 patients who did not have more than a 5-minute tap in the operating room, a consensus error grid, demonstrated that after ICU admission, percentage in zone A was 53.9%, zone B 45.4%, and zone C 0.7%. Similar percentages were obtained removing the first 24 hours post-ICU admission. These numbers are very similar to the entire cohort. A consensus error grid created post-ICU admission demonstrated: (zone A) 54%, (zone B) 45%, (zone C) 0.9%, and the following for the dataset created excluding the first 24 hours: (zone A) 56%, (zone B) 44%, (zone C) 0.4%, which demonstrated very close agreement with the original Clarke error grid. No adverse events were reported.

CONCLUSIONS

Almost 100% of Dexcom G6Pro CGM and clinical data matching points fell within areas considered as giving clinically correct decisions (zone A) and clinically uncritical decisions (zone B). However, the relatively high mean absolute relative difference precludes its use for both monitoring and treatment in the clinical context. As technology evolves, interstitial glucose monitoring may become an important tool to limit iatrogenic anemia and mitigate glycemic fluctuations.

Prevalence of diabetes mellitus in patients undergoing coronary artery bypass grafting in a Tertiary Care Hospital

Objective

To find out the prevalence of diabetes mellitus in patients undergoing coronary artery bypass grafting (CABG).

Methods

This retrospective study was conducted in Northwest General Hospital and Research center Hayatabad, Peshawar over a duration of 15 months (December 2020 - March 2022). Every patient was tested through regular laboratory investigations. Diabetes mellitus was established according to WHO standards of fasting plasma glucose >126 mg/dl or two hours postprandial glucose level of 200 mg/dl. Data were analyzed using SPSS. Mean and standard deviation was used for quantitative data. Frequency and percentages were used for qualitative data. Shapiro Wilk's test was done to find the normality of the data.

Results

Out of a total of 360 candidates, 129 (36%) individuals were non-diabetic and 231 (64%) candidates were diabetic. Among the diabetic patients, 64 (28%) were female and 167 (72%) were males with a ratio of 1:2.6 respectively.

Conclusion

Prevalence of diabetes was 64% among the CABG population. Since the prevalence of diabetes can significantly affect the outcomes of people undergoing CABG, it is essential to generate awareness regarding diabetes among healthcare workers as well as the general population. More extensive research is needed to be carried by various health care centers to figure out the prevalence of diabetes mellitus in cardiac surgery patients.

Surgical Site Infections and Inflammatory Reaction After Cardiac Surgery; Bedside Artificial Pancreas Versus Conventional Insulin Therapy: A Propensity Score-Matched Analysis

OBJECTIVES

Perioperative hyperglycemia is associated with poor postoperative recovery, including compromised immune function and increased risk of infection. A closed-loop glycemic control system (artificial pancreas) has demonstrated strict safe perioperative glycemic control without hypoglycemia risk. The authors hypothesized that the artificial pancreas would reduce surgical site infections (SSIs) and postoperative inflammatory reactions. This study aimed to assess the effect of the artificial pancreas on SSIs and C-reactive protein (CRP) levels after cardiac surgery.

DESIGN

A single-center retrospective, propensity score-matched analysis.

SETTING

A university hospital.

PARTICIPANTS

In total, 295 patients who underwent cardiovascular surgery with cardiopulmonary bypass were included.

INTERVENTIONS

Patients were divided into two groups: artificial pancreas (target blood glucose: 120-150 mg/dL) and intravenous insulin infusion (conventional insulin therapy, target blood glucose: <200 mg/dL).

MEASUREMENTS AND MAIN RESULTS

The differences in the incidence of SSIs and CRP levels between the two groups were assessed. After 1:1 propensity score matching based on their covariates, 101 matched patients were selected from each group. The incidence of SSIs was reduced by 3%, 5% (conventional insulin therapy), and 2% (artificial pancreas), but the reduction was not statistically significant (p = 0.45). The postoperative maximum CRP level was significantly lower in the artificial pancreas group than in the conventional insulin therapy group, mean (standard deviation)14.53 (5.64) mg/dL v 16.57 (5.58) mg/dL; p = 0.01.

CONCLUSIONS

The artificial pancreas did not demonstrate a significant reduction in the incidence of SSIs. However, the artificial pancreas was safe and suppressed postoperative inflammation compared with conventional insulin therapy.