Safety of intranasal insulin administration in patients undergoing cardiovascular surgery: An open-label, nonrandomized, dose-escalation study.

Objective: This study aimed to determine the maximum safe dose of intranasal insulin administration during cardiac surgery. Methods: This open-label, Phase 1, single-center, dose-escalation clinical trial recruited patients scheduled to undergo elective cardiac surgery or major vascular surgery requiring cardiopulmonary bypass between February and September 2021. They were grouped into 5 dose-escalation cohorts and administered 0, 40, 80, 160, and 240 IU insulin (n = 6 in each group) via a metered nasal dispenser after the induction of general anesthesia. Blood samples were collected at 10-minute intervals for the first 60 minutes and at 30-minute intervals thereafter. Hypoglycemia was defined as a blood glucose level <70 mg/dL. Patient recruitment was terminated after hypoglycemia was observed in 2 patients in any of the groups. Results: In total, 27 of 29 enrolled patients were administered intranasal insulin or saline. Hypoglycemia was not observed after the administration of intranasal insulin in the 0, 40, 80, or 160 IU groups; however, it was observed in 2 of 3 patients in the 240 IU group. The serum insulin concentration was elevated in the 160-IU group, but the C-peptide concentration was not elevated in any of the groups. Conclusions: The administration of up to 160 IU intranasal insulin did not induce clinically significant hypoglycemia. However, 160 IU intranasal insulin should be administered cautiously because insulin can enter the systemic circulation in a dose-dependent manner.

Accuracy of the Nova StatStrip® glucometer in patients undergoing major abdominal surgery: an observational study.

PURPOSE: While the Nova StatStrip® Glucose Hospital Meter System (Nova Biomedical, Waltham, MA, USA) is approved for point-of-care testing (POCT) in critically ill patients, its use during major abdominal surgery has not been evaluated. The purpose of this study was to assess the accuracy of the Nova StatStrip glucometer in patients undergoing major hepatobiliary procedures using the Parkes error grid (ISO15197:2013) and criteria defined by the Clinical and Laboratory Standards Institute (CLSI) POCT12-A3 guideline. METHODS: This study was a post hoc exploratory study of patients participating in a prospective randomized controlled trial on the effects of hyperinsulinemic normoglycemia (HNC) on infectious outcomes after hepatobiliary surgery. Arterial blood samples were collected before surgery and one hour, two hours, and three hours after baseline. Blood glucose levels were analyzed by the Nova StatStrip glucometer and the GEM® PremierTM 5000 blood gas analyzer. Accuracy of the StatStrip glucometer was assessed using the Parkes error grid for type 1 diabetes mellitus (when 99% of samples were within zones A and B on the Parkes error grid and clinical accuracy was acceptable) and the CLSI POCT12-A3 criteria. RESULTS: Blood glucose levels were analyzed in 135 patients, 70 of whom received the HNC. In the Parkes error grid plotted, all samples at all time-points were within zones A and B. The Nova StatStrip glucometer also satisfied CLSI POCT12-A3 criteria at all time-points. CONCLUSION: The Nova StatStrip glucometer was accurate in patients undergoing major upper abdominal surgery, independent of the administration of high-dose insulin therapy. STUDY REGISTRATION: ClinicalTrials.gov (NCT01528189); registered 7 February 2012.

RéSUMé: OBJECTIF: Bien que le système hospitalier de lecture de la glycémie StatStrip® de Nova (Nova Biomedical, Waltham, MA, É.-U.) soit approuvé pour une utilisation au chevet (ou POCT, pour 'Point of Care Testing') chez la patientèle en état critique, son utilisation n'a pas été évaluée en chirurgie abdominale majeure. L'objectif de cette étude était d'évaluer la précision du glucomètre StatStrip de Nova chez la patientèle bénéficiant d'interventions hépatobiliaires majeures à l'aide de la grille d'erreur de Parkes (ISO15197:2013) et des critères définis par la directive POCT12-A3 du Clinical and Laboratory Standards Institute (CLSI). MéTHODE: Il s'agissait d'une étude exploratoire post-hoc auprès de patient·es participant à une étude randomisée contrôlée prospective sur les effets de la normoglycémie hyperinsulinémique (HNC) sur les issues infectieuses après une chirurgie hépatobiliaire. Des échantillons de sang artériel ont été prélevés avant la chirurgie et une heure, deux heures et trois heures après l'échantillon initial. Les taux de glycémie ont été analysés avec le glucomètre StatStrip de Nova et l'analyseur de gaz sanguin GEM® PremierTM 5000. La précision du glucomètre StatStrip a été évaluée à l'aide de la grille d'erreur de Parkes pour le diabète sucré de type 1 (lorsque 99 % des échantillons se trouvaient dans les zones A et B de la grille d'erreur de Parkes et que la précision clinique était acceptable) et des critères POCT12-A3 du CLSI. RéSULTATS: La glycémie a été analysée chez 135 personnes, dont 70 ont reçu une normoglycémie hyperinsulinémique. Dans la grille d'erreur de Parkes tracée, tous les échantillons à tous les points temporels se trouvaient dans les zones A et B. Le glucomètre StatStrip de Nova a également satisfait aux critères POCT12-A3 du CLSI à tous les points temporels. CONCLUSION: Le glucomètre StatStrip de Nova était précis chez la patientèle bénéficiant d'une chirurgie abdominale supérieure majeure, indépendamment de l'administration d'insulinothérapie à forte dose. ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov (NCT01528189); enregistrée le 7 février 2012.

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.

Role of the protein kinase A signaling pathway and identification of mediators in the cardioprotective effects of enteral lactoferrin for ischemia-reperfusion injury in an isolated rat heart model.

OBJECTIVE: Lactoferrin is an iron-binding glycoprotein. Enteral lactoferrin attenuates myocardial ischemia-reperfusion (IR) injury, but the underlying mechanism remains unknown. The aim of this study was to investigate protein kinase A (PKA) signaling pathway activation and levels of serum glucagonlike peptide-1 (GLP-1), secreted by intestinal endocrine L cells, and adiponectin, secreted by adipose tissue, after enteral lactoferrin administration. METHODS: Hearts (N = 32) were excised from Wistar rats and perfused using a Langendorff system. To assess the role of the PKA pathway in the cardioprotective effects of lactoferrin, an inhibitor of PKA (H89) was applied before no-flow ischemia. Rats were randomly divided into four groups: control, lactoferrin (LF), control+H89, and LF+H89. The control and control+H89 groups were administered normal saline by gavage, and the LF and L +H89 groups were administered bovine lactoferrin (1000 mg/kg) by gavage 15 min before intraperitoneal pentobarbital injection. Muscle sampling was performed at the end of reperfusion. When rats were sacrificed, blood was sampled to measure hormone levels. The primary outcome was maximum left ventricular pressure derivative (LV dP/dt max) 15 min after reperfusion. RESULTS: LV dP/dt max at 10 and 15 min after reperfusion was significantly higher in the LF group than in the control group (P < 0.05), and the effect was diminished by H89. The PKA pathway was significantly activated in the LF group. Enteral lactoferrin increased serum GLP-1 but not serum adiponectin levels. CONCLUSIONS: Enteral lactoferrin induces cardioprotective effects against myocardial IR injury via the PKA signaling pathway and increases serum GLP-1 levels.

Randomized controlled trial of the effect of hyperinsulinemic normoglycemia during liver resection on postoperative hepatic function and surgical site infection.

Background: While avoidance of preoperative fasting followed by hyperinsulinemic-normoglycemic clamp (HNC) reduced postoperative hepatic dysfunction and surgical site infection (SSI), the effect of HNC restricted to the intraoperative period is unknown. This study examined whether HNC restricted to the intraoperative period has similar effects in patients undergoing elective liver resections. Methods: This study is a post hoc exploratory analysis of a randomized-controlled trial in patients undergoing hepatobiliary surgery and receiving the HNC as a potential preventative intervention to reduce infectious morbidity postoperatively. Patients (>18 years old) undergoing elective transabdominal resection of liver malignancy were enrolled. We implemented the random allocation by labelling cards. Consenting patients were randomly assigned to receive the HNC during surgery or standard metabolic care. The HNC was initiated by insulin (2 mU/kg/min) followed by 20% dextrose infusion titrated to keep blood glucose between 4.0 and 6.0 mmol/L until the end of surgery. In the control group, glycemia >10.0 mmol/L prompted insulin treatment according to a standardized sliding scale. The primary outcome was hepatic function on postoperative day (POD) one, assessed by Schindl score. Secondary outcome was the incidence of SSIs within 30 days after surgery. The Schindl score was analyzed by Mann-Whitney U test and the incidence of SSIs was analyzed by Fisher's exact test. Two-sided P values <0.05 were considered statistically significant. Results: From October 2018 to May 2022, 32 patients in the control group and 34 patients in the HNC group were analyzed. Patient characteristics were similar in the two groups. There was no significant difference in the mean Schindl score on POD1 between the HNC group and the control group (0.8±0.9 vs. 1.2±1.6, P=0.61). However, the incidence of SSIs in the HNC group was significantly lower than in the control group (6% vs. 31%, P=0.01). Conclusions: The HNC restricted to the intraoperative period did not improve postoperative hepatic function but reduced SSIs. Preoperative carbohydrate loading may contribute to the preservation of hepatic function. Trial Registration: ClinicalTrials.gov NCT01528189.

Cardioprotective effects of enteral vs. parenteral lactoferrin administration on myocardial ischemia-reperfusion injury in a rat model of stunned myocardium.

BACKGROUND: Lactoferrin, an iron-binding glycoprotein, is known to have protective effects against intestinal and cerebral ischemia-reperfusion (IR) injuries; however, its cardioprotective effects against the stunned myocardium are unknown. This study aimed to test the hypothesis that lactoferrin has cardioprotective effects against stunned myocardium. METHODS: Using isolated rat hearts (Langendorff system), we determined the effects of lactoferrin administered enterally and by direct cardiac perfusion. Rat hearts were perfused using the Langendorff system, and two experiments were performed. In experiment 1, the hearts were divided into the enteral lactoferrin (E-LF) 7.5 m, 15 m, 30 m, and 60 m groups, where lactoferrin (1000 mg/kg) was administered enterally 7.5, 15, 30, and 60 min, respectively, before perfusion; and a control group, where saline was administered 30 min before perfusion. In experiment 2, hearts were allocated to the perfusate lactoferrin (P-LF) 15 and 100 groups, where 15 mg/L and 100 mg/L lactoferrin were respectively added to the perfusate, and a control group. Each group was perfused for 20 min prior to 15 min of no-flow ischemia with pacing, followed by 20 min of reperfusion. The primary outcome was the maximum left ventricular derivative of pressure development (LV dP/dt max) 15 min after reperfusion. Myocardial phospho-protein kinase B (p-Akt) was assayed using western blotting. RESULTS: The LV dP/dt max 15 min after reperfusion in the E-LF 15 and 30 m groups was significantly higher than that in the control group. However, the effects disappeared in the E-LF 60 m group. In the second experiment, there were no significant differences in LV dP/dt max. Myocardial p-Akt was not significantly activated in any lactoferrin group. CONCLUSION: Cardioprotection was observed 15-30 min after enteral lactoferrin but not by direct cardiac perfusion with lactoferrin. Myocardial p-Akt was not associated with the cardioprotective effect. The cardioprotective effect may be induced by enteral lactoferrin-induced substances.

PI3K/Akt pathway mediates the positive inotropic effects of insulin in Langendorff-perfused rat hearts.

Insulin exerts positive inotropic effects on cardiac muscle; however, the relationship between cardiac contractility and phosphoinositol-3-kinase/Akt (PI3K/Akt) activation remains unclear. We hypothesized that the positive inotropic effects of insulin are dose-dependent and mediated via the PI3K/Akt pathway in isolated normal rat hearts. The Institutional Animal Investigation Committee approved the use of hearts excised from rats under pentobarbital anesthesia. The hearts were perfused at a constant pressure using the Langendorff technique. After stabilization (baseline), the hearts were randomly divided into the following four insulin (Ins) groups: 1) Ins0 (0 IU/L), 2) Ins0.5 (0.5 IU/L), 3) Ins5 (5 IU/L), and 4) Ins50 (50 IU/L) (n = 8 in each group). To clarify the role of the PI3K/Akt pathway in insulin-dependent inotropic effects, we also treated the insulin groups with the PI3K inhibitor wortmannin (InsW): 5) InsW0 (0 IU/L), 6) InsW0.5 (0.5 IU/L), 7) InsW5 (5 IU/L), and 8) InsW50 (50 IU/L). Hearts were perfused with Krebs-Henseleit buffer solution with or without wortmannin for 10 min, followed by 20 min perfusion with the solution containing each concentration of insulin. The data were recorded as the maximum left ventricular derivative of pressure development (LV dP/dt max). Myocardial p-Akt levels were measured at 3 min, 5 min, and at the end of the perfusion. In the Ins groups, LV dP/dt max in Ins5 and Ins50 increased by 14% and 48%, respectively, 3 min after insulin perfusion compared with the baseline. Tachyphylaxis was observed after 10 min in the Ins5 and Ins50 treatment groups. Wortmannin partially inhibited the positive inotropic effect of insulin; although insulin enhanced p-Akt levels at all time points compared with the control group, this increase was suppressed in the presence of wortmannin. The positive inotropic effect of insulin is dose-dependent and consistent with Akt activation. This effect mediated by high doses of insulin on cardiac tissue was temporary and caused tachyphylaxis, potentially triggered by Akt overactivation, which leads beta 1 deactivation.

Albumin and fibrinogen kinetics in sepsis: a prospective observational study.

BACKGROUND: The measurement of circulating substrate concentrations does not provide information about substrate kinetics. It, therefore, remains unclear if a decrease in plasma concentration of albumin, as seen during critical illness, is a consequence of suppressed production in the liver or increased peripheral clearance. In this study, using stable isotope tracer infusions, we measured albumin and fibrinogen kinetics in septic patients and in a control group of non-septic subjects. METHODS: With the approval from the institutional Research Ethics Board and after obtaining written informed consent from patients or their substitute decision maker, mechanically ventilated patients with sepsis and patients scheduled for elective coronary artery bypass grafting were enrolled. Patients in the non-sepsis group were studied on the day before surgery. The stable isotope L-[ring-2H5]phenylalanine was used to measure absolute synthesis rates (ASR) of albumin and fibrinogen. A priming dose of L-[ring-2H5]phenylalanine (4 µmol/kg) was given followed by a six-hour infusion at a rate of 0.15 µmol/kg/min. At baseline and hourly thereafter, blood was drawn to measure isotope enrichments by gas chromatography/mass spectrometry. Very low density lipoprotein apolipoprotein-B 100 isotopic enrichment was used to represent the isotopic enrichment of the phenylalanine precursor pool from which the liver synthesizes proteins. Plasma albumin and fibrinogen concentrations were also measured. RESULTS: Mean plasma albumin in septic patients was decreased when compared to non-septic patients, while synthesis rates were comparable. Mean plasma fibrinogen and ASR in septic patients was increased when compared to non-septic patients. In non-septic patients, no statistically significant correlation between plasma albumin and ASR was observed but plasma fibrinogen significantly correlated with ASR. In septic patients, plasma albumin and fibrinogen significantly correlated with ASR. CONCLUSIONS: While septic patients showed lower plasma albumin levels than non-septic patients, albumin synthesis was similar in the two groups suggesting that hypoalbuminemia during sepsis was not caused by suppressed hepatic production but a result of enhanced clearance from the circulation. Hyperfibrinogenemia in septic patients was a consequence of increased fibrinogen production. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02865408 (registered on August 12, 2016) and ClinicalTrials.gov: NCT02549443 (registered on September 15, 2015).

Ulinastatin attenuates protamine-induced cardiotoxicity in rats by inhibiting tumor necrosis factor alpha.

Protamine causes cardiac depression, which may be mediated by tumor necrosis factor alpha (TNF-α). Ulinastatin, a human urinary protease inhibitor, inhibits TNF-α. Here, we aimed to investigate whether ulinastatin prevented protamine-induced myocardial depression by inhibiting TNF-α. Rat hearts were perfused using a Langendorff system, and three protocols were followed. Protocol 1: The hearts were divided into saline, ulinastatin-low, and ulinastatin-high groups. Protamine was administered to each group, and myocardial contractility was the primary outcome. Protocol 2: The hearts were allotted to saline or ulinastatin group. Protamine was administered to each group. TNF-α expression in the coronary effluent and myocardial tissue was measured. Protocol 3: The hearts were allotted to saline and ulinastatin groups. Recombinant rat-TNF-α was administered to each group. Protamine alone reduced the maximum left ventricular pressure derivative (LV dP/dt max) by 45 ± 4%. In contrast, the reduction in LV dP/dt max was 4 ± 3% in the ulinastatin-high group. Compared with that in the saline group, the increase in TNF-α in the coronary effluent was attenuated in the ulinastatin group. Recombinant TNF-α alone reduced LV dP/dt max (- 21 ± 14%). In contrast, when TNF-α was added in the presence of ulinastatin, the decrease in LV dP/dt max was prevented significantly (- 3 ± 8%). We showed, for the first time, that ulinastatin protected against protamine-induced myocardial damage, both by inhibiting TNF-α synthesis and by directly preventing the cardiodepressant action of TNF-α.

Anesthetic management of a child with catecholaminergic polymorphic ventricular tachycardia undergoing insertion of implantable cardioverter defibrillator : a case report.

BACKGROUND: Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a fatal cardiac ion channelopathy that causes sudden unexpected death in the young. CASE PRESENTATION: The patient was a 3-year-old girl with CPVT. Insertion of an implantable cardioverter defibrillator (ICD) using epicardial pacing was scheduled. After premedication of rectal midazolam was given, general anesthesia was induced with midazolam, fentanyl, and rocuronium, and maintained with midazolam, fentanyl, remifentanil, and rocuronium. The operation was performed without any complications. Dexmedetomidine and fentanyl were continuously infused after the operation until she was extubated in the morning of postoperative day 1. Fatal arrhythmia due to perioperative stress did not occur. CONCLUSIONS: We report the anesthetic management of a child with CPVT who underwent insertion of an ICD. CPVT-induced fatal arrhythmia did not occur perioperatively by carefully avoiding perioperative stress with premedication and post-operative sedation.

[Anesthesia for a Patient with Acute Appendicitis and Idiopathic Cervical Internal Carotid Artery Vasospasms].

A 33 year-old female patient was admitted to the hospital with acute appendicitis. She had idiopathic cervical internal carotid artery vasospasms and had been taking aspirin. We used intracranial oxygen saturation measuring instrument (INVOS®) for anesthetic management during general anesthesia. We administered atropine and continuous small amount of dopamine, and loaded fluids when her blood pressure decreased. We refrained from using medicines which might influence cerebral blood flows. Intracranial oxygen saturation was maintained above baseline during the operation. Intracranial oxygen saturation measuring instrument was useful in achieving the maintenance of intracranial environment Administration of dopamine and atropine was useful and safe in keeping the circulation dynamics and intracranial tissue oxygen saturation in this patient.