Effect of converting from propofol to remimazolam with flumazenil reversal on recovery from anesthesia in outpatients with mental disabilities: a randomized controlled trial.

BACKGROUND: General anesthesia is often necessary for dental treatment of outpatients with mental disabilities. Rapid recovery and effective management of postoperative nausea and vomiting (PONV) are critical for outpatients. This study aimed to investigate the effect of transitioning from propofol to remimazolam with flumazenil reversal administered toward the end of surgery during propofol-based total intravenous anesthesia (TIVA) on recovery. METHODS: Adults with mental disabilities scheduled to undergo dental treatment were randomly assigned to receive either propofol-based TIVA (Group P) or propofol-remimazolam-based TIVA with flumazenil reversal (Group PR). Propofol was replaced with remimazolam 1 h before the end of surgery in Group PR; moreover, 0.5 mg of flumazenil was administered after the neuromuscular blockade reversal agent. The primary outcome was the duration of stay in the post-anesthesia care unit (PACU). The secondary outcomes included time to eye-opening, time to extubation, occurrence of PONV, and quality of recovery. RESULTS: Fifty-four patients were included in this study. The duration of stay in the PACU in Group PR was significantly shorter than that in Group P (mean difference, 8.7 min; confidence interval [95% CI], 3.3-14.2; P = 0.002). Group PR exhibited a shorter time to eye opening (mean difference, 5.4 min; 95% CI, 3.3-8.1; P < 0.001) and time to extubation (mean difference, 5.5 min; 95% CI, 3.6-7.9; P < 0.001) than Group P. Neither group required the administration of rescue analgesics, and the incidence of PONV was not reported. CONCLUSIONS: Transitioning from propofol to remimazolam 1 h before the end of surgery followed by flumazenil reversal reduced the duration of stay in the PACU and the time to eye opening and extubation without affecting the incidence of PONV and quality of recovery. TRIAL REGISTRATION NUMBER: Clinical Research Information Service (KCT0007794), Clinical trial first registration date: 12/10/2022.

The utilization of video laryngoscopy in nasotracheal intubation for oral and maxillofacial surgical procedures: a narrative review.

The video laryngoscope is a novel instrument for intubation that enables indirect visualization of the upper airway. It is recognized for its ability to enhance Cormack-Lehane grades in the management of difficult airways. Notably, video laryngoscopy is associated with equal or higher rates of intubation success within a shorter time frame than direct laryngoscopy. Video laryngoscopy facilitates faster and easier visualization of the glottis and reduces the need for Magill forceps, thereby shortening the intubation time. Despite the advanced glottic visualization afforded by video laryngoscopy, nasotracheal tube insertion and advancement occasionally fail. This is particularly evident during nasotracheal intubation, where oropharyngeal blood or secretions may obstruct the visual field on the monitor, thereby complicating video laryngoscopy. Moreover, the use of Magill forceps is markedly challenging or nearly unfeasible in this context, especially in pediatric cases. Furthermore, the substantial blade size of video laryngoscopes may restrict their applicability in individuals with limited oral apertures. This study aimed to review the literature on video laryngoscopy, discuss its clinical role in nasotracheal intubation, and address the challenges that anesthesiologists may encounter during the intubation process.

Air leakage due to the cuff hanging on the vocal cords during nasotracheal intubation: a case report.

Nasotracheal intubation is commonly performed under general anesthesia in oral and maxillofacial surgery. For the convenience of surgery, nasal Ring-Adair-Elwyn (RAE) tubes are mainly used. Because the nasal RAE tubes were bent in an "L" shape, the insertion depth was limited. Particularly, it is necessary to accurately determine the appropriate depth of the RAE tubes in children. Several types of nasal RAE tubes are used in the medical market, which vary in material and length. We performed endotracheal intubation using a nasal RAE tube for double-jaw surgery, but air leakage persisted even when the air pressure in the cuff was increased. When checked with a laryngoscope, it was confirmed that the tube was pushed out, and the cuff was caught on the vocal cords, causing air leakage. Since inserting the tube deeply did not solve the problem, replacing it with a nasal RAE tube (Polar™, Preformed Tracheal Tube, Smith Medical, Inc., USA) did not cause air leakage; thus, we reported this case.

An anesthetic management of head and neck cancer reconstructive surgery in a patient having hemophilia A: a case report.

Hemophilia A is a hemorrhagic disease caused by coagulation factor VIII deficiency. In head and neck cancer surgery, especially during a reconstructive one, complications can occur. These include hematomas due to bleeding which can then lead to flap ischemia, necrosis, and impaired wound healing. There are fewer cases of reconstructive surgery in patients with hemophilia A. Here in we report, a reconstructive surgery that involved mass resection, partial glossectomy (right), selective neck dissection (right, Levels I, II, III, IV), and reconstruction at the lateral arm free flap (left) in a 25-year-old man with hemophilia A. The surgery was successfully performed without any complications after pretreatment with Factor VIII concentrate, which has not been reported earlier.

Predictors of Red Blood Cell Transfusion in Bimaxillary Orthognathic Surgery: A Retrospective Study.

Background: Orthognathic surgery requires red blood cell (RBC) transfusions more frequently than other oral and maxillofacial surgeries. The purpose of this study was to identify reliable predictors for RBC transfusion during bimaxillary orthognathic surgery (BOS). Methods: This retrospective study reviewed 1,616 electronic medical records of patients who underwent BOS during a 5-year period at Seoul National University Dental Hospital. The perioperative variable data were collected from electronic medical records and analyzed by dividing patients into the two groups (non-transfusion and transfusion group). Results: Of the 1,616 patients, 1,311 patients were excluded. The remaining 305 patients were divided into non-transfusion (NTF, n = 256) and transfusion (TF, n = 49) groups. Univariate logistic regression analysis revealed that age, body mass index, the presence of several adjunctive surgeries (including genioplasty, extraction, and mandibular angle reduction), preoperative hemoglobin (Hb) and prothrombin time, surgical time, amount of fluid infusion and blood loss, and mean pulse rate during surgery were significant factors predicting RBC transfusion. Multivariate logistic regression analysis revealed that preoperative Hb and blood loss amount during surgery were significantly related to RBC transfusion in BOS patients. Conclusion: Since blood loss amounts could not be measured preoperatively, we found that the independent predictor associated with RBC transfusion during BOS was a low preoperative Hb level.

Comparison between total intravenous anesthesia and balanced anesthesia on postoperative opioid consumption in patients who underwent laparoscopic-assisted distal gastrectomy.

Remifentanil is the most frequently prescribed opioid for total intravenous anesthesia (TIVA) or balanced anesthesia (BA), due to its favorable pharmacological properties. However, several studies have reported opioid-induced hyperalgesia and/or acute tolerance after intraoperatively using remifentanil. In addition, it is imperative to control postoperative pain with lower doses of opioid anesthetic agents. Therefore, we compared the amount of opioid consumption between TIVA with propofol-remifentanil and BA with desflurane-remifentanil, to control postoperative pain in patients who underwent laparoscopic-assisted distal gastrectomy (LADG) with gastroduodenostomy.We retrospectively evaluated demographic variables (age, gender, height, weight, and smoking habits), the duration of general anesthesia (GA), and intraoperatively administered remifentanil consumption through the electronic medical records of patients who underwent LADG with gastroduodenostomy due to early stomach cancer. The primary outcome was postoperative opioid consumption during postoperative day (POD) 2. The secondary outcomes were the incidence of any rescue opioid analgesics administered, numeric rating scale, and various adverse effects during POD 2. We categorized the data in 2 patient groups to compare TIVA with propofol-remifentanil (TIVA group) to BA with desflurane-remifentanil (BA group) on the postoperative opioid analgesic consumption.We divided 114 patients into the TIVA (46 patients) and BA (68 patients) groups. Opioid consumption as a primary outcome was significantly higher in the BA group than in the TIVA group during POD 2 except in the post-anesthesia care unit. The cumulative opioid consumption was significantly higher in the BA than in the TIVA group. The incidence of rescue analgesic at POD 2 was higher in the BA than in the TIVA group. In the TIVA group, remifentanil consumption was higher, and the duration of GA was shorter than that in the BA group. No statistically significant differences were observed when comparing other variables.Our results indicated that the maintenance of GA with TIVA (propofol-remifentanil) reduces opioid consumption for postoperative pain control compared to BA (desflurane-remifentanil) in patients undergoing LADG with gastroduodenostomy.

Multiple implant therapy with multiple inductions of general anesthesia in non-compliant patients with schizophrenia: A case report.

The effectiveness of dental implants in patients with disability, who are non-compliant during treatment, is controversial because of their poor oral health. Thus, oral health-care and management in such patients is concerning. Moreover, limited information is available on prognosis after implant placement. Herein, we describe a patient with schizophrenia who underwent dental implantation under multiple inductions of general anesthesia (5 times) and required conservative treatment and tooth extraction for multiple dental caries and retained roots because of inadequate oral health-care. Postoperatively, fracture of the prosthodontics and progression of dental caries were observed, and with 3 additional inductions of general anesthesia, conservative treatment, implant surgery, and prosthesis implantation were conducted. Postoperative 12-month follow-up since the last prosthesis implantation showed successful results. For patients with schizophrenia, multiple implantation can reduce horizontal bone loss and achieve aesthetic results compared to treatment with removable prosthodontics and could serve as an alternative treatment modality.

Effects on postoperative nausea and vomiting of nefopam versus fentanyl following bimaxillary orthognathic surgery: a prospective double-blind randomized controlled trial.

BACKGROUND: Postoperative nausea and vomiting (PONV) frequently occurs following bimaxillary orthognathic surgeries. Compared to opioids, Nefopam is associated with lower incidences of PONV, and does not induce gastrointestinal tract injury, coagulopathy, nephrotoxicity, or fracture healing dysfunction, which are common side effects of Nonsteroidal anti-inflammatory drugs. We compared nefopam- and fentanyl-induced incidence of PONV in patients with access to patient-controlled analgesia (PCA) following bimaxillary orthognathic surgeries. METHODS: Patients undergoing bimaxillary orthognathic surgeries were randomly divided into nefopam and fentanyl groups. Nefopam 120 mg or fentanyl 700 µg was mixed with normal saline to a final volume of 120 mL. Patients were given access to nefopam or fentanyl via PCA. Postoperative pain intensity and PONV were measured at 30 minutes and 1 hour after surgery in the recovery room and at 8, 24, 48, and 72 hours after surgery in the ward. The frequency of bolus delivery was compared at each time point. RESULTS: Eighty-nine patients were enrolled in this study, with 48 in the nefopam (N) group and 41 in the fentanyl (F) group. PONV occurred in 13 patients (27.7%) in the N group and 7 patients (17.1%) in the F group at 8 hours post-surgery (P = 0.568), and there were no significant differences between the two groups at any of the time points. VAS scores were 4.4 ± 2.0 and 3.7 ± 1.9 in the N and F groups, respectively, at 8 hours after surgery (P = 0.122), and cumulative bolus delivery was 10.7 ± 13.7 and 8.6 ± 8.5, respectively (P = 0.408). There were no significant differences in pain or bolus delivery at any of the remaining time points. CONCLUSION: Patients who underwent bimaxillary orthognathic surgery and were given nefopam via PCA did not experience a lower rate of PONV compared to those that received fentanyl via PCA. Furthermore, nefopam and fentanyl did not provide significantly different postoperative pain control.

Percutaneous Epidural Adhesiolysis Using Inflatable Balloon Catheter and Balloon-less Catheter in Central Lumbar Spinal Stenosis with Neurogenic Claudication: A Randomized Controlled Trial.

BACKGROUND: When conventional interventional procedures fail, percutaneous epidural adhesiolysis (PEA), which has moderate evidence for successful treatment of lumbar spinal stenosis (LSS), has been recommended over surgical treatments. In a previous study, we demonstrated the efficacy of a newly developed inflatable balloon catheter for overcoming the access limitations of pre-existing catheters for patients with severe stenosis or adhesions. OBJECTIVES: This study compared the treatment response of combined PEA with balloon decompression and PEA only in patients with central LSS over 6 months of follow-up. STUDY DESIGN: This study used a randomized, single-blinded, active-controlled trial design. SETTING: This study took place in a single-center, academic, outpatient interventional pain management clinic. METHODS: This randomized controlled study included 60 patients with refractory central LSS who suffered from chronic lower back pain and/or lumbar radicular pain. Patients failed to maintain improvement for > 1 month with epidural steroid injection or PEA using a balloon-less catheter. Patients were randomly assigned to one of 2 interventions: balloon-less (n = 30) and inflatable balloon catheter (n = 30). The Numeric Rating Scale (NRS-11), Oswestry Disability Index (ODI), Global Perceived Effect of Satisfaction (GPES), and Medication Quantification Scale III were each measured at 1, 3, and 6 months after PEA. RESULTS: There was a significant difference between groups in NRS-11 reduction ≥ 50% (or 4 points), ODI reduction ≥ 30% (or 10 points), GPES ≥ 6 and ≥ 4 points at 6 months, and NRS-11 reduction ≥ 50% (or 4 points) at 3 months after PEA (P < .03). The proportion of successful responders was higher in the balloon group than in the balloon-less group throughout the total follow-up period. Furthermore, there was a statistically significant difference between groups at 6 months after PEA (P = .035). LIMITATIONS: The results may vary according to the definition of successful response. Follow-up loss in the present study seemed to be high. CONCLUSION: PEA using the inflatable balloon catheter leads to significant pain reduction and functional improvement compared to PEA using the balloon-less catheter in patients with central LSS.The study protocol was approved by our institutional review board (2012-0235), and written informed consent was obtained from all patients. The trial was registered with the Clinical Research Information Service (KCT 0002093). KEY WORDS: Balloon decompression, central, chronic pain, epidural adhesiolysis, lumbar, percutaneous, radiculopathy, spinal stenosis.

Airway management in pediatric tongue flap division for oronasal fistula closure: A case report.

Oronasal fistulae (ONF) could remain after surgery in some patients with cleft palate. ONF ultimately requires intraoral surgery, which may lead to perioperative airway obstruction. Tongue flap surgery is a technique used to repair ONF. During the second surgery for performing tongue flap division, the flap transplanted from the tongue dorsum to the palate of the patient acts as an obstacle to airway management, which poses a great challenge for anesthesiologists. In particular, anesthesiologists may face difficulty in airway evaluation and patient cooperation during general anesthesia for tongue flap division surgery in pediatric patients. The authors report a case of airway management using a flexible fiberoptic bronchoscope during general anesthesia for tongue flap division surgery in a 6-year-old child.

Recurrent ST segment elevations in a patient with asymptomatic early repolarization during head and neck surgery: implications of vasospastic angina.

A 57-year-old woman scheduled for cochlear implant removal exhibited preoperative electrocardiographic findings of early repolarization (ER). Four episodes of transient ST segment elevations during surgery raised suspicion for vasospastic angina (VA). In the post-anesthetic care unit, the patient complained of chest discomfort and received sublingual nitroglycerin with uncertain effect. The patient refused to proceed with postoperative invasive coronary angiography, resulting in inconclusive diagnosis. Intraoperative circumstances limit the diagnosis of VA, which emphasizes the need for further testing to confirm the diagnosis. When VA is suspected in patients with underlying ER, it is reasonable to consider invasive examination to establish the diagnosis and prevent recurrence of VA. If ST changes are observed during surgery in patients with preoperative ER, careful monitoring is recommended. Due to general anesthesia, the absence of patient symptoms limits the definitive diagnosis of those with suspected VA. Therefore, additional postoperative surveillance is recommended.

Orotracheal intubation in a patient with difficult airway by using fiberoptic nasotracheal intubation: A case report.

In cases of a difficult intubation where numerous intubation methods, including laryngoscopy, have failed, yet oral intubation is still necessary, the method of tube exchange after fiberoptic nasal intubation may be attempted. Fiberoptic nasal intubation allows intubation to be performed relatively easily when the laryngeal view grade is poor. We report a case in which our attempt at oral intubation for total maxillectomy with laryngoscopy and fiberoptic oral intubation had failed due to an unexpected difficult airway; subsequently, we successfully completed the surgery by performing fiberoptic nasal intubation to secure the airway, followed by using a tube exchanger to exchange to an oral endotracheal tube.

Cardiac arrest due to an unexpected acute myocardial infarction during head and neck surgery: A case report.

Major cardiac complication such as acute myocardial infarction can occur unexpectedly in patients without risk factors. We experienced cardiac arrest due to an unexpected acute myocardial infarction in a patient without any risk factors during head and neck reconstructive surgery. The patient was diagnosed with acute myocardial infarction after return of spontaneous circulation. With immediate percutaneous coronary intervention, the patient recovered without complications.

A case report: the use of ultrasound guided peripheral nerve block during above knee amputation in a severely cardiovascular compromised patient who required continuous anticoagulation.

RATIONALE: Although lower-extremity surgeries are mainly performed under general or central neuraxial anesthesia, ultrasound-guided peripheral nerve block (PNB) can be a good alternative, especially for patients who require continuous anticoagulation treatment and present with poor cardiovascular conditions. PATIENTS CONCERNS: The patient required continuous anticoagulation treatment due to the high risk of thromboembolism and poor cardiovascular conditions. DIAGNOSES: The patient required lower-extremity amputation due to atherosclerotic and thromboembolic obstruction. INTERVENTIONS: We decided to progress the operation under peripheral nerve block. The sciatic, femoral, lateral femoral cutaneous nerve and anterior branch of the obturator nerve were blocked under ultrasound guidance. Sixty ml of a local anesthetic (equal mix of 1% lidocaine and 0.375% ropivacaine) was administered for the block. OUTCOMES: Sufficient sensory block at the area of amputation was obtained, and the patient's vital signs were stable throughout surgery. LESSONS: Ultrasound-guided peripheral nerve block can be an excellent anesthetic technique for patients receiving radical surgery at the proximal lower extremities, especially patients who are critically ill and considered high risk.

Perioperative red blood cell transfusion in orofacial surgery.

In the field of orofacial surgery, a red blood cell transfusion (RBCT) is occasionally required during double jaw and oral cancer surgery. However, the question remains whether the effect of RBCT during the perioperative period is beneficial or harmful. The answer to this question remains challenging. In the field of orofacial surgery, transfusion is performed for the purpose of oxygen transfer to hypoxic tissues and plasma volume expansion when there is bleeding. However, there are various risks, such as infectious complications (viral and bacterial), transfusion-related acute lung injury, ABO and non-ABO associated hemolytic transfusion reactions, febrile non-hemolytic transfusion reactions, transfusion associated graft-versus-host disease, transfusion associated circulatory overload, and hypersensitivity transfusion reaction including anaphylaxis and transfusion-related immune-modulation. Many studies and guidelines have suggested RBCT is considered when hemoglobin levels recorded are 7 g/dL for general patients and 8-9 g/dL for patients with cardiovascular disease or hemodynamically unstable patients. However, RBCT is occasionally an essential treatment during surgeries and it is often required in emergency cases. We need to comprehensively consider postoperative bleeding, different clinical situations, the level of intra- and postoperative patient monitoring, and various problems that may arise from a transfusion, in the perspective of patient safety. Since orofacial surgery has an especially high risk of bleeding due to the complex structures involved and the extensive vascular distribution, measures to prevent bleeding should be taken and the conditions for a transfusion should be optimized and appropriate in order to promote patient safety.

Anesthetic management for simultaneous drug-induced sleep endoscopy and maxillomandibular advancement in a patient with obstructive sleep apnea.

Drug-induced sleep endoscopy (DISE) is used to identify areas of upper airway obstruction, which occurs when patients with obstructive sleep apnea (OSA) snore. DISE enables effective diagnosis and appropriate treatment of the obstruction site. Among surgical treatment methods for OSA, maxillomandibular advancement surgery (MMA) is performed to move a jaw forward; the surgery has a high success rate for OSA treatment. In DISE, anesthetics such as propofol and midazolam must be administered to induce snoring while the patient is deeply sedated for an accurate diagnosis to be made. When inducing deep sedation in a patient with OSA, airway obstruction may increase, causing oxygen saturation to drop; airway interventions are necessary in such cases. Effective DISE and MMA surgery can be performed by administering propofol through target-controlled infusion while monitoring the bispectral index (BIS).

Comparison of the efficacy and safety of 2% lidocaine HCl with different epinephrine concentration for local anesthesia in participants undergoing surgical extraction of impacted mandibular third molars: A multicenter, randomized, double-blind, crossover, phase IV trial.

BACKGROUND: The most commonly impacted tooth is the third molar. An impacted third molar can ultimately cause acute pain, infection, tumors, cysts, caries, periodontal disease, and loss of adjacent teeth. Local anesthesia is employed for removing the third molar. This study aimed to evaluate the efficacy and safety of 2% lidocaine with 1:80,000 or 1:200,000 epinephrine for surgical extraction of bilateral impacted mandibular third molars. METHODS: Sixty-five healthy participants underwent surgical extraction of bilateral impacted mandibular third molars in 2 separate visits while under local anesthesia with 2% lidocaine with different epinephrine concentration (1:80,000 or 1:200,000) in a double-blind, randomized, crossover trial. Visual analog scale pain scores obtained immediately after surgical extraction were primarily evaluated for the 2 groups receiving different epinephrine concentrations. Visual analog scale pain scores were obtained 2, 4, and 6 hours after administering an anesthetic. Onset and duration of analgesia, onset of pain, intraoperative bleeding, operator's and participant's overall satisfaction, drug dosage, and hemodynamic parameters were evaluated for the 2 groups. RESULTS: There were no statistically significant differences between the 2 groups in any measurements except hemodynamic factors (P >.05). Changes in systolic blood pressure and heart rate following anesthetic administration were significantly greater in the group receiving 1:80,000 epinephrine than in that receiving 1:200,000 epinephrine (P ≤.01). CONCLUSION: The difference in epinephrine concentration between 1:80,000 and 1:200,000 in 2% lidocaine liquid does not affect the medical efficacy of the anesthetic. Furthermore, 2% lidocaine with 1:200,000 epinephrine has better safety with regard to hemodynamic parameters than 2% lidocaine with 1:80,000 epinephrine. Therefore, we suggest using 2% lidocaine with 1:200,000 epinephrine rather than 2% lidocaine with 1:80,000 epinephrine for surgical extraction of impacted mandibular third molars in hemodynamically unstable patients.

Smoking May Increase Postoperative Opioid Consumption in Patients Who Underwent Distal Gastrectomy With Gastroduodenostomy for Early Stomach Cancer: A Retrospective Analysis.

OBJECTIVES: Although nicotine has an analgesic effect, the incidence and severity of chronic pain is higher in smokers than nonsmokers. Acute pain is more intense in smokers during the perioperative period. This study evaluated whether smokers require higher doses of opioid to reduce pain when they undergo surgery. METHODS: A retrospective review of 236 patients who had intravenous patient-controlled analgesia after distal gastrectomy with gastroduodenostomy between October 2013 and September 2014 was performed to analyze the difference in postoperative opioid requirements between smokers and nonsmokers. Total opioid consumption was observed from the day of operation to postoperative day 2. Patients were grouped into smokers (N=117) and nonsmokers (N=119) for comparison. Simple and multiple regression analyses were performed to identify predictors of postoperative opioid requirements. RESULTS: Opioid consumption by male smokers was higher than nonsmokers. Multiple regression analysis showed that age, smoking, and amount of intraoperative remifentanil were the only significant factors for postoperative opioid requirements. DISCUSSION: Our results suggest that smokers undergoing distal gastrectomy with gastroduodenostomy required more opioid than nonsmokers for postoperative pain. Old age, smoking status, and increment of remifentanil use seemed to be predictors of postoperative opioid consumption.

Comparison of false-negative/positive results of intraoperative evoked potential monitoring between no and partial neuromuscular blockade in patients receiving propofol/remifentanil-based anesthesia during cerebral aneurysm clipping surgery: A retrospective analysis of 685 patients.

Although the elicited responses of motor evoked potential (MEP) monitoring are very sensitive to suppression by anesthetic agents and muscle relaxants, the use of neuromuscular blockade (NMB) during MEP monitoring is still controversial because of serious safety concerns and diagnostic accuracy. Here, we evaluated the incidence of unacceptable movement and compared false-negative MEP results between no and partial NMB during cerebral aneurysm clipping surgery. We reviewed patient medical records for demographic data, anesthesia regimen, neurophysiology event logs, MEP results, and clinical outcomes. Patients were divided into 2 groups according to the intraoperative use of NMB: no NMB group (n = 276) and partial NMB group (n = 409). We compared the diagnostic accuracy of MEP results to predict postoperative outcomes between both groups. Additionally, we evaluated unwanted patient movement during MEP monitoring in both groups. Of the 685 patients, 622 (90.8%) manifested no intraoperative changes in MEP and no postoperative motor deficits. Twenty patients showed postoperative neurologic deficits despite preserved intraoperative MEP. False-positive MEP results were 3.6% in the no NMB group and 3.9% in the partial NMB group (P = 1.00). False-negative MEP results were 1.1% in the no NMB group and 4.2% in the partial NMB group (P = 0.02). No spontaneous movement or spontaneous respiration was observed in either group. Propofol/remifentanil-based anesthesia without NMB decreases the stimulation intensity of MEPs, which may reduce the false-negative ratio of MEP monitoring during cerebral aneurysm surgery. Our anesthetic protocol enabled reliable intraoperative MEP recording and patient immobilization during cerebral aneurysm clipping surgery.