Comparison of hypotension incidence between remimazolam and propofol in patients with hypertension undergoing neurosurgery: prospective, randomized, single-blind trial.

BACKGROUND: Remimazolam, a newer benzodiazepine that targets the GABAA receptor, is thought to allow more stable blood pressure management during anesthesia induction. In contrast, propofol is associated with vasodilatory effects and an increased risk of hypotension, particularly in patients with comorbidities. This study aimed to identify medications that can maintain stable vital signs throughout the induction phase. METHODS: We conducted a single-center, two-group, randomized controlled trial to investigate and compare the incidence of hypotension between remimazolam- and propofol-based total intravenous anesthesia (TIVA). We selected patients aged between 19 and 75 years scheduled for neurosurgery under general anesthesia, who were classified as American Society of Anesthesiologists Physical Status I-III and had a history of hypertension. RESULTS: We included 94 patients in the final analysis. The incidence of hypotension was higher in the propofol group (91.3%) than in the remimazolam group (85.4%; P = 0.057). There was no significant difference in the incidence of hypotension among the various antihypertensive medications despite the majority of patients being on multiple medications. In comparison with the propofol group, the remimazolam group demonstrated a higher heart rate immediately after intubation. CONCLUSIONS: Our study indicated that the hypotension incidence of remimazolam-based TIVA was comparable to that of propofol-based TIVA throughout the induction phase of EEG-guided anesthesia. Both remimazolam and propofol may be equally suitable for general anesthesia in patients undergoing neurosurgery. TRIAL REGISTRATION: Clinicaltrials.gov (NCT05164146).

Comparison of the effects of inhalational and total intravenous anesthesia on quality of recovery in patients undergoing endoscopic transsphenoidal pituitary surgery: a randomized controlled trial.

Background: Endoscopic transsphenoidal pituitary surgery has shown promising results. However, fast and high-quality recovery after this procedure remains a challenge for neuroanesthesiologists. This study aimed to compare the quality of recovery after transsphenoidal pituitary surgery between patients who received inhalational anesthesia with sevoflurane and patients who received propofol-based total intravenous anesthesia (TIVA). Methods: Eighty-two patients undergoing transsphenoidal pituitary surgery were randomized to receive either sevoflurane inhalation with manual infusion of remifentanil (sevoflurane group) or effect-site target-controlled infusion of propofol and remifentanil (TIVA group). The primary outcome was the 40-item Quality of Recovery (QoR-40) score on postoperative day 1. The QoR-40 questionnaire was completed by patients the day before surgery and on postoperative days 1 and 2. Emergence agitation and recovery characteristics were also assessed. Results: There were no significant differences between the groups in the global QoR-40 scores on both postoperative days 1 and 2 (difference -8.7, 95% CI -18.0 to 0.7, and P = 0.204; -3.6, 95% CI -13.0 to 5.8, and P > 0.999, respectively). The time to verbal response and time to extubation were significantly shorter in the sevoflurane group than in the TIVA group (P < 0.001 and P < 0.001, respectively). However, the incidence of emergence agitation was lower in the TIVA group than in the sevoflurane group (P < 0.001). Conclusions: Both inhalational anesthesia with sevoflurane and propofol-based TIVA were appropriate anesthetic techniques for patients undergoing endoscopic transsphenoidal pituitary surgery in terms of the quality of recovery up to 2 days postoperatively. Rapid emergence was observed in the sevoflurane group, while smooth emergence was observed in the TIVA group.

Preoperative cephalhematoma size measured with computed tomography predicts intraoperative bleeding in pediatric patients undergoing cranioplasty.

BACKGROUND: Cranioplasty for the treatment of cephalhematomas in small infants with limited blood volume is challenging because of massive bleeding. This study aimed to elucidate the correlation between cephalhematoma size and intraoperative blood loss and identify criteria that can predict large intraoperative blood loss. METHODS: We reviewed the medical records of 120 pediatric patients aged less than 24 months who underwent cranioplasty for treatment of a cephalhematoma. The cephalhematoma sizes in preoperative brain computed tomography (CT) were measured using ImageJ. RESULTS: Pearson correlation showed that the cephalhematoma size in the pre-operative brain CT was weakly correlated with intraoperative blood loss (Pearson coefficient = 0.192, P = 0.037). In a multivariable logistic regression analysis, a cephalhematoma size greater than 113.5 cm3 was found to be a risk factor for large blood loss. The area under the curve in the receiver operating characteristic plot of the multivariable model was 0.714 (0.619-0.809). CONCLUSIONS: A cephalhematoma size cutoff value of 113.5 cm3, as measured in the preoperative CT imaging, can predict intraoperative blood loss exceeding 30% of the total body blood volume. The establishment of a transfusion strategy prior to surgery based on cephalhematoma size could be useful in pediatric cranioplasty.

Bleeding properties according to surgical sites during pediatric craniotomy: a retrospective study comparing the two stages of epilepsy surgery.

BACKGROUND: During pediatric epilepsy surgery, due to low circulating blood volume, intraoperative bleeding can result in significant hemodynamic instability, thereby requiring meticulous hemodynamic and transfusion strategies. Knowing the source of bleeding during the procedure would allow medical staff to better prepare the perioperative protocols for these patients. We compared intraoperative bleeding between the first (involving skin to meninges) and second (involving brain parenchyma) stages of epilepsy surgery to investigate the differences between various anatomical sites. METHODS: We reviewed the electronic medical records of 102 pediatric patients < 14 years old who underwent two-stage epilepsy surgeries during January 2012-December 2016. Invasive subdural grids were placed via craniotomy during Stage 1 and the epileptogenic zone was removed during Stage 2 of the surgery. We compared the volume of intraoperative bleeding between these two surgeries and identified variables associated with bleeding using multivariate regression analysis. RESULTS: Both surgeries resulted in similar intraoperative bleeding (24 vs. 26 ml/kg, P = 0.835), but Stage 2 required greater volumes of blood transfusion than Stage 1 (18.4 vs. 14.8 ml/kg, P = 0.011). Massive bleeding was associated with patients < 7 years of age in Stage 1 and weighing < 18 kg in Stage 2. CONCLUSIONS: The volume of intraoperative bleeding was similar between the two stages of pediatric epilepsy surgery and was large enough to require blood transfusions. Thus, blood loss during pediatric epilepsy surgery occurred at both anatomic sites. This indicates the necessity of early preparation for blood transfusion in both stages of pediatric epilepsy surgery.

Sleep disturbance and delirium in patients with acromegaly in the early postoperative period after transsphenoidal pituitary surgery.

Sleep disturbance is a common comorbidity among patients with acromegaly [patients with growth hormone (GH)-secreting tumor] due to somatotropic axis change and sleep apnea. However, no previous studies exist concerning sleep disturbance and delirium in the early postoperative period in patients with acromegaly undergoing transsphenoidal tumor surgery. Herein, we aimed to compare the incidence of postoperative sleep disturbance and delirium in the early postoperative period between patients with GH-secreting and nonfunctioning pituitary tumors.We retrospectively reviewed the medical records of 1286 patients (969 with nonfunctioning and 317 with GH-secreting tumors) without history of psychological disease and sedative or antipsychotic use. We examined the use of antipsychotics/sedatives and findings of psychology consultation within the first postoperative week. Only patients with sleep disturbance noted in medical records were considered to have postoperative sleep disturbance. Patients with an Intensive Care Delirium Screening Checklist score of 4 or more were considered to have postoperative delirium.The incidence of postoperative sleep disturbance was higher in the GH-secreting group than in the nonfunctioning tumor group (2/969 [0.2%] vs 6/317 [1.9%]; P = .004; odds ratio = 9.328 [95% confidence interval, 1.873-46.452]). Univariable regression analysis showed that only diagnosis (GH-secreting tumor or nonfunctioning tumor) was a risk factor for sleep disturbance, and not sex, age, body mass index, American Society of Anesthesiologists physical status score, surgery duration, anesthesia duration, anesthesia type, tumor size, cavernous sinus invasion, or bleeding. The incidence of postoperative delirium was comparable between the 2 groups (6/969 [0.6%] vs 0/317 [0%]; P = .346).Patients with acromegaly showed increased incidence of sleep disturbance than those with nonfunctioning tumors in the early postoperative period after transsphenoidal tumor surgery. A prospective study evaluating sleep quality in patients with GH-secreting tumors in the early postoperative period could be conducted based on our findings.

The radiation environment of anaesthesiologists in the endoscopic retrograde cholangiopancreatography room.

Anaesthesiologists are increasingly involved in nonoperating room anaesthesia (NORA) for fluoroscopic procedures. However, the radiation exposure of medical staff differs among NORA settings. Therefore, we aimed to investigate the radiation environment generated by fluoroscopic endoscopic retrograde cholangiopancreatography (ERCP) and the radiation exposure of anaesthesiologists. The dose area product (DAP), radiation entrance dose (RED), and fluoroscopy time (FT) according to the procedures and monthly cumulative radiation exposure were analysed at two sites (neck and wrist) from 363 procedures in 316 patients performed within 3 months. The total RED and DAP were 43643.1 mGy and 13681.1 Gy cm2, respectively. DAP and RED (r = 0.924) were strongly correlated and DAP and FT (r = 0.701) and RED and FT (r = 0.749) were moderately correlated. The radiation environment per procedure varied widely, DAP and RED per FT were the highest during stent insertion with esophagogastroduodenoscopy. Monthly cumulative deep dose equivalents at the wrist and neck ranged between 0.31-1.27 mSv and 0.33-0.59 mSv, respectively, but they were related to jaw thrust manipulation (r = 0.997, P = 0.047) and not to the radiation environment. The anaesthesiologists may be exposed to high dose of radiation in the ERCP room, which depends on the volume of procedures performed and perhaps the anaesthesiologists' practice patterns.

Haemodynamic changes and incisional bleeding after scalp infiltration of dexmedetomidine with lidocaine in neurosurgical patients.

BACKGROUND: The purpose of this randomised controlled study is to compare the haemodynamic changes and the degree of incisional bleeding after scalp infiltration of lidocaine and dexmedetomidine versus lidocaine and epinephrine for patients with hemi-facial spasm undergoing microvascular decompression. METHODS: Fifty-two patients were injected with 5 mL of 1% lidocaine with either dexmedetomidine (2 µg/mL) or epinephrine (1:100,000 dilution) to reduce scalp bleeding. Mean blood pressure and heart rate were recorded every minute for 15 minutes after scalp infiltration. The primary outcome was the incidence of predefined hypotension, which was treated with administration of 4 mg ephedrine as often as needed. The number of administrations and total amount of ephedrine administered were also recorded as a measure of the severity of hypotension. The neurosurgeon scored incisional bleeding by numeric rating scale from 0 (worst) to 10 (best). RESULTS: The incidence of hypotension (68% vs. 34.8%, P = 0.02) and the frequency (P = 0.02) and total dose (P = 0.03) of ephedrine administered were lower in the dexmedetomidine group than in the epinephrine group. In addition, there was no difference in mean blood pressure between the two groups but heart rates were lower in the dexmedetomidine group (P = 0.01). Incisional site bleeding was better with epinephrine (median [interquartile range] of the numeric rating Score: 6 [4] in the dexmedetomidine group and 8 [2] in the epinephrine group; P < 0.001). CONCLUSION: The dexmedetomidine-lidocaine combination may be recommended as a substitute for epinephrine-lidocaine for scalp infiltration in neurosurgical patients, especially neurologically compromised patients.

Accidental intracerebral injection and seizure during scalp nerve blocks for awake craniotomy in a previously craniotomized patient -a case report.

A 34-year-old man who previously underwent a craniotomy due to oligodendroglioma was admitted with a diagnosis of recurrent brain tumor. An awake craniotomy was planned. Approximately 15 minutes after completing the scalp nerve block, his upper torso suddenly moved and trembled for 10 seconds, suggesting a generalized clonic seizure. He recovered gradually and fully in 55 minutes without any neurological sequelae. The emergency computed tomography scan revealed a localized fluid collection and small intracerebral hemorrhage nearby in the temporoparietal cortex beneath the skull defect. He underwent surgery under general anesthesia at 8 hours after the seizure and was discharged from the hospital after 10 days. This report documents the first case of generalized seizure that was caused by the accidental intracerebral injection of local anesthetics. Although the patient recovered completely, the clinical implications regarding the scalp infiltration technique in a patient with skull defects are discussed.

Comparison of ramosetron and ondansetron for the treatment of established postoperative nausea and vomiting after laparoscopic surgery: a prospective, randomized, double-blinded multicenter trial.

BACKGROUND: Postoperative nausea and vomiting (PONV) is a common complication after surgery, which increases physical and psychological discomfort and delays recovery. The aim of this study was to test the hypothesis that ramosetron is comparable to ondansetron for the treatment of established PONV after laparoscopic surgery using a prospective, randomized, double-blinded, noninferiority study. METHODS: Patients who had at least two risk factors of PONV and underwent laparoscopic surgery under general anesthesia were assessed for eligibility. Patients who developed PONV within the first 2 h after anesthesia received ondansetron (4 mg) or ramosetron (0.3 mg) intravenously in a randomized double-blind manner. Patients were then observed for 24 h after drug administration. The incidence of nausea and vomiting, severity of nausea, rescue antiemetic necessity, and adverse effects at 0-2 or 2-24 h after drug administration was evaluated. The primary endpoint was the rate of patients exhibiting a complete response, defined as no emesis and no further rescue antiemetic medication for 24 h after drug administration. RESULTS: Among the 583 patients, 210 (36.0%) developed PONV and were randomized to either the ondansetron (n=105) or ramosetron (n=105) group. Patient's characteristics were similar between the groups. The complete response rate was 44.1% in the ondansetron group and 52.9% in the ramosetron group after 24 h of initial antiemetic administration. The incidence of adverse events was not different between the groups. CONCLUSION: We found evidence to support the noninferiority of ramosetron (0.3 mg) compared to ondansetron (4 mg) for the treatment of established PONV in moderate to high-risk patients undergoing laparoscopic surgery.

Comparison of Dexmedetomidine and Remifentanil on Airway Reflex and Hemodynamic Changes during Recovery after Craniotomy.

PURPOSE: During emergence from anesthesia for a craniotomy, maintenance of hemodynamic stability and prompt evaluation of neurological status is mandatory. The aim of this prospective, randomized, double-blind study was to compare the effects of dexmedetomidine and remifentanil on airway reflex and hemodynamic change in patients undergoing craniotomy. MATERIALS AND METHODS: Seventy-four patients undergoing clipping of unruptured cerebral aneurysm were recruited. In the dexmedetomidine group, patients were administered dexmedetomidine (0.5 µg/kg) for 5 minutes, while the patients of the remifentanil group were administered remifentanil with an effect site concentration of 1.5 ng/mL until endotracheal extubation. The incidence and severity of cough and hemodynamic variables were measured during the recovery period. Hemodynamic variables, respiration rate, and sedation scale were measured after extubation and in the post-anesthetic care unit (PACU). RESULTS: The incidence of grade 2 and 3 cough at the point of extubation was 62.5% in the dexmedetomidine group and 53.1% in the remifentanil group (p=0.39). Mean arterial pressure (p=0.01) at admission to the PACU and heart rate (p=0.04 and 0.01, respectively) at admission and at 10 minutes in the PACU were significantly lower in the dexmedetomidine group. Respiration rate was significantly lower in the remifentanil group at 2 minutes (p<0.01) and 5 minutes (p<0.01) after extubation. CONCLUSION: We concluded that a single bolus of dexmedetomidine (0.5 µg/kg) and remifentanil infusion have equal effectiveness in attenuating coughing and hemodynamic changes in patients undergoing cerebral aneurysm clipping; however, dexmedetomidine leads to better preservation of respiration.

Comparison of the antiemetic effect of ramosetron with ondansetron in patients undergoing microvascular decompression with retromastoid craniotomy: a preliminary report.

BACKGROUND: Microvascular decompression with retromastoid craniotomy carries an especially high risk of postoperative nausea and vomiting. In this study, we compare the antiemetic efficacy of ramosetron and ondansetron in patients undergoing microvascular decompression with retromastoid craniotomy. METHODS: Using balanced anesthesia with sevoflurane and remifentanil infusion, ondansetron 8 mg (group O, n = 31) or ramosetron 0.3 mg (group R, n = 31) was administered at the dural closure. The incidence and severity of postoperative nausea and vomiting, required rescue medications and the incidence of side effects were measured at post-anesthetic care unit, 6, 24 and 48 hours postoperatively. Independent t-tests and the chi-square test or Fisher's exact test were used for statistical analyses. RESULTS: There were no differences in the demographic data between groups, except for a slightly longer anesthetic duration of group R (P = 0.01). The overall postoperative 48 hour incidences of nausea and vomiting were 93.6 and 61.3% (group O), and 87.1 and 51.6% (group R), respectively. Patients in group R showed a less severe degree of nausea (P = 0.02) and a lower incidence of dizziness (P = 0.04) between 6 and 24 hours. CONCLUSIONS: The preventive efficacy of ramosetron when used for postoperative nausea and vomiting was similar to that of ondansetron up to 48 hours after surgery in patients undergoing microvascular decompression with retromastoid craniotomy. A larger randomized controlled trial is needed to confirm our findings.

Comparison of the efficacy and safety of sedation between dexmedetomidine-remifentanil and propofol-remifentanil during endoscopic submucosal dissection.

AIM: To compare the efficacy and safety of sedation protocols for endoscopic submucosal dissection (ESD) between dexmedetomidine-remifentanil and propofol-remifentanil. METHODS: Fifty-nine patients scheduled for ESD were randomly allocated into a dexmedetomidine-remifentanil (DR) group or a propofol-remifentanil (PR) group. To control patient anxiety, dexmedetomidine or propofol was infused to maintain a score of 4-5 on the Modified Observer's Assessment of Alertness/Sedation scale. Remifentanil was infused continuously at a rate of 6 µg/kg per hour in both groups. The ease of advancing the scope into the throat, gastric motility grading, and satisfaction of the endoscopist and patient were assessed. Hemodynamic variables and hypoxemic events were compared to evaluate patient safety. RESULTS: Demographic data were comparable between the groups. The hemodynamic variables and pulse oximetry values were stable during the procedure in both groups despite a lower heart rate in the DR group. No oxygen desaturation events occurred in either group. Although advancing the scope into the throat was easier in the PR group ("very easy" 24.1% vs 56.7%, P = 0.010), gastric motility was more suppressed in the DR group ("no + mild" 96.6% vs 73.3%, P = 0.013). The endoscopists felt that the procedure was more favorable in the DR group ("very good + good" 100% vs 86.7%, P = 0.042), whereas patient satisfaction scores were comparable between the groups. En bloc resection was performed 100% of the time in both groups, and the complete resection rate was 94.4% in the DR group and 100% in the PR group (P = 0.477). CONCLUSION: The efficacy and safety of dexmedetomidine and remifentanil were comparable to propofol and remifentanil during ESD. However, the endoscopists favored dexmedetomidine perhaps due to lower gastric motility.

Determination of EC95 of remifentanil for smooth emergence from propofol anesthesia in patients undergoing transsphenoidal surgery.

BACKGROUND: In patients undergoing pituitary surgery using a transsphenoidal approach, anesthesia emergence should be smooth with minimal coughing. Recent studies demonstrated that a target-controlled infusion of remifentanil effectively suppresses coughing induced by the endotracheal tube. We investigated the EC95 of remifentanil for smooth emergence without coughing from propofol anesthesia in patients undergoing transsphenoidal hypophysectomy. MATERIALS AND METHODS: A total of 41 patients undergoing transsphenoidal hypophysectomy, aged 20 to 65 years, with an ASA physical status of I or II, were enrolled. For all participants, anesthesia was induced and maintained with a target-controlled infusion of remifentanil and propofol using predicted effect-site concentration (Ce). A biased coin design up-and-down sequential allocation and isotonic regression method were used to determine the remifentanil EC95 to prevent emergence coughing. In addition, we observed recovery profiles after anesthesia. RESULTS: According to the study design, 19 patients received remifentanil 2.6 ng/mL Ce and 22 patients received a lower Ce, ranging from 1.0 to 2.2 ng/mL. The EC95 of remifentanil to prevent coughing was estimated as 2.51 ng/mL (95% confidence interval, 2.28-2.57 ng/mL). Despite the exclusion of 1 case because of delayed emergence, 17 of 18 patients receiving 2.6 ng/mL of remifentanil had bradypnea (<10 breaths/min) until 3 minutes after extubation. However, end-tidal carbon dioxide was maintained below 55 mm Hg during anesthetic emergence and respiratory rate recovered within 20 minutes of admission to the postanesthetic care unit. CONCLUSIONS: The EC95 of remifentanil for smooth emergence from anesthesia was 2.51 ng/mL after transsphenoidal hypophysectomy.

Remote cerebellar hemorrhage after unruptured cerebral aneurysm surgery: two cases report.

Remote cerebellar hemorrhage (RCH) occurring distant to the site of original surgery, such as supratentorial or spinal surgery, is rare but potentially fatal. Because the pathophysiology of RCH is thought to be excessive cerebrospinal fluid drainage during the perioperative periods, its diagnosis usually depends on the occurrence of unexpected neurologic disturbances and/or postoperative brain computerized tomography imaging. Because of its rarity, RCH-associated neurologic disturbances such as delayed awakening or nausea and vomiting may often be misdiagnosed as the effects of residual anesthetics or the effect of postoperative analgesic agents unless radiologic images are taken. Treatment for RCH ranges from conservative treatment to decompressive craniectomy, with prognoses ranging from complete resolution to fatality. Here, we report two cases of RCH after surgical clipping of an unruptured cerebral aneurysm of the anterior communicating artery and review anesthetic considerations.

A prospective, randomized, double-blind, and multicenter trial of prophylactic effects of ramosetronon postoperative nausea and vomiting (PONV) after craniotomy: comparison with ondansetron.

BACKGROUND: Craniotomy patients have a high incidence of postoperative nausea and vomiting (PONV). This prospective, randomized, double-blind, multi-center study was performed to evaluate the efficacy of prophylactic ramosetron in preventing PONV compared with ondansetron after elective craniotomy in adult patients. METHODS: A total of 160 American Society of Anesthesiologists physical status I-II patients aged 19-65 years who were scheduled to undergo elective craniotomy for various intracranial lesions were enrolled in this study. All patients received total intravenous anesthesia (TIVA) with propofol and remifentanil. Patients were randomly allocated into three groups to receive ondansetron (4 mg; group A, n  =  55), ondansetron (8 mg; group B, n  =  54), or ramosetron (0.3 mg; group C, n  =  51) intravenously at the time of dural closure. The incidence of PONV, the need for rescue antiemetics, pain score, patient-controlled analgesia (PCA) consumption, and adverse events were recorded 48 h postoperatively. RESULTS: Among the initial 160 patients, 127 completed the study and were included in the final analysis. The incidences of PONV were lower (nausea, 14% vs. 59% and 41%, respectively; P  <  0.001; vomiting, P  =  0.048) and the incidence of complete response was higher (83% vs. 37% and 59%, respectively; P  <  0.001) in group C than in groups A and B at 48 h postoperatively. There were no significant differences in the incidence of PONV or need for rescue antiemetics 0-2 h postoperatively, but significant differences were observed in the incidence of PONV and complete response among the three groups 2-48 h postoperatively. No statistically significant intergroup differences were observed in postoperative pain, PCA consumption, or adverse events. CONCLUSION: Intravenous administration of ramosetron at 0.3 mg reduced the incidence of PONV and rescue antiemetic requirement in craniotomy patients. Ramosetron at 0.3 mg was more effective than ondansetron at 4 or 8 mg for preventing PONV in adult craniotomy patients. TRIAL REGISTRATION: CLINICAL RESEARCH INFORMATION SERVICE (CRIS) IDENTIFIER: KCT0000320. Registered 9 January 2012.

Dexmedetomidine for rigid bronchoscopy in an infant with tracheal web after ventricular septal defect patch repair.

We report herein successful rigid bronchoscopy with preserved spontaneous breathing of a 54-day-old infant with tracheal web associated with previous ventricular septal defect (VSD) repair. We considered the use of dexmedetomidine in conjunction with intermittent ketamine from the following three clinical aspects. First, this infant was suffering from respiratory distress with chest retraction, the cause of which was not revealed by a computerized scan of the neck and chest. Second, the patient was scheduled for rigid bronchoscopy, which is accompanied by brief but strong stimulation. Third, this infant underwent congenital VSD heart repair approximately 1 month earlier.

Effect of a single dose of esmolol on the bispectral index to endotracheal intubation during desflurane anesthesia.

BACKGROUND: In this prospective, randomized, double-blind, placebo-controlled trial, we investigated the effect of a single dose of esmolol on the bispectral index (BIS) to endotracheal intubation during desflurane anesthesia. METHODS: After induction of anesthesia, 60 patients were mask-ventilated with desflurane (end-tidal 1 minimum alveolar concentration) for 5 min and then received either normal saline, esmolol 0.5 or 1 mg/kg, 1 min prior to intubation (control, esmolol-0.5 and esmolol-1 groups, n = 20/group). BIS, mean arterial pressure, and heart rate were measured prior to anesthesia induction and esmolol administration, immediately preceding intubation (time point 0), and every minute for 5 min after intubation (time point 1 to 5). At time point 0, 1 and 5, 5 ml of arterial blood was taken to measure plasma concentrations of norepinephrine and epinephrine. RESULTS: BIS increased significantly at 1 min after intubation when compared with pre-intubation values in all groups. Both mean arterial pressure and heart rate increased significantly 1 min after intubation when compared with preintubation values for all groups. Plasma epinephrine concentrations did not increase significantly after tracheal intubation in any of the groups. Norepinephrine increased at 1 min after intubation when compared with the preintubation values in the esmolol groups (P < 0.05). CONCLUSIONS: A single bolus of esmolol was unable to blunt the increase in BIS to endotracheal intubation during desflurane anesthesia.

Small dose of propofol combined with dexamethasone for postoperative vomiting in pediatric Moyamoya disease patients: a prospective, observer-blinded, randomized controlled study.

BACKGROUND: For effective postoperative antiemetic management in pediatric moyamoya disease patients receiving fentanyl based postoperative analgesia, a multimodal approach has been recommended. The uncertain efficacy of ondansetron for pediatric neurosurgical patients or the possible antiemetic effect of small dose of propofol motivated us to evaluate the preventive effect of a subhypnotic dose of propofol combined with dexamethasone on postoperative vomiting (POV), especially during immediate postoperative periods. METHODS: In a prospective observer-blind randomized controlled study, we compared dexamethasone 0.15 mg/kg alone (Group D) with dexamethasone combined with propofol of 0.5 mg/kg (Group DP) in 60 pediatric patients, aged 4-17 years, who underwent indirect bypass surgery and received fentanyl-based postoperative analgesia. Occurrence of vomiting and pain score (Wong-Baker facial score) and requirement of rescue analgesic and antiemetic were continually measured (0-2, 2-6, 6-12 and 12-24 postoperative hours). For statistical analysis, in addition to the Fisher's exact test, a generalized linear mixed model (GLMM) and the linear mixed model (LMM) for repeated measures were used for vomiting and pain scores, respectively. RESULTS: There was no statistical significance of POV incidence, requirement of rescue analgesic and pain score between the two groups at any measured intervals. The incidence of POV was 53.3% during 24 hours in both groups, and was especially 6.7% and 13.3% (P = 0.671) during 0-2 hr and 16.7% and 23.3% (P = 0.748) during 2-6 hr in group D and group DP, respectively. CONCLUSIONS: A small dose of propofol combined with dexamethasone appears ineffective to preventing POV in pediatric moyamoya patients receiving continuous fentanyl infusion.

Effects of beach-chair position and induced hypotension on cerebral oxygen saturation in patients undergoing arthroscopic shoulder surgery.

PURPOSE: We investigated the effects of the beach-chair position and induced hypotension on regional cerebral oxygen saturation (rSO(2)) in patients undergoing arthroscopic shoulder surgery by using near-infrared spectroscopy. METHODS: Twenty-eight patients scheduled for arthroscopic shoulder surgery were enrolled prospectively. After induction of anesthesia, mechanical ventilation was controlled to maintain Paco(2) at 35 to 40 mm Hg. Anesthesia was maintained with sevoflurane and remifentanil. After radial artery cannulation, mean arterial pressure (MAP) was measured at the external auditory meatus level and maintained between 60 and 65 mm Hg. The rSO(2) was measured by use of near-infrared spectroscopy. MAP and rSO(2) were recorded at the following times: before induction (T(0)), immediately after induction (T(1) [baseline]), after beach-chair position (T(2)), immediately after induced hypotension (T(3)), 1 hour after induced hypotension (T(4)), and after supine position at the end of surgery (T(5)). Cerebral desaturation was defined as a reduction in rSO(2) to less than 80% of baseline value for 15 seconds or greater. RESULTS: A total of 27 patients were evaluated until the end of this study. The MAP at T(2) was significantly lower than that at T(1). The MAP values at T(3) and T(4) were significantly lower than those at T(1) and T(2). The rSO(2) at T(2) was significantly lower than that at T(1). Unlike the pattern of change in the MAP, there was no additional decrease in rSO(2) at T(3) and T(4). There were 2 patients who had an episode of cerebral desaturation. CONCLUSIONS: The beach-chair position combined with induced hypotension significantly decreases rSO(2) in patients undergoing shoulder arthroscopic surgery under general anesthesia. LEVEL OF EVIDENCE: Level IV, study of nonconsecutive patients without consistently applied reference gold standard.