Ketamine as an Alternative Anesthetic for Augmenting Seizure Durations During Electroconvulsive Therapy: A Retrospective Observational Study.

OBJECTIVE: Electroconvulsive therapy (ECT) is highly effective for severe psychiatric disorders; however, short seizure durations may lead to ineffective therapy. This retrospective study aimed to examine the risks and benefits of switching to ketamine anesthesia to augment seizure durations during an acute course of ECT. METHODS: We included 33 patients who underwent ketamine anesthesia due to suboptimal seizures during an acute course of ECT. We assessed seizure duration, stimulus dose, hemodynamic variability, and postseizure complications before and after switching to ketamine. RESULTS: Age was significantly associated with suboptimal seizures during ECT ( P = 0.040). After switching to ketamine, 32 patients (97%) experienced prolonged seizure duration. Ketamine significantly prolonged both electroencephalogram and motor seizure durations with a mean difference of 34.6 seconds (95% confidence interval [CI], 26.4-42.7 seconds; P < 0.001) and 26.6 seconds (95% CI, 19.6-33.6 seconds; P < 0.001), respectively. It also significantly reduced stimulus dose (mean difference, -209.5 mC [95% CI, -244.9 to -174.1 mC]; P < 0.001). In addition, maximum changes in systolic blood pressure and heart rate during ECT sessions significantly increased with ketamine (mean difference, 27.2 mm Hg [95% CI, 12.0-42.4 mm Hg; P = 0.001]; 25.7 beats per minute [95% CI, 14.5-36.8 beats per minute; P < 0.001], respectively). Patients reported more headaches with ketamine ( P = 0.041). CONCLUSIONS: Our results provide evidence that ketamine as an alternative anesthetic can augment seizure durations in specific patients experiencing suboptimal seizures during an acute course of ECT. However, its use requires greater attention to circulatory management and postseizure complications.

Quantitative and calculated estimated blood loss in cesarean deliveries for twin and singleton pregnancies: a retrospective analysis.

PURPOSE: This study retrospectively assessed blood loss during cesarean deliveries for twin and singleton pregnancies using two distinct methods, quantitative estimation measured during cesarean sections and hematocrit-based calculated estimation. METHODS: We included scheduled cesarean deliveries for twin or singleton pregnancies at ≥ 34 weeks of gestation. Quantitative blood loss was recorded based on the blood volume in the graduated collector bottle and by weighing the blood-soaked textiles during cesarean sections. The blood loss was calculated using the change in hematocrit levels before and after the cesarean delivery. RESULTS: We evaluated 403 cases including 44 twins and 359 singletons. Quantitative blood loss during cesarean section was significantly higher in twin pregnancies than that in singleton pregnancies (1117 [440] vs 698 [378] mL; p < 0.001). However, no significant differences were observed in the calculated blood loss between the two groups on the day after delivery (487 mL [692 mL] vs 507 mL [522 mL]; p = 0.861). On post-delivery days 4-5, twin pregnancies were associated with a significantly higher calculated blood loss than singleton pregnancies (725 [868] mL vs 444 [565] mL, p = 0.041). Although a significant moderate correlation between quantitative and calculated blood loss was observed in singleton pregnancies (r = 0.473, p < 0.001), no significant correlation was observed between twin pregnancies (r = 0.053, p = 0.735). CONCLUSION: Quantitative blood loss measurements during cesarean section may be clinically insufficient in twin pregnancies. Incorporating blood tests and continuous assessments are warranted for enhanced blood loss evaluation, especially in twin pregnancies, owing to the risk of persistent bleeding.

Hemodynamic impact of ephedrine on hypotension during general anesthesia: a prospective cohort study on middle-aged and older patients.

BACKGROUND: Ephedrine is a mixed α- and ß-agonist vasopressor that is frequently used for the correction of hypotension during general anesthesia. ß-responsiveness has been shown to decrease with age; therefore, this study aimed to determine whether aging would reduce the pressor effect of ephedrine on hypotension during general anesthesia. METHODS: Seventy-five patients aged ≥ 45 years were included in this study, with 25 patients allocated to each of the three age groups: 45-64 years, 65-74 years, and ≥ 75 years. All patients received propofol, remifentanil, and rocuronium for the induction of general anesthesia, followed by desflurane and remifentanil. Cardiac output (CO) was estimated using esCCO technology. Ephedrine (0.1 mg/kg) was administered for the correction of hypotension. The primary and secondary outcome measures were changes in the mean arterial pressure (MAP) and CO, respectively, at 5 min after the administration of ephedrine.  RESULTS: The administration of ephedrine significantly increased MAP (p < 0.001, mean difference: 8.34 [95% confidence interval (CI), 5.95-10.75] mmHg) and CO (p < 0.001, mean difference: 7.43 [95% CI, 5.20-9.65] %) across all groups. However, analysis of variance revealed that the degree of elevation of MAP (F [2, 72] = 0.546, p = 0.581, η2 = 0.015 [95% CI, 0.000-0.089]) and CO (F [2, 72] = 2.023, p = 0.140, η2 = 0.053 [95% CI, 0.000-0.162]) did not differ significantly among the groups. Similarly, Spearman's rank correlation and multiple regression analysis revealed no significant relation between age and the changes in MAP or CO after the administration of ephedrine. CONCLUSION: The administration of ephedrine significantly increased MAP and CO; however, no significant correlation with age was observed in patients aged > 45 years. These findings suggest that ephedrine is effective for the correction of hypotension during general anesthesia, even in elderly patients. TRIAL REGISTRATION: UMIN-CTR (UMIN000045038; 02/08/2021).

Comparison of hemodynamics during induction of general anesthesia with remimazolam and target-controlled propofol in middle-aged and elderly patients: a single-center, randomized, controlled trial.

BACKGROUND: Remimazolam confers a lower risk of hypotension than propofol. However, no studies have compared the efficacy of remimazolam and propofol administered using target-controlled infusion (TCI). This study aimed to investigate hemodynamic effects of remimazolam and target-controlled propofol in middle-aged and elderly patients during the induction of anesthesia. METHODS: Forty adults aged 45-80 years with the American Society of Anesthesiologists Physical Status 1-2 were randomly assigned to remimazolam or propofol group (n = 20 each). Patients received either remimazolam (12 mg/kg/h) or propofol (3 µg/mL, TCI), along with remifentanil for inducing anesthesia. We recorded the blood pressure, heart rate (HR), and estimated continuous cardiac output (esCCO) using the pulse wave transit time. The primary outcome was the maximum change in mean arterial pressure (MAP) after induction. Secondary outcomes included changes in HR, cardiac output (CO), and stroke volume (SV). RESULTS: MAP decreased after induction of anesthesia in both groups, without significant differences between the groups (- 41.1 [16.4] mmHg and - 42.8 [10.8] mmHg in remimazolam and propofol groups, respectively; mean difference: 1.7 [95% confidence interval: - 8.2 to 4.9]; p = 0.613). Furthermore, HR, CO, and SV decreased after induction in both groups, without significant differences between the groups. Remimazolam group had significantly shorter time until loss of consciousness than propofol group (1.7 [0.7] min and 3.5 [1.7] min, respectively; p < 0.001). However, MAP, HR, CO, and SV were not significantly different between the groups despite adjusting time until loss of consciousness as a covariate. Seven (35%) and 11 (55%) patients in the remimazolam and propofol groups, respectively, experienced hypotension (MAP < 65 mmHg over 2.5 min), without significant differences between the groups (p = 0.341). CONCLUSIONS: Hemodynamics were not significantly different between remimazolam and target-controlled propofol groups during induction of anesthesia. Thus, not only the choice but also the dose and usage of anesthetics are important for hemodynamic stability while inducing anesthesia. Clinicians should monitor hypotension while inducing anesthesia with remimazolam as well as propofol. TRIAL REGISTRATION: UMIN-CTR (UMIN000045612).

The Safety and Strategies for Reinitiating Electroconvulsive Therapy After ECT-Induced Takotsubo Cardiomyopathy: A Case Report and Systematic Review.

OBJECTIVES: Takotsubo cardiomyopathy (TCM) is a life-threatening complication of electroconvulsive therapy (ECT). We report the case of a 66-year-old woman who was rechallenged with ECT after ECT-induced TCM. Moreover, we have made a systematic review to assess the safety of and strategies for reinitiating ECT after TCM. METHODS: We searched for published reports on ECT-induced TCM since 1990 in MEDLINE (PubMed), Scopus, Cochrane Library, ICHUSHI, and CiNii Research. RESULTS: A total of 24 ECT-induced TCM cases were identified. Patients who developed ECT-induced TCM were predominantly middle-aged and older women. There was no specific trend in anesthetic agents used. Seventeen (70.8%) cases developed TCM by the third session in the acute ECT course. Eight (33.3%) cases developed ECT-induced TCM despite the use of ß-blockers. Ten (41.7%) cases developed cardiogenic shock or abnormal vital signs related to cardiogenic shock. All cases recovered from TCM. Eight (33.3%) cases tried to receive ECT retrial. The duration until ECT retrial was between 3 weeks and 9 months. The most common preventive measures during ECT retrial were related to ß-blockers; however, the type, dose, and route of administration of ß-blockers varied. In all cases, ECT could be reperformed without TCM recurrence. CONCLUSIONS: Electroconvulsive therapy-induced TCM is more likely to cause cardiogenic shock than nonperioperative cases; nevertheless, it has good prognosis. Cautious reinitiation of ECT after TCM recovery is possible. Further studies are required to determine preventive measures for ECT-induced TCM.

Authorship by gender in anesthesiology journals: a retrospective cross-sectional study for Japan.

PURPOSE: Although it is important to recognize gender disparities in publishing to achieve gender diversity, women's authorship in Japan remains unclear. Therefore, this study aimed to investigate the percentage and analyze the trends of articles authored and published in anesthesiology journals by Japanese female authors. METHODS: The genders of the first and last authors affiliated with Japanese institutions were surveyed in the Journal of Anesthesia (JA) (1990, 1995, and 2000-2022) and 11 international anesthesiology journals (2010-2022). RESULTS: We included 845 and 819 original research articles from JA in the analyses of the first and last authors, respectively. The proportion of female first authors significantly increased from 41 (11.7%) out of 351 before 2009 to 119 (24.1%) out of 494 after 2010 (p < 0.001). The proportion of female last authors was 11 (3.3%) out of 335 before 2009 and 22 (4.5%) out of 484 after 2010, respectively, with no significant difference (p = 0.470). We included 624 and 572 original research articles from international anesthesiology journals in the analyses of first and last authors, respectively. Among these, there were 134 (21.5%) and 23 (4.0%) female first and last authors, respectively. These proportions in international anesthesiology journals did not significantly differ from those in JA (p = 0.334, p = 0.789, respectively). CONCLUSION: The percentage of female first authors has increased, commensurate with the percentage of female anesthesiologists. However, the percentage of female last authors has not increased and remains low in Japan.

Transition in eye gaze as a predictor of emergence from general anesthesia in children and adults: a prospective observational study.

BACKGROUND: It is useful to monitor eye movements during general anesthesia, but few studies have examined neurological finding of the eyes during emergence from general anesthesia maintained with short-acting opioids and volatile anesthetics. METHODS: Thirty children aged 1-6 years and 30 adults aged 20-79 years were enrolled. Patients received general anesthesia maintained with sevoflurane and remifentanil. The timing of three physical-behavioral responses-eye-gaze transition (the cycle from conjugate to disconjugate and back to conjugate), resumption of somatic movement (limbs or body), and resumption of respiration-were recorded until spontaneous awakening. The primary outcome measure was the timing of the physical-behavioral responses. Secondary outcome measures were the incidence of eye-gaze transition, and the bispectral index, concentration of end-tidal sevoflurane, and heart rate at the timing of eye-gaze transition. RESULTS: Eye-gaze transition was evident in 29 children (96.7%; 95% confidence interval, 82.8-99.9). After the end of surgery, eye-gaze transition was observed significantly earlier than resumption of somatic movement or respiration (472 [standard deviation 219] s, 723 [235] s, and 754 [232] s, respectively; p < 0.001). In adults, 3 cases (10%; 95% CI, 0.2-26.5) showed eye-gaze transition during emergence from anesthesia. The incidence of eye-gaze transition was significantly lower in adults than in children (p < 0.001). CONCLUSION: In children, eye-gaze transition was observed significantly earlier than other physical-behavioral responses during emergence from general anesthesia and seemed to reflect emergence from anesthesia. In contrast, observation of eye gaze was not a useful indicator of emergence from anesthesia in adults.

Impact of surgical masks on fraction of inspired oxygen during oxygen therapy depends on the type of oxygen masks and respiratory conditions: volunteer- and simulation-based studies.

PURPOSE: We investigated the impact of surgical masks (SM) during oxygen therapy using oxygen masks in volunteer- and simulation-based studies. METHODS: Fifteen volunteers wore the Hudson RCI® or Open-Face Mask® with/without an SM. The fraction of inspired oxygen concentration (FIO2), end-tidal CO2 (EtCO2), partial pressure of inspired CO2 (PICO2), and respiratory rate (RR) were measured. The oxygen flow rate increased from 0 to 10 L/min. In the simulation-based study, FIO2 was measured using a simulator that reproduced spontaneous breathing. RR was 12 or 24 bpm, and the tidal volume (Tv) was 300, 500, or 700 mL. The effect of oxygen mask fitting conditions was also examined. The primary outcome measure was FIO2 at 6 L/min. RESULTS: In the volunteer-based study, FIO2 was reduced when the SM was used with the Hudson RCI® or Open-Face Mask®. The FIO2 drop was larger with the Open-Face Mask® than with the Hudson RCI®. The RR, EtCO2, and PICO2 significantly changed with the SM, but the differences were not clinically meaningful. In the simulation-based study, the SM with the Hudson RCI® did not reduce FIO2, but the SM with the Open-Face Mask® significantly decreased FIO2 under several conditions. However, the SM with the Hudson Mask® reduced FIO2 when the fit of the mask was inadequate. With the Open-Face Mask®, lower RR and Tv resulted in larger differences in FIO2. CONCLUSIONS: The SM decreased FIO2 during oxygen therapy with oxygen masks. The impact of SM depended on the type of the oxygen mask, mask fitting, and respiratory condition.

Effects of Nicorandil Versus Nitroglycerin on Arterial Oxygenation During Two-Lung Ventilation and One-Lung Ventilation in Patients With Risk Factors for Myocardial Ischemia: A Prospective, Randomized, Double-Blind Study.

OBJECTIVES: To compare the effects of nicorandil and nitroglycerin on arterial oxygenation during two-lung ventilation (TLV) and one-lung ventilation (OLV) in patients with risk factors for myocardial ischemia. DESIGN: A prospective, randomized, double-blind study. SETTING: A tertiary care hospital. PARTICIPANTS: Fifty-six patients scheduled for elective video-assisted thoracic surgery were assigned randomly to either the nicorandil group or the nitroglycerin group. INTERVENTIONS: Patients in the nicorandil group received a bolus dose of nicorandil, 0.08 mg/kg during induction of anesthesia, followed by a continuous infusion at a rate of 0.08 mg/kg/h. Patients in the nitroglycerin group received a continuous infusion of nitroglycerin at a rate of 1 µg/kg/min from the induction of anesthesia. MEASUREMENTS AND MAIN RESULTS: Arterial blood gas analysis was performed at the following points: before induction of anesthesia; during TLV; at 5, 10, 20, and 30 minutes after the initiation of OLV. PaO2 at TLV (479.7 ± 57.1 v 408.2 ± 70.9 mmHg, p < 0.001); and at 5 minutes (344.8 ± 85.1 v 282.6 ± 85.8 mmHg, p = 0.012), 20 minutes (215.7 ± 103.0 v 158.2 ± 74.5 mmHg, p = 0.027), and 30 minutes (198.8 ± 103.5 v 147.5 ± 64.1 mmHg, p = 0.039) after OLV was significantly higher in the nicorandil group than in the nitroglycerin group. CONCLUSION: This study demonstrated that oxygenation during TLV and OLV was significantly higher in patients receiving nicorandil than in those receiving nitroglycerin.

TORSADES DE POINTES ASSOCIATED WITH TAKOTSUBO CARDIOMYOPATHY IN AN ANOREXIA NERVOSA PATIENT DURING EMERGENCE FROM GENERAL ANESTHESIA.

Takotsubo cardiomyopathy, also known as stress-induced cardiomyopathy, is a disease in which the patient exhibits transient, reversible left ventricular dysfunction that is triggered by physical or emotional stress. Prolongation of QT interval, a risk factor for arrhythmia and sudden death, has been reported to be prevalent among patients with Takotsubo cardiomyopathy and is also observed in those with severe anorexia nervosa. In this report, we describe the rare case of a 30-year-old female patient with anorexia nervosa who developed Torsades de Pointes associated with Takotsubo cardiomyopathy during emergence from general anesthesia for emergency exploratory laparotomy.

Comparison of intraoperative blood loss during spinal surgery using either remifentanil or fentanyl as an adjuvant to general anesthesia.

BACKGROUND: Remifentanil enhances intraoperative hemodynamic stability, suggesting that it may decrease intraoperative blood loss when included as an adjuvant to general anesthesia. This retrospective study compared intraoperative blood loss during spinal surgery in patients administered either remifentanil or fentanyl as an opioid adjuvant. METHODS: We reviewed clinical and surgical data from 64 consecutive laminoplasty or laminectomy patients treated at National Hospital Organization Zentsuji Hospital between April 2010 and March 2011. Patients received either remifentanil (n = 35) or fentanyl (n = 29) as an opioid analgesic during general anesthesia. In addition to intraoperative blood loss, indices of hemodynamic stability, including heart rate as well as systolic, mean, and diastolic blood pressure (BP), were compared over the entire perioperative period between remifentanil and fentanyl groups. RESULTS: The remifentanil group exhibited significantly lower intraoperative arterial BP than the fentanyl group. Intraoperative blood loss was also significantly lower in the remifentanil group (125 ± 67 mL vs. 165 ± 82 mL, P = 0.035). CONCLUSIONS: Intraoperative blood loss during spinal surgery was decreased in patients who received remifentanil as an opioid adjuvant, possibly because of lower intraoperative BP. A larger-scale prospective randomized controlled trial is warranted to confirm our results and to test whether remifentanil can decrease intraoperative blood loss during other surgical procedures.

General Anesthesia in a Patient With Neuronal Intranuclear Inclusion Disease: A Case Report.

Neuronal intranuclear inclusion disease (NIID) is a progressive neurodegenerative disease with diverse clinical manifestations, including dementia and muscle weakness. We summarize anesthetic considerations in reporting general anesthesia for a 58-year-old man with bladder dysfunction and cerebellar ataxia who was diagnosed with NIID. The patient developed postinduction hypotension relevant to autonomic neuropathy. The potential risks, such as prolonged reaction to neuromuscular blocking agent, postoperative delirium, and worsening of NIID-related symptoms, were also considered. The responsiveness to anesthetics may vary widely from case t case. As the number of NIID cases increases, a better understanding of NIID is needed.

Role of the O-linked ß-N-acetylglucosamine in the cardioprotection induced by isoflurane.

BACKGROUND: Cardiac protection by volatile anesthetic-induced preconditioning and ischemic preconditioning have similar signaling pathways. Recently, it was reported that augmentation of protein modified with O-linked ß-N-acetylglucosamine (O-GlcNAc) contributes to cardiac protection. This study investigated the role of O-GlcNAc in cardiac protection induced by anesthetic-induced preconditioning. METHODS: O-GlcNAc-modified proteins were visualized by immunoblotting. Tolerance against ischemia or reperfusion was tested in vivo (n = 8) and in vitro (n = 6). The opening of the mitochondrial permeability transition pore (mPTP) upon oxidative stress was examined in myocytes treated with calcein AM (n = 5). Coimmunoprecipitation and enzymatic labeling were performed to detect the mitochondrial protein responsible for the mPTP opening. RESULTS: Isoflurane treatment and the consequent augmentation of O-GlcNAc concentrations reduced the infarct size (26 ± 5% [mean ± SD], P < 0.001) compared with the control. The protective effect of O-GlcNAc was eliminated in the group pretreated with the O-GlcNAc transferase inhibitor alloxan (39 ± 5%, P < 0.001). Myocyte survival also showed the same result in vitro. Formation of the mPTP was abrogated in the isoflurane-treated cells (86 ± 4%, P < 0.001) compared with the control and alloxan-plus-isoflurane-treated cells (57 ± 7%, P < 0.001). Coimmunoprecipitation and enzymatic labeling studies revealed that the O-GlcNAc-modified, voltage-dependent anion channel restained the mPTP opening. CONCLUSIONS: Isoflurane induced O-GlcNAc modification of mitochondrial voltage-dependent anion channel. This modification inhibited the opening of the mPTP and conferred resistance to ischemia-reperfusion stress.

Isoflurane-induced postconditioning via mitochondrial calcium-activated potassium channels.

PURPOSE: Activation of the mitochondrial calcium-activated potassium (mKCa) channel reportedly confers resistance to myocardial ischemic stress. However, the role of the mKCa channel in postconditioning induced by volatile anesthetic remains unclear. METHODS: Male Japanese white rabbits underwent coronary artery occlusion for 30 min followed by reperfusion for 3 h. Volatile anesthetic, isoflurane, was administered at 3 min prior to reperfusion for 5 min. Rabbits were injected with the mKCa channel blocker, iberiotoxin, or the mKCa channel opener, NS1619, at 8 min prior to reperfusion. Myocardial infarct size and the area at risk (AAR) were measured at the end of the experiment. RESULTS: Isoflurane significantly reduced infarct size (23.0 ± 9.8% of the AAR, P<0.05) compared with the control (44.0 ± 9.1%). Iberiotoxin abolished the cardioprotective impact of isoflurane (43.0 ± 11.6%), while iberiotoxin alone exerted no effect on infarct size (45.0 ± 9.5%). NS1619 and isoflurane/NS1619 both significantly reduced infarct size (21.0 ± 10.3% and 19.0 ± 8.8%, respectively, P<0.05 vs control group), but isoflurane/NS1619 showed no additional benefits compared with isoflurane alone. CONCLUSION: These results indicate that activation of the mKCa channel contribute isoflurane-induced postconditioning.

Effects of a novel method of anesthesia combining propofol and volatile anesthesia on the incidence of postoperative nausea and vomiting in patients undergoing laparoscopic gynecological surgery.

BACKGROUND: We investigated the effects of a novel method of anesthesia combining propofol and volatile anesthesia on the incidence of postoperative nausea and vomiting in patients undergoing laparoscopic gynecological surgery. METHODS: Patients were randomly divided into three groups: those maintained with sevoflurane (Group S, n=42), propofol (Group P, n=42), or combined propofol and sevoflurane (Group PS, n=42). We assessed complete response (no postoperative nausea and vomiting and no rescue antiemetic use), incidence of nausea and vomiting, nausea severity score, vomiting frequency, rescue antiemetic use, and postoperative pain at 2 and 24h after surgery. RESULTS: The number of patients who exhibited a complete response was greater in Groups P and PS than in Group S at 0-2h (74%, 76% and 43%, respectively, p=0.001) and 0-24h (71%, 76% and 38%, respectively, p<0.0005). The incidence of nausea at 0-2h (Group S=57%, Group P=26% and Group PS=21%, p=0.001) and 0-24h (Group S=62%, Group P=29% and Group PS=21%, p<0.0005) was also significantly different among groups. However, there were no significant differences among groups in the incidence or frequency of vomiting or rescue antiemetic use at 0-24h. CONCLUSION: Combined propofol and volatile anesthesia during laparoscopic gynecological surgery effectively decreases the incidence of postoperative nausea. We term this novel method of anesthesia "combined intravenous-volatile anesthesia (CIVA)".

[Effects of a novel method of anesthesia combining propofol and volatile anesthesia on the incidence of postoperative nausea and vomiting in patients undergoing laparoscopic gynecological surgery]. / Efeitos de um novo método de anestesia combinando propofol e anestesia volátil sobre a incidência de náusea e vômito no pós-operatório em pacientes submetidas à laparoscopia ginecológica.

BACKGROUND: We investigated the effects of a novel method of anesthesia combining propofol and volatile anesthesia on the incidence of postoperative nausea and vomiting in patients undergoing laparoscopic gynecological surgery. METHODS: Patients were randomly divided into three groups: those maintained with sevoflurane (Group S; n = 42), propofol (Group P; n = 42), or combined propofol and sevoflurane (Group PS; n = 42). We assessed complete response (no postoperative nausea and vomiting and no rescue antiemetic use), incidence of nausea and vomiting, nausea severity score, vomiting frequency, rescue antiemetic use, and postoperative pain at 2 and 24h after surgery. RESULTS: The number of patients who exhibited a complete response was greater in Groups P and PS than in Group S at 0-2h (74%; 76% and 43%; respectively, p = 0.001) and 0-24h (71%; 76%, and 38%; respectively, p < 0.0005). The incidence of nausea at 0-2h (Group S = 57%; Group P = 26% and Group PS = 21%; p = 0.001) and 0-24h (Group S = 62%; Group P = 29% and Group PS = 21%; p < 0.0005) was also significantly different among groups. However, there were no significant differences among groups in the incidence or frequency of vomiting or rescue antiemetic use at 0-24h. CONCLUSION: Combined propofol and volatile anesthesia during laparoscopic gynecological surgery effectively decreases the incidence of postoperative nausea.

Differential effects of propofol and isoflurane on glucose utilization and insulin secretion.

AIMS: Volatile anesthetics, such as isoflurane, reverse glucose-induced inhibition of pancreatic adenosine triphosphate-sensitive potassium (K(ATP)) channel activity, resulting in reduced insulin secretion and impaired glucose tolerance. No previous studies have investigated the effects of intravenous anesthetics, such as propofol, on pancreatic K(ATP) channels. We investigated the cellular mechanisms underlying the effects of isoflurane and propofol on pancreatic K(ATP) channels and insulin secretion. MAIN METHODS: Intravenous glucose tolerance tests (IVGTT) were performed on male rabbits. Pancreatic islets were isolated from male rats and used for a perifusion study, measurement of intracellular ATP concentration ([ATP](i)), and patch clamp experiments. KEY FINDINGS: Glucose stimulus significantly increased insulin secretion during propofol anesthesia, but not isoflurane anesthesia, in IVGTT study. In perifusion experiments, both islets exposed to propofol and control islets not exposed to anesthetic had a biphasic insulin secretory response to a high dose of glucose. However, isoflurane markedly inhibited glucose-induced insulin secretion. In a patch clamp study, the relationship between ATP concentration and channel activity could be fitted by the Hill equation with a half-maximal inhibition of 22.4, 15.8, and 218.8 µM in the absence of anesthetic, and with propofol, and isoflurane, respectively. [ATP](i) and single K(ATP) channel conductance did not differ in islets exposed to isoflurane or propofol. SIGNIFICANCE: Our results indicate that isoflurane, but not propofol, decreases the ATP sensitivity of K(ATP) channels and impairs glucose-stimulated insulin release. These differential actions of isoflurane and propofol on ATP sensitivity may explain the differential effects of isoflurane and propofol on insulin release.