Comparison of mechanisms underlying changes in glucose utilization in fasted rats anesthetized with propofol or sevoflurane: Hyperinsulinemia is exaggerated by propofol with concomitant insulin resistance induced by an acute lipid load

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.

Metabolomics and Whole-Exome Sequencing in Patients with Differential Sensitivity to Sevoflurane: A Protocol for a Prospective Observational Trial

Introduction: Different sensitivity to volatile anesthetics in Drosophila, nematodes and mice is related to mutation of energy metabolism genes. In clinical practice, we find that the end-tidal sevoflurane concentration (ET_sevo) differs among patients at the same depth of anesthesia, indicating that the sensitivity to sevoflurane varies among patients. However, the underlying mechanism remains unclear. The sensitivity of an anesthetic is associated with the postoperative outcomes of patients and the mechanism of action of volatile anesthetics. We therefore propose this protocol to determine whether differences in metabolite profile and genetic variations contribute to patients' sensitivity to volatile anesthetics. Methods and Analysis: This is a single-centre, prospective observational study. 720 patients undergoing abdominal surgery were included. General anesthesia was induced with inhaled sevoflurane, a bolus of sufentanil (0.2-0.4 μg/kg) and cis-atracurium (0.2-0.3 mg/kg). The end-tidal sevoflurane concentration (ET_sevo) was adjusted to maintain a BIS (bispectral index) value between 40-60. The mean ET_sevo from 20 min after endotracheal intubation to 2 h after the beginning of surgery (steady state) was calculated for each patient. Patients were further divided into a high-sensitivity group (mean ET_sevo - SD) and a low-sensitivity group (mean ET_sevo + SD) to investigate the sensitivity to sevoflurane. Cases were paired from the high-sensitivity group (group H) and low-sensitivity group (group L) according to age, sex, body mass index (BMI), ASA physical status classification, vital signs, BIS, ephedrine use, sufentanildose, and cis-atracurium dose at anesthesia induction and steady state. Differences in metabolite levels, single nucleotide polymorphisms (SNPs) and protein-coding gene sequence variations between group H and group L will be determined through plasma metabolomics, whole-exome sequencing (WES), genome-wide association study (GWAS), and bioinformatics analyses. These results will be analysed to determine the reasons for the differential sensitivity to sevoflurane in humans. Ethics and Dissemination: This prospective observational study protocol has received ethical approval from the Ethical Committee of West China Hospital of Sichuan University on May 19, 2017 (Approval No. 78). Informed consent will be obtained before patient enrolment. The results will be submitted to international peer-review journals. Trial Registration Number: ChiCTR1800014327.

Effects of sevoflurane anesthesia and abdominal surgery on the systemic metabolome: a prospective observational study

Background

Metabolic status can be impacted by general anesthesia and surgery. However, the exact effects of general anesthesia and surgery on systemic metabolome remain unclear, which might contribute to postoperative outcomes.

Methods

Five hundred patients who underwent abdominal surgery were included. General anesthesia was mainly maintained with sevoflurane. The end-tidal sevoflurane concentration (ET_sevo) was adjusted to maintain BIS (Bispectral index) value between 40 and 60. The mean ET_sevo from 20 min after endotracheal intubation to 2 h after the beginning of surgery was calculated for each patient. The patients were further divided into low ET_sevo group (mean − SD) and high ET_sevo group (mean + SD) to investigate the possible metabolic changes relevant to the amount of sevoflurane exposure.

Results

The mean ET_sevo of the 500 patients was 1.60% ± 0.34%. Patients with low ET_sevo (n = 55) and high ET_sevo (n = 59) were selected for metabolomic analysis (1.06% ± 0.13% vs. 2.17% ± 0.16%, P < 0.001). Sevoflurane and abdominal surgery disturbed the tricarboxylic acid cycle as identified by increased citrate and cis-aconitate levels and impacted glycometabolism as identified by increased sucrose and D-glucose levels in these 114 patients. Glutamate metabolism was also impacted by sevoflurane and abdominal surgery in all the patients. In the patients with high ET_sevo, levels of L-glutamine, pyroglutamic acid, sphinganine and L-selenocysteine after sevoflurane anesthesia and abdominal surgery were significantly higher than those of the patients with low ET_sevo, suggesting that these metabolic changes might be relevant to the amount of sevoflurane exposure.

Conclusions

Sevoflurane anesthesia and abdominal surgery can impact principal metabolic pathways in clinical patients including tricarboxylic acid cycle, glycometabolism and glutamate metabolism. This study may provide a resource data for future studies about metabolism relevant to general anaesthesia and surgeries.

Trial registration

www.chictr.org.cn. identifier: ChiCTR1800014327.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-021-01301-0.

Randomized Trial to Compare Plasma Glucose Trends in Patients Undergoing Surgery for Supratentorial Gliomas under Maintenance of Sevoflurane, Desflurane, and Propofol

Background

Anesthetic agents influence the glycemic response by affecting the neuroendocrine surgical response or directly modifying pancreatic insulin release. Due to chances of neuronal damage, intraoperative hyperglycemia and hypoglycemia both are detrimental for patients undergoing neurosurgeries. Inhalational (sevoflurane and desflurane) and intravenous (propofol) agents have been found to raise intraoperative glucose levels in nonneurological surgeries.

Aim

We aimed to compare the intraoperative glucose levels in supratentorial glioma surgeries under the maintenance of three anesthetic agents such as sevoflurane, desflurane, and propofol.

Materials and Methods

This randomized trial was conducted with 90 nondiabetic adults with supratentorial glioma. Thirty patients were allocated randomly to the three groups receiving sevoflurane, desflurane, and propofol. Baseline and hourly plasma glucose levels were recorded. Postoperatively, the time required to achieve an Aldrete score of 9 and complications were assessed.

Results

Baseline plasma glucose levels were 111.23 ± 11.67, 109.47 ± 19.75, and 111.7 ± 13.88 mg/dL (P = 0.84) in sevoflurance, desflurane, and propofol group, respectively. All of them showed an elevation of plasma glucose in relation to the time of surgery with variable trends. In the 4^th and 5^th h, the elevations in the inhalational groups (sevoflurane and desflurane) were significantly higher than the propofol group (P = 0.003 and 0.002, respectively). The time for achieving Aldrete's score of 9 was higher in the propofol group (P < 0.0001). No differences were observed in the duration of hospital stay or complications.

Conclusions

Maintenance of anesthesia in nondiabetic patients showed clinically modest rise of plasma glucose which is higher in patients under sevoflurane and desflurane than under propofol. However, the immediate recovery was faster with inhalational agents compared to propofol-based anesthesia.

Propofol Improved Glucose Tolerance Associated with Increased FGF-21 and GLP-1 Production in Male Sprague-Dawley Rats

Anesthetics, particularly volatile anesthetics, have been shown to impair glucose metabolism and cause hyperglycemia, closely linking them with mortality and morbidity as related to surgery. Beyond being an anesthetic used for general anesthesia and sedation, intravenous hypnotic propofol displays an effect on glucose metabolism. To extend the scope of propofol studies, its effects on glucose metabolism were evaluated in male Sprague-Dawley rats of various ages. Unlike chloral hydrate and isoflurane, propofol had little effect on basal glucose levels in rats at 2 months of age, although it did reduce chloral hydrate- and isoflurane-induced hyperglycemia. Propofol reduced postload glucose levels after either intraperitoneal or oral administration of glucose in both 7- and 12-month-old rats, but not those at 2 months of age. These improved effects regarding propofol on glucose metabolism were accompanied by an increase in insulin, fibroblast growth factor-21 (FGF-21), and glucagon-like peptide-1 (GLP-1) secretion. Additionally, an increase in hepatic FGF-21 expression, GLP-1 signaling, and FGF-21 signaling, along with a decrease in endoplasmic reticulum (ER) stress, were noted in propofol-treated rats at 7 months of age. Current findings imply that propofol may turn into insulin-sensitizing molecules during situations of existing insulin resistance, which involve FGF-21, GLP-1, and ER stress.

Postoperative hunger after outpatient surgery in patients anesthetized with propofol vs sevoflurane: a randomized-controlled trial

PURPOSE

Previous preclinical and preliminary clinical data suggest an appetite-stimulating effect of propofol compared with halogenated drugs. This study compared the effects of propofol with those of sevoflurane on recovery of hunger during the postoperative period.

METHODS

Patients undergoing outpatient transvaginal oocyte retrieval were randomized to propofol-remifentanil (propofol group) or sevoflurane-remifentanil (sevoflurane group) anesthesia. The primary endpoint was the time before feeling hungry (≥ 50/100 mm on a visual analogue scale). Secondary endpoints included plasma levels of ghrelin, leptin, and insulin (ten minutes, one hour, and two hours after anesthesia), caloric intake at first feed, and discharge readiness time.

RESULTS

In the 58 patients allocated to either the propofol or sevoflurane group, there was no difference in the median [interquartile range] recovery time of hunger (97 [75-138] vs 97 [80-140] min, respectively; median difference, 1; 95% confidence interval [CI], - 15 to 14; P = 0.91); caloric intake (245 [200-343] vs 260 [171-314] kcal; P = 0.39); or discharge readiness time (125 [85-153] vs 125 [95-174] min, P = 0.29). The groups showed no difference in crude plasma levels of ghrelin, leptin, and insulin at any time-point. When peptide plasma levels were expressed as a % change from baseline, there was a higher insulin plasma level one hour after anesthesia in the sevoflurane group (median difference, 4.9%; 95% CI, - 16.2 to 43.4) compared with the propofol group (median difference, - 21.2%; 95% CI, - 35.7 to 9.1; adjusted P = 0.01).

CONCLUSION

Propofol did not accelerate the recovery of hunger compared with sevoflurane after outpatient minor surgery. Moreover, propofol did not have distinguishable effects on other clinical or biological parameters associated with food intake.

TRIAL REGISTRATION

www.ClinicalTrials.gov (NCT02272166); registered 22 October, 2014.

Propofol inhibits stromatoxin-1-sensitive voltage-dependent K+ channels in pancreatic β-cells and enhances insulin secretion

Background

Proper glycemic control is an important goal of critical care medicine, including perioperative patient care that can influence patients’ prognosis. Insulin secretion from pancreatic β-cells is generally assumed to play a critical role in glycemic control in response to an elevated blood glucose concentration. Many animal and human studies have demonstrated that perioperative drugs, including volatile anesthetics, have an impact on glucose-stimulated insulin secretion (GSIS). However, the effects of the intravenous anesthetic propofol on glucose metabolism and insulin sensitivity are largely unknown at present.

Methods

The effect of propofol on insulin secretion under low glucose or high glucose was examined in mouse MIN6 cells, rat INS-1 cells, and mouse pancreatic β-cells/islets. Cellular oxygen or energy metabolism was measured by Extracellular Flux Analyzer. Expression of glucose transporter 2 (GLUT2), potassium channels, and insulin mRNA was assessed by qRT-PCR. Protein expression of voltage-dependent potassium channels (Kv2) was also assessed by immunoblot. Propofol’s effects on potassium channels including stromatoxin-1-sensitive Kv channels and cellular oxygen and energy metabolisms were also examined.

Results

We showed that propofol, at clinically relevant doses, facilitates insulin secretion under low glucose conditions and GSIS in MIN6, INS-1 cells, and pancreatic β-cells/islets. Propofol did not affect intracellular ATP or ADP concentrations and cellular oxygen or energy metabolism. The mRNA expression of GLUT2 and channels including the voltage-dependent calcium channels Cav1.2, Kir6.2, and SUR1 subunit of K_ATP, and Kv2 were not affected by glucose or propofol. Finally, we demonstrated that propofol specifically blocks Kv currents in β-cells, resulting in insulin secretion in the presence of glucose.

Conclusions

Our data support the hypothesis that glucose induces membrane depolarization at the distal site, leading to K_ATP channel closure, and that the closure of Kv channels by propofol depolarization in β-cells enhances Ca²⁺ entry, leading to insulin secretion. Because its activity is dependent on GSIS, propofol and its derivatives are potential compounds that enhance and initiate β-cell electrical activity.

Comparison of sevoflurane and propofol anesthesia on the incidence of hyperglycemia in patients with type 2 diabetes undergoing lung surgery

Background

The type and regimen of anesthesia may affect perioperative hyperglycemia following major surgical stress. This study compared the effects of sevoflurane and propofol on the incidence of hyperglycemia and clinical outcomes in diabetic patients undergoing lung surgery.

Methods

This retrospective study included 176 patients with type 2 diabetes mellitus who had undergone lung surgery. Blood glucose levels and clinical outcomes from the preoperative period to the first 2 post-operative days (PODs) were retrospectively examined in patients who received sevoflurane (group S, n= 87) and propofol (group P, n=89) for maintenance of general anesthesia. The primary endpoint was the incidence of persistent hyperglycemia (2 consecutive blood glucose levels >180 mg/dL [10.0 mmol/L]) during the perioperative period. The secondary composite endpoint was the incidence of major postoperative complications and 30-day mortality rate after surgery.

Results

Blood glucose levels similarly increased from the preoperative period to the second POD in both groups (p=0.857). Although blood glucose levels at 2 hours after surgery were significantly lower in group P than in group S (p=0.022; 95% confidence interval for mean difference, -27.154 to -2.090), there was no difference in the incidence of persistent hyperglycemia during the perioperative period (group S, 70%; group P, 69%; p=0.816). The composite of major postoperative complications and all-cause in-hospital and 30-day mortality rates were also comparable between the two groups.

Conclusion

Sevoflurane and propofol were associated with a comparable incidence of perioperative hyperglycemia and clinical outcomes in diabetic patients undergoing lung surgery.