Comparison of rocuronium priming vs. standard rapid sequence intubation technique in emergency department patients requiring intubation.

OBJECTIVE: In our study, we aimed to compare the effect of standard rapid sequence intubation protocol and the application of rocuronium priming technique on the procedure time and hemodynamic profile. METHODS: Patients who applied to the emergency department and needed rapid sequence intubation were included in our study, which we conducted with a randomized controlled design. Randomization in the study was made according to the order of arrival of the cases. Rapid sequence intubation was performed in the standard group. In the priming group, 10% of the rocuronium dose was administered approximately 3 min before the induction agent. Intubation time, amount of drug used, vital signs, and end-tidal CO2 level before and after intubation used to confirm intubation were recorded. RESULTS: A total of 52 patients were included in the study, of which 26 patients were included in the standard group and 26 patients in the priming group. While intubation time was 121.2±21.9 s in the standard group, it was calculated as 68.4±11.6 s in the priming group (p<0.001). While the mean arterial pressure was 58.3±26.6 mmHg in the standard group after intubation, it was 80.6±21.1 mmHg in the priming group (p=0.002). CONCLUSION: It was observed that priming with rocuronium shortened the intubation time and preserved the hemodynamic profile better. CLINICAL TRIAL REGISTRATION NUMBER: NCT05343702.

Rocuronium Dosing by Ideal vs Total Body Weight in Obesity: A Prospective, Observational Non-inferiority Study.

Background: Providing adequate paralysis and appropriate sedation is challenging in patients with obesity during rapid sequence intubation (RSI). Pharmacokinetic parameters play an important role in dosing of rocuronium due to low lipophilicity. Rocuronium may be dosed based on ideal body weight (IBW). Current guidelines do not offer recommendations for dosing in the setting of obesity. Dosing depends on clinician preference based on total body weight (TBW) or IBW. Objective: In this study we performed non-inferiority analysis to compare the intubation conditions, duration of paralysis, and incidence of new-onset tachycardia or hypertension after intubation in obese patients requiring RSI in the emergency department (ED). Methods: This was a single-center, prospective, observational study. Eligible for enrollment were adult patients with a TBW ≥30% IBW or body mass index ≥30 kilograms per meters squared who presented to the ED requiring RSI with the use of rocuronium. Rocuronium was dosed according to intubating physicians' preference. Physicians completed a survey assessing intubation conditions. Height and weight used for the calculation of the dose, the dose of rocuronium, time of administration, and time of muscle function recovery were recorded. Endpoints assessed included grading of view during laryngoscopy, first-past success, and duration of paralysis. Results: In total, 96 patients were included, 54 in TBW and 42 in IBW. The TBW cohort received a mean of 1 milligram per kilogram (mg/kg) compared to 0.71 mg/kg in the IBW group. Excellent intubation conditions were observed in 68.5% in the TBW group and 73.8% in the IBW group. The non-inferiority analysis for relative risk of excellent intubation was 1.12 (P = 0.12, [90% CI 0.80-1.50]). Conclusion: Non-inferiority analysis suggests that IBW dosing provides similar optimal intubation conditions when compared to TBW dosing, but the noninferiority comparison did not reach statistical significance. This study was unable to show statistical non-inferiority for IBW dosing.

The effect of rocuronium priming dose based on actual versus corrected body weight in modified rapid sequence intubation.

Background: Rapid sequence intubation (RSI) is a technique that allows patients to be quickly intubated and have the airway secured. Aims: The purpose of this study was to investigate the effect of rocuronium priming and intubation dose calculated according to actual body weight (ABW) or corrected body weight (CBW) on the neuromuscular block and intubation quality in rapid sequence induction and intubation (RSII). Patients and Methods: This prospective randomized, double-blind study was conducted on a total of 60 patients randomized into two groups using the closed-envelope method between January 2021 and December 2021, with 30 individuals in each group. In group 1, CBW was used with the formula to calculate the neuromuscular blocking drug (NMBD) dose. The ABW of patients was used to calculate the NMBD dose in group 2. Results: The data of 50 female patients who underwent group 1 (CBW, n = 25) and group 2 (ABW, n = 25) were analyzed. Age, weight, height, body mass index (BMI), quality of laryngoscopy, post-priming side effects, mean arterial pressure (MAP), and heart rate (HR) values did not differ across the groups. When train-of-four (TOF) values, priming and intubation dose, and laryngoscopy time were compared, a statistically significant difference was found between the two groups of TOF count (TOF C) 1 (the duration of action). Conclusion: This study suggests that the application of rocuronium priming and intubation dose according to CBW in RSII, especially during the pandemic, provided similar intubation conditions as the application according to ABW, while its shorter duration of action shows that it can be preferred, especially in short-term surgical cases.

Comparison of a Modern Digital Mechanomyograph to a Mechanomyograph Utilizing an Archival Grass Force Transducer.

BACKGROUND: Mechanomyography is the traditional gold standard research technique for quantitative assessment of neuromuscular blockade. Mechanomyography directly measures the isometric force generated by the thumb in response to ulnar nerve stimulation. Researchers must construct their own mechanomyographs since commercial instruments are no longer available. A mechanomyograph was constructed, and its performance was compared against an archival mechanomyography system from the 1970s that utilized an FT-10 Grass force transducer, hypothesizing that train-of-four ratios recorded on each device would be equivalent. METHODS: A mechanomyograph was constructed using 3D-printed components and modern electronics. An archival mechanomyography system was assembled from original components, including an FT-10 Grass force transducer. Signal digitization for computerized data collection was utilized instead of the original paper strip chart recorder. Both devices were calibrated with standard weights to demonstrate linear voltage response curves. The mechanomyographs were affixed to opposite arms of patients undergoing surgery, and the train-of-four ratio was measured during the onset and recovery from rocuronium neuromuscular blockade. RESULTS: Calibration measurements exhibited a positive linear association between voltage output and calibration weights with a linear correlation coefficient of 1.00 for both mechanomyography devices. The new mechanomyograph had better precision and measurement sensitivity than the archival system: 5.3 mV versus 15.5 mV and 1.6 mV versus 5.7 mV, respectively (P < 0.001 for both). A total of 767 pairs of train-of-four ratio measurements obtained from eight patients had positive linear association (R 2 = 0.94; P < 0.001). Bland-Altman analysis resulted in bias of 3.8% and limits of agreement of -13% and 21%. CONCLUSIONS: The new mechanomyograph resulted in similar train-of-four ratio measurements compared to an archival mechanomyography system utilizing an FT-10 Grass force transducer. These results demonstrated continuity of gold standard measurement of neuromuscular blockade spanning nearly 50 yr, despite significant changes in the instrumentation technology.

A Surgeon-Centered Neuromuscular Block Protocol Improving Intraoperative Neuromonitoring Outcome of Thyroid Surgery.

Background: Neuromuscular blocking agents provide muscular relaxation for tracheal intubation and surgery. However, the degree of neuromuscular block may disturb neuromuscular transmission and lead to weak electromyography during intraoperative neuromonitoring. This study aimed to investigate a surgeon-friendly neuromuscular block degree titrated sugammadex protocol to maintain both intraoperative neuromonitoring quality and surgical relaxation during thyroid surgery. Methods: A total of 116 patients were enrolled into two groups and underwent elective thyroid surgery with intraoperative neuromonitoring. All patients followed a standardized intraoperative neuromonitoring protocol with continuous neuromuscular transmission monitoring and received 0.6 mg/kg rocuronium for tracheal intubation. Patients were allocated into two groups according to the degree of neuromuscular block when the anterior surface of the thyroid gland was exposed. The neuromuscular block degree was assessed by the train-of-four (TOF) count and ratio. Patients in group I received sugammadex 0.25 mg/kg for non-deep neuromuscular block degree (TOF count = 1~4). Patients in group II were administered sugammadex 0.5 mg/kg for deep neuromuscular block degree (TOF count = 0). The quality of the intraoperative neuromonitoring was measured using the V1 electromyography (EMG) amplitude. An amplitude less than 500 µV and greater than 500 µV was defined as weak and satisfactory, respectively. Results: The quality of the intraoperative neuromonitoring was not different between groups I and II (satisfactory/weak: 75/1 vs. 38/2, P = 0.14). The quality of surgical relaxation was acceptable after sugammadex injection and showed no difference between groups [55/76 (72.3%) in group I vs. 33/40 (82.5%) in group II, P = 0.23]. Conclusions: This surgeon-centered sugammadex protocol guided by neuromuscular block degree (0.5 mg/kg for deep block and 0.25 mg/kg for others) showed comparably high intraoperative neuromonitoring quality and adequate surgical relaxation. The results expanded the practicality of sugammadex for precise neuromuscular block management during monitored thyroidectomy.

Polymorphisms contribute to differences in the effect of rocuronium in Chinese patients.

Rocuronium is widely utilized in clinical general anaesthesia, and individual differences in pharmacology and clearance have been observed. Two hundred thirty-six Chinese patients undergoing selective thyroid/breast mass resection were studied. Total intravenous anaesthesia was induced with a single dose of propofol (2 mg·kg-1 ), sufentanil (0.5 µg·kg-1 ), and rocuronium (0.6 mg·kg-1 ) and maintained with propofol (3-5 mg·kg-1 ·h-1 ) and remifentanil (0.2-0.4 µg·kg-1 ·min-1 ). Intubation conditions and a train-of-four index of patients were utilized to assess the effects and duration of rocuronium. The data from 228 patients were analysed and reported. Genotypes NR1I2 rs2472677 C > T, NR1I2 rs6785049 G > A, SLCO1B1 rs4363657 T > C, SLCO1A2 rs4762699 T > C, and UGT1A1 rs4148323 G > A contributed to individual variation in rocuronium. Of the clinical variables tested, age, BMI, total dose of propofol, NR1I2 rs2472677, and SLCO1A2 rs4762699 correlated significantly (P < 0.05 for all) with the clinical duration or total clinical action time of rocuronium in a multiple linear regression model. No significant interactions were observed in intubation conditions. Genetic variations in NR1I2 rs2472677, NR1I2 rs6785049, SLCO1B1 rs4363657, SLCO1A2 rs4762699, and UGT1A1 rs4148323 were related to extensive interindividual variability in the clinical duration and total clinical action time of rocuronium.

Investigation of potential neuropharmacological activity of neostigmine-glycopyrrolate for intraoperative neural monitoring in thyroid surgery.

Intraoperative neuromonitoring (IONM) is frequently used in thyroid surgery to reduce recurrent laryngeal nerve injury. The use of neuromuscular blockade agent to facilitate tracheal intubation, is a common cause of IONM failure. We performed a retrospective analysis to assess the efficacy of neostigmine-glycopyrrolate as a neuromuscular blockade reversal agent for IONM during thyroid surgery. Rocuronium (0.6 mg/kg) was administered for muscle relaxation. Neostigmine (2 mg) and glycopyrrolate (0.4 mg) were administered immediately after intubation. Cricothyroid muscle-twitch response upon external branch of superior laryngeal nerve stimulation and electromyography amplitudes of vagal and recurrent laryngeal nerves before (V1, R1) and after thyroid resection (V2, R2) were recorded. Fifty patients (23 males, 27 females) were included in the analysis. The diagnoses comprised 43 papillary thyroid carcinomas and seven benign diseases. The mean time between rocuronium injection and neostigmine-glycopyrrolate injection was 5.1 ± 1.2 min, and the mean time from neostigmine-glycopyrrolate injection to successful cricothyroid muscle twitching upon external branch of superior laryngeal nerve stimulation was 21.0 ± 4.5 min. All patients had V1 and R1 amplitudes of more than 500 µV each, with mean V1 and R1 amplitudes of 985.3 ± 471.6 µV and 1177.2 ± 572.7 µV, respectively. Neostigmine-glycopyrrolate was effectively used as a neuromuscular blockade reversal agent for IONM in thyroid surgeries without a significant increase in bucking events. Administration of neostigmine-glycopyrrolate immediately after intubation can be recommended for successful NMB reversal to facilitate IONM during thyroid surgery.

What do we know about perioperative hypersensitivity reactions and what can we do to improve perioperative safety?

Hypersensitivity reactions are an important aspect of perioperative care and are a crucial interdisciplinary issue in anaesthesiological practice, as well as allergological and laboratory diagnostics. This phenomenon was observed as early as the 1980s and 1990s in Western European countries, and knowledge on this subject has grown significantly over time. Although hypersensitivity reactions are not frequent events (the incidence of perioperative hypersensitivity reactions ranges from 1:386 to 1:13 000 procedures, with higher frequency - 1 per 6500 general anaesthesias with neuromuscular blocking agents administrations), their courses are unfortunately serious and life-threatening. It should also be noted that there is no information regarding the occurrence of perioperative hypersensitivity reactions in many countries. Hence, global assessment of the problem is underestimated. The primary source of actual knowledge comes from epidemiological studies, which indicate an increasing frequency of hypersensitivity reaction occurrence and changes in aetiological factors. The first report from France (1984 to 1989) described two main causes - neuromuscular blocking agents and hypnotic agents. The following years confirmed an increase in perioperative hypersensitivity reactions associated with latex and antibiotics. The most recent data from the National Audit Project 6 indicated increased participation of antibiotics, chlorhexidine, and contrast agents. The results of epidemiological analyses are the basis of medical management guidelines and practice modification. Thanks to the activity of many organisations monitoring the intensity and nature of perioperative hypersensitivity reactions, guidelines for diagnostics and management have been developed. This article presents the results of numerous studies, including the first and the most recent, from various geographical regions. The clinical significance, pathogenesis mechanisms are also discussed. This publication also presents important directions for further scientific and epidemiological research on perioperative hypersensitivity reactions.Key messagesThe incidence of perioperative hypersensitivity reactions ranges from 1:386 to 1:13 000 procedures, with higher frequency - 1 per 6500 general anaesthesias with neuromuscular blocking agents administrations.Reactions may occur during the first episode of anaesthesia, most frequently in the induction of general anaesthesia, and much less frequently during postoperative follow-up.The first reports of perioperative hypersensitivity reaction come from the 1990s, and knowledge on this subject has grown significantly over time.In many countries, multidisciplinary teams and organisations have been established to identify, monitor the occurrence of this phenomenon, and have set the directions of medical activities and have changed the rules and recommendations.There is no information about the occurrence of perioperative hypersensitivity reactions in many countries, and global assessment of the problem is underestimated. Additionally, there is a great need to develop a system to monitor their occurrence in other countries.The long-term epidemiologic studies have demonstrated variability in pharmacologic triggers. However, the main pharmacological substances (antibiotics, muscle relaxants, disinfectans, contrast agents) are related to aspects of patient safety during anaesthesia.

A randomized trial evaluating the safety profile of sugammadex in high surgical risk ASA physical class 3 or 4 participants.

BACKGROUND: The aim of this randomized, double-blind trial was to evaluate the safety and tolerability profile, including cardiac safety, of sugammadex-mediated recovery from neuromuscular block in participants undergoing surgery who met the American Society of Anesthesiologists (ASA) Physical Class 3 or 4 criteria. Specifically, this study assessed the impact of sugammadex on cardiac adverse events (AEs) and other prespecified AEs of clinical interest. METHODS: Participants meeting ASA Class 3 and 4 criteria were stratified by ASA Class and NMBA (rocuronium or vecuronium) then randomized to one of the following: 1) Moderate neuromuscular block, sugammadex 2 mg/kg; 2) Moderate neuromuscular block, neostigmine and glycopyrrolate (neostigmine/glycopyrrolate); 3) Deep neuromuscular block, sugammadex 4 mg/kg; 4) Deep neuromuscular block, sugammadex 16 mg/kg (rocuronium only). Primary endpoints included incidences of treatment-emergent (TE) sinus bradycardia, TE sinus tachycardia and other TE cardiac arrhythmias. RESULTS: Of 344 participants randomized, 331 received treatment (61% male, BMI 28.5 ± 5.3 kg/m2, age 69 ± 11 years). Incidence of TE sinus bradycardia was significantly lower in the sugammadex 2 mg/kg group vs neostigmine/glycopyrrolate. The incidence of TE sinus tachycardia was significantly lower in the sugammadex 2 and 4 mg/kg groups vs neostigmine/glycopyrrolate. No significant differences in other TE cardiac arrythmias were seen between sugammadex groups and neostigmine/glycopyrrolate. There were no cases of adjudicated anaphylaxis or hypersensitivity reactions in this study. CONCLUSIONS: Compared with neostigmine/glycopyrrolate, incidence of TE sinus bradycardia was significantly lower with sugammadex 2 mg/kg and incidence of TE sinus tachycardia was significantly lower with sugammadex 2 mg/kg and 4 mg/kg. These results support the safety of sugammadex for reversing rocuronium- or vecuronium-induced moderate and deep neuromuscular block in ASA Class 3 or 4 participants. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03346057 .

Effects of age on sugammadex reversal of neuromuscular blockade induced by rocuronium in Chinese children: a prospective pilot trial.

BACKGROUND: Sugammadex reverses neuromuscular blockade induced by steroidal relaxants. We compared the recovery for neuromuscular blockade reversal with sugammadex in children aged 1-12 years. METHODS: From August 2019 to August 2020, patients who received 2.0 mg·kg- 1 sugammadex for neuromuscular blockade reversal after surgery were recruited. The primary outcome was the time for the train-of-four ratio (TOFR) to recover to 0.9; secondary outcomes included the incidence of the TOFR < 0.9, extubation time, length of stay at the post-anesthesia care unit, and adverse events. Hemodynamic parameters before and 5 min after sugammadex administration and vital signs in the recovery room were also recorded. RESULTS: Eighty-six children were recruited (1 to < 3 years, n = 23; 3 to < 5 years, n = 33; 5 to ≤12 years, n = 30). Intergroup differences in the recovery of the TOFR to 0.9 were not statistically significant (F = 0.691, p = 0.504). Recurrence of the TOFR < 0.9 was not observed in any group. Five minutes after sugammadex administration, the heart rates of patients aged 3 to < 5 and 5 to ≤12 years were significantly lower than those at baseline (p < 0.05). Extubation time was similar in patients aged 1 to ≤12 years. Length of stay and end-tidal capnography at the post-anesthesia care unit as well as adverse events did not differ significantly. CONCLUSION: A moderate (TOF count two) rocuronium-induced neuromuscular blockade can be effectively and similarly reversed with sugammadex 2 mg·kg- 1 in Chinese children aged 1-12 years. TRIAL REGISTRATION: Chinese Clinical Trial Registry: ChiCTR1900023715 (June 8, 2019).

The influence of neuromuscular blockade on phase lag entropy and bispectral index: A randomized, controlled trial.

The aim of this study is to compare the effects of neuromuscular blockade (NMB) on phase lag entropy (PLE) and the bispectral index (BIS). We recorded the BIS, electromyograph (EMG) activity on a BIS monitor (EMG_BIS), PLE, and EMG activity on a PLE monitor (EMG_PLE) in 40 patients receiving general anesthesia. During the awake state, we analyzed the changes in parameters before and 2 min after the eyes were closed. During sedation, we compared the changes in the parameters before and at 4 min after injecting rocuronium (group R) or normal saline (group C) between the two groups. During anesthesia, we compared the changes in parameters before and at 4 min after injecting sugammadex (group B) or normal saline (group D) between the two groups. During the awake state, the BIS, EMG_BIS, and EMG_PLE, but not PLE, decreased significantly with closed eyes. An effect of EMG on the BIS was evident, but not on PLE. During sedation, the BIS decreased with the decrease in EMG_BIS regardless of NMB caused by rocuronium, but NMB decreased PLE, although the degree of the decrease in EMG_PLE after NMB was similar to that after placebo. To determine the effect of NMB on electroencephalograms (EEGs) in groups R and C, we plotted the power spectra before and at 4 min after injecting rocuronium or normal saline. Changes in slow and delta frequency bands were observed at 4 min after injecting rocuronium relative to before injecting rocuronium. There was no effect of EMG on either the BIS or PLE during anesthesia. In conclusion, the effect of electromyograph activity and/or neuromuscular blockade on BIS or PLE depends on the level of consciousness.

General versus general anaesthesia combined with caudal block in laparoscopic-assisted Soave pull-through of Hirschsprung disease: a retrospective study.

BACKGROUND: Caudal block is one of the most preferred regional anesthesia for sub-umbilical region surgeries in the pediatric population. However, few studies are available on caudal block performed in laparoscopic-assisted Soave pull-through of Hirschsprung disease (HD). We aimed to compare general anesthesia (GA) and general anesthesia combined with caudal block (GA + CA) in laparoscopic-assisted Soave pull-through of HD. METHODS: A retrospective review was performed in children with HD operated in our hospital between 2017 and 2020. Patients were divided into the GA and GA + CA group. The primary outcome was the duration of operation, and secondary outcomes included intraoperative hemodynamic changes, the Face, Legs, Activity, Cry, Consolability (FLACC) scale, dose of anesthetics, and incidence of side effects. RESULTS: A total of 47 children with HD were included in the study, including 20 in the GA group and 27 in the GA + CA Group. The two groups were similar in age, gender, weight and type of HD (P > 0.05). The GA + CA group had significantly shorter duration of operation (especially the transanal operation time) (median 1.20 h vs. 0.83 h, P < 0.01) and recovery time (mean 18.05 min vs. 11.89 min, P < 0.01). The mean doses of sufentanil and rocuronium bromide during the procedure and FLACC scores at 1 h and 6 h after surgery were also lower in the GA + CA group (p < 0.01). The hemodynamic changes in the GA + CA group were more stable at time of t2 (during transanal operation) and t3 (10 min after transanal operation), but there was no significant difference in the incidence of postoperative side effects between the two groups (P = 1.000). CONCLUSION: General anesthesia combined with caudal block can shorten the duration of operation, and provide more stable intraoperative hemodynamics and better postoperative analgesia.

BET 2: Is the use of long-acting neuromuscular blocking agents for intubation associated with reduced provision of postintubation sedation?

A short cut review was conducted to assess if the use of rocuronium in the ED was associated with a decrease in the provision of postintubation sedation. Four papers were identified that presented the best evidence to answer the question. Again the studies, relevant outcomes, results and weaknesses are tabulated. All the identified studies were retrospective and there was a plethora of outcome measures used. When compared with suxamethonium, rocuronium was associated with a delayed initiation and reduced dose of postintubation sedation.

Comparison between the trapezius and adductor pollicis muscles as an acceleromyography monitoring site for moderate neuromuscular blockade during lumbar surgery.

Acceleromyography at the adductor pollicis located in a distal part of the body may not reflect the degree of neuromuscular blockade (NMB) at the proximally located muscles manipulated during lumbar surgery. We investigated the usefulness and characteristics of acceleromyographic monitoring at the trapezius for providing moderate NMB during lumbar surgery. Fifty patients were randomized to maintain a train-of-four count 1-3 using acceleromyography at the adductor pollicis (group A; n = 25) or the trapezius (group T; n = 25). Total rocuronium dose administered intraoperatively [mean ± SD, 106.4 ± 31.3 vs. 74.1 ± 17.6 mg; P < 0.001] and surgical satisfaction (median [IQR], 7 [5-8] vs. 5 [4-5]; P < 0.001) were significantly higher in group T than group A. Lumbar retractor pressure (88.9 ± 12.0 vs. 98.0 ± 7.8 mmHg; P = 0.003) and lumbar muscle tone in group T were significantly lower than group A. Time to maximum block with an intubating dose was significantly shorter in group T than group A (44 [37-54] vs. 60 [55-65] sec; P < 0.001). Other outcomes were comparable. Acceleromyography at the trapezius muscle during lumbar surgery required a higher rocuronium dose for moderate NMB than the adductor pollicis muscle, thereby the consequent deeper NMB provided better surgical conditions. Trapezius as proximal muscle may better reflect surgical conditions of spine muscle.

AutoFlow® versus volume-controlled ventilation for laparoscopic gynecological surgery using LMA® ProSeal™: a randomized controlled trial.

BACKGROUND: During laparoscopic gynecological surgery, increased peak airway pressure (PAWP) can cause airway leak upon ventilation with the LMA® ProSeal™. We hypothesized that compared with the use of volume-controlled ventilation (VCV), the use of the AutoFlow® mode would decrease PAWP and airway leak during laparoscopic gynecological surgery with LMA ProSeal. METHODS: This single-center, randomized, controlled trial allocated 80 adult women undergoing elective laparoscopic gynecological surgery to one of two groups, namely, the AutoFlow group or the VCV group. Ventilation settings for both groups were 8 ml/kg of tidal volume and 5 cmH2O of positive end-expiratory pressure, and respiratory rate was adjusted to maintain end-tidal carbon dioxide at 35-40 mmHg. Airway leak, PAWP, and other ventilatory parameters and vital signs were recorded at four timepoints (1, 1 min after insertion of the gastric tube; 2, 2 min after intravenous administration of rocuronium 0.6-0.8 mg/kg; 3, 1 min after initiation of pneumoperitoneum; and 4, 1 min after changing to the Trendelenburg position). The primary outcome was PAWP during pneumoperitoneum and in the Trendelenburg position, whereas the secondary outcomes included PAWP at other timepoints and airway leak development. We used the Mann-Whitney U test for PAWP and Fisher's exact test for comparing airway leak among the groups. RESULTS: Data from 40 patients in the AutoFlow group and 39 in the VCV group were used for analysis. PAWP at pneumoperitoneum pressure and in the Trendelenburg position was significantly lower in the AutoFlow group than in the VCV group [median (interquartile range), 16 (15-18) cmH2O vs. 18 (17-19) cmH2O; P < 0.001]. Similarly, patients in the AutoFlow group showed lower PAWP at the other three timepoints measured. Airway leak occurred in four patients in the AutoFlow group and in two patients in the VCV group; however, this incidence was not significantly different (P = 0.68). CONCLUSIONS: Even though AutoFlow ventilation decreased PAWP, it did not reduce the incidence of airway leak compared with VCV during laparoscopic gynecological surgery with the LMA ProSeal. TRIAL REGISTRATION: UMIN Clinical Trials Registry, identifier UMIN000023173 .

Sugammadex Versus Neostigmine for Reversal of Rocuronium Neuromuscular Block in Patients Having Catheter-Based Neurointerventional Procedures: A Randomized Trial.

BACKGROUND: Catheter-based endovascular neurointerventions require deep neuromuscular blocks during the procedure and rapid subsequent recovery of strength to facilitate neurological evaluation. We tested the primary hypothesis that sugammadex reverses deep neuromuscular blocks faster than neostigmine reverses moderate neuromuscular blocks. METHODS: Patients having catheter-based cerebral neurointerventional procedures were randomized to: (1) deep rocuronium neuromuscular block with posttetanic count 1 to 2 and 4-mg/kg sugammadex as the reversal agent or (2) moderate rocuronium neuromuscular block with train-of-four (TOF) count 1 during the procedure and neuromuscular reversal with 0.07-mg/kg neostigmine to a maximum of 5 mg. Recovery of diaphragmatic function was assessed by ultrasound at baseline before the procedure and 90 minutes thereafter. The primary outcome-time to reach a TOF ratio ≥0.9 after administration of the designated reversal agent-was analyzed with a log-rank test. Secondary outcomes included time to successful tracheal extubation and the difference between postoperative and preoperative diaphragmatic contraction speed and distance. RESULTS: Thirty-five patients were randomized to sugammadex and 33 to neostigmine. Baseline characteristics and surgical factors were well balanced. The median time to reach TOF ratio ≥0.9 was 3 minutes (95% confidence interval [CI], 2-3 minutes) in patients given sugammadex versus 8 minutes (95% CI, 6-10 minutes) in patients given neostigmine. Sugammadex was significantly faster by a median of 5 minutes (95% CI, 3-6 minutes; P < .001). However, times to tracheal extubation and diaphragmatic function at 90 minutes did not differ significantly. CONCLUSIONS: Sugammadex reversed deep rocuronium neuromuscular blocks considerably faster than neostigmine reversed moderate neuromuscular blocks. However, times to extubation did not differ significantly, apparently because extubation was largely determined by the time required for awaking from general anesthesia and because clinicians were willing to extubate before full neuromuscular recovery. Sugammadex may nonetheless be preferable to procedures that require a deep neuromuscular block and rapid recovery.

Effects of neuromuscular blocking agents on the clinical performance of i-gel® and surgical condition in elderly patients undergoing hand surgery: a prospective randomized controlled trial.

Background: The effects of neuromuscular blocking agents on the clinical performance of supraglottic airway devices and surgical condition in elderly patients undergoing hand surgery have not been established. We evaluated the effects of rocuronium on the clinical performance of an i-gel® supraglottic device and surgical condition in elderly patients undergoing orthopedic hand surgery. Methods: Patients aged 65-85 years were randomized to receive either rocuronium (rocuronium group) or saline (control group). We compared the rates of successful insertion of the i-gel on the first attempt as a primary outcome and also assessed the adequacy of i-gel maintenance during controlled ventilation, anesthetic requirement, surgical condition, and recovery time. Results: The rates of successful insertion of the i-gel on a first attempt were 93.1% in the rocuronium group versus 82.1% in the control group (P = 0.423). Peak inspiratory pressure (PIP) was lower in the rocuronium group than in the control group (15.2 vs. 17.9 cmH2O, respectively, P = 0.028). Spontaneous breathing was less common in the rocuronium group (24.1% vs. 57.1%, respectively, P = 0.011). The requirement of additional fentanyl to suppress spontaneous breathing or patient movement was less in the rocuronium group than in the control group (24.1% vs. 50.0%, respectively, P = 0.043). Surgical condition did not differ between the two groups. Recovery time was shorter in the rocuronium group than in the control group (8.4 vs. 9.9 min, respectively, P = 0.030). Conclusions: Rocuronium did not enhance the success rate of inserting the i-gel® or the surgical condition in elderly patients. However, using rocuronium reduced PIP, the frequency of spontaneous breathing, the requirement for additional fentanyl and patients' recovery time.

Low-Dose of Rocuronium During Thyroid Surgery: Effects on Intraoperative Nerve-Monitoring and Intubation.

BACKGROUND: Intraoperative Neurophysiological Monitoring (IONM) reduces the incidence of Recurrent Laryngeal Nerve (RLN) injuries during thyroid surgery. To preserve nerve function, long acting neuromuscular blocking agents (NMBA) should be avoided. However, NMBA are necessary for laryngoscopy and endotracheal intubation. We designed this double-blinded, randomized, placebo-controlled trial to assess if a low-dose of rocuronium given at intubation would affect the IONM data recorded before the thyroid dissection. METHODS: Hundred patients undergoing elective thyroid surgery were randomized to receive either 0.3 mg kg-1 of low dose rocuronium (intervention) or no-NMBA (control). Intubation was performed with video-laryngoscopy. IONM was placed on RLN and nerve stimulation was performed before and after thyroid dissection. The presence of a valid amplitude prior to dissection was defined when the IONM signal was >100 µV. Occurrence of difficult laryngoscopy was reported together with intubation details including time, difficulty and failure. The lowest peripheral saturation (SpO2) and the number of desaturation episodes during the intubation were also registered. RESULTS: No patients showed impaired IONM signal before dissection in both groups. Cormack-Lehane grade was higher in the intervention group (11;2) compared to control one (11;1; P = 0.046). No-NMBA patients had increased number of difficult laryngoscopies (21% versus 6%, P = 0.041) and intubations (34% versus 8%; P = 0.003) as well as a longer time to intubation (78 [55; 175] versus 55 [31; 110] sec; P = 0.006). Lower values of peripheral SpO2 during intubation attempt were registered in the no NMBA group (99 [97; 100] versus 99 [99; 100] %; P = 0.020). However, the number of intubation failure was similar between groups (p=0.495). CONCLUSIONS: Low-dose of rocuronium does not compromise pre-dissection IONM signal and improves intubation condition when compared to a relaxant free strategy.

First genome-wide association study on rocuronium dose requirements shows association with SLCO1A2.

BACKGROUND: Rocuronium, a common neuromuscular blocking agent, is mainly excreted unchanged in urine (10-25%) and bile (>70%). Age, sex, liver blood flow, smoking, medical conditions, and ethnic background can affect its pharmacological actions. However, reasons for the wide variation in rocuronium requirements are mostly unknown. We hypothesised that pharmacogenetic factors might explain part of the variation. METHODS: One thousand women undergoing surgery for breast cancer were studied. Anaesthesia was maintained with propofol (50-100 µg kg-1 min-1) and remifentanil (0.05-0.25 µg kg-1 min-1). Neuromuscular block was maintained with rocuronium to keep the train-of-four ratio at 0-10%. DNA was extracted from peripheral blood and genotyped with a next-generation genotyping array. The genome-wide association study (GWAS) was conducted using an additive linear regression model with PLINK software. The FINEMAP tool and data from the Genotype-Tissue Expression project v8 were utilised to study the locus further. RESULTS: The final patient population comprised 918 individuals. Of the clinical variables tested, age, BMI, ASA physical status, and total dose of propofol correlated significantly (all P<0.001) with the rocuronium dose in a linear regression model. The GWAS highlighted one genome-wide significant locus in chromosome 12. The single-nucleotide polymorphisms (SNPs) with the most significant evidence of association were located in or near SLCO1A2. The two top SNPs, rs7967354 (P=5.3e-11) and rs11045995 (P=1.4e-10), and the clinical variables accounted for 41% of the variability in rocuronium dosage. CONCLUSIONS: Genetic variation in the gene SLCO1A2, encoding OATP1A2, an uptake transporter, accounted for 4% of the variability in rocuronium consumption. The underlying mechanism remains unknown.