Coadministration of intravenous calcium along with neostigmine for rapid neuromuscular blockade recovery: A systematic review and meta-analysis.

Postoperative residual curarization (PORC) and the impact of the coadministration of intravenous calcium along with an acetylcholinesterase inhibitor on it are not well addressed. Extensive electronic database screening was done until October 7, 2022 after enlisting the protocol of this systematic review in PROSPERO (CRD42021274879). Randomized controlled trials (RCTs) evaluating the impact of intravenous calcium and neostigmine coadministration on neuromuscular recovery were included in this meta-analysis. Our search retrieved four RCTs with a total of 266 patients. The application of calcium shortened the neuromuscular recovery time (SMD = -2.13, 95% confidence interval [CI]: -2.66 to -1.59, I2 = 66%) and reduced the risk of PORC at 5 min (odds ratio [OR] = 0.21, 95% CI: 0.10-0.46, I2 = 0%), with an improved train-of-four (TOF) ratio at 5 min (mean difference [MD] = 9.28, 95% CI: 4-14.57, I2 = 66%). However, neither significant reduction in PORC at 10 min (OR = 0.41, 95% CI: 0.15-1.09, I2 = 0%) nor a better TOF ratio was associated with coadministration of calcium (MD = 0.40, 95% CI: -1.3-2.11). Coadministration of calcium along with neostigmine during the early period of neuromuscular blockade reversal can be used to enhance neuromuscular recovery.

Diaphragm ultrasonography as a monitor in assessing antagonistic effect of sugammadex on rocuronium in patients with Child-Pugh grades A and B.

Background: Although diaphragm ultrasound can be used for detecting residual neuromuscular blockade post-surgery, there exists notable dearth in contemporary research exploring the correlation between preoperative Child-Pugh classification and the effectiveness of sugammadex in reversing rocuronium-induced blockade as evaluated by diaphragmatic ultrasonography. Methods: This was a prospective, double-blind, non-randomized controlled clinical trial conducted on patients scheduled for laparoscopic liver resection surgery. The participants were categorized into two groups, A and B, based on their preoperative Child-Pugh classification. Prior to anesthesia induction, baseline diaphragm thickness was evaluated using ultrasonography. Throughout the surgical procedure, a deep neuromuscular blockade was maintained with rocuronium. Post-surgery, sugammadex (2 mg/kg) was intravenously administered to patients in both groups upon reaching a train-of-four ratio of 0.2. Diaphragm thickness was assessed at 0, 10, and 30 min, as well as 2 h after extubation, to analyze thickening fractioning (TF) and thickness recovery fractioning (TRF). Results: No significant differences in TF or TRF were observed between the two groups at 0, 10, and 30 min, as well as 2 h after extubation. Furthermore, there were no significant variances in hemodynamic stability following sugammadex administration. However, patients in the Child-Pugh B group experienced a significantly prolonged time from sugammadex administration to tracheal extubation (19 ± 8.0 min vs. 11 ± 6.1 min) and an extended post-anesthesia care unit stay (123 ± 28.3 min vs. 103 ± 26.0 min) compared to those in the Child-Pugh A group. Conclusion: The preoperative Child-Pugh grades may not exhibit a significant association with the reversal effect of sugammadex on rocuronium, as evaluated through diaphragmatic ultrasonography. Clinical trial registration: Registered in the ClinicalTrials.gov (NCT05028088) on July 18, 2021.

Recurarization with magnesium sulfate administered after two minutes sugammadex reversal: A randomized, double-blind, controlled trial.

STUDY OBJECTIVE: The current study tested the hypothesis that magnesium sulfate after reversal with sugammadex causes recurarization. DESIGN: A single-center, prospective, randomized, double-blind, controlled trial. SETTING: Terciary care hospital in Rio de Janeiro, Brazil. PATIENTS: Included 60 patients undergoing for elective otolaryngological surgery. INTERVENTIONS: All patients received total intravenous anesthesia and a single dose of rocuronium (0.6 mg/kg). In 30 patients, the neuromuscular blockade was reversed with sugammadex (4 mg/kg) at the reappearance of one or two posttetanic counts (deep-blockade series). In 30 other patients, sugammadex (2 mg/kg) was administered at the reappearance of the second twitch of the train-of-four (moderate-blockade series). After the normalized train-of-four ratio recovered to ≥0.9, the patients in each series were randomized to receive intravenous magnesium sulfate (60 mg/kg) or placebo for 10 min. Neuromuscular function was measured by acceleromyography. MEASUREMENTS: The primary outcome was the number of patients who exhibited recurarization (normalized train-of-four ratio < 0.9). The secondary outcome was rescue with an additional dose of sugammadex after 60 min. MAIN RESULTS: In the deep-blockade series, a normalized train-of-four ratio < 0.9 occurred in 9/14 (64%) patients receiving magnesium sulfate and 1/14 (7%) receiving placebo, RR 9.0 (95% CI: 62-1.30), and (p = 0.002), with four rescues with sugammadex. In the moderate-blockade series, neuromuscular blockade recurred in 11/15 (73%) patients receiving magnesium sulfate and in 0/14 (0%) receiving placebo (p < 0.001), with two rescues. The absolute differences in recurarization were 57% and 73% in the deep-blockade and moderate-blockade, respectively. CONCLUSIONS: Single-dose magnesium sulfate led to a normalized train-of-four ratio < 0.9, 2 min after recovery from rocuronium-induced deep and moderate neuromuscular blockade using sugammadex. Additional sugammadex reversed prolonged recurarization.

Comparison of the effects of neostigmine and sugammadex on postoperative residual curarization and postoperative pulmonary complications by means of diaphragm and lung ultrasonography: a study protocol for prospective double-blind randomized controlled trial.

BACKGROUND: Postoperative residual curarization (PORC) may be a potential risk factor of postoperative pulmonary complications (PPCs), and both of them will lead to adverse consequences on surgical patient recovery. The train-of-four ratio (TOFr) which is detected by acceleromyography of the adductor pollicis is thought as the gold standard for the measurement of PORC. However, diaphragm function recovery may differ from that of the peripheral muscles. Recent studies suggested that diaphragm ultrasonography may be useful to reveal the diaphragm function recovery, and similarly, lung ultrasound was reported for the assessment of PPCs in recent years as well. Sugammadex reversal of neuromuscular blockade is rapid and complete, and there appear to be fewer postoperative complications than with neostigmine. This study aims to compare the effects of neostigmine and sugammadex, on PORC and PPCs employing diaphragm and lung ultrasonography, respectively. METHODS/DESIGN: In this prospective, double-blind, randomized controlled trial, patients of the American Society of Anesthesiologists Physical Status I-III, aged over 60, will be enrolled. They will be scheduled to undergo arthroplasty under general anesthesia. All patients will be allocated randomly into two groups, group NEO (neostigmine) and group SUG (sugammadex), using these two drugs for reversing rocuronium. The primary outcome of the study is the incidence of PPCs in the NEO and SUG groups. The secondary outcomes are the evaluation of diaphragm ultrasonography and lung ultrasound, performed by an independent sonographer before anesthesia, and at 10 min and 30 min after extubation in the post-anesthesia care unit, respectively. DISCUSSION: Elimination of PORC is a priority at the emergence of anesthesia, and it may be associated with reducing postoperative complications like PPCs. Sugammadex was reported to be superior to reverse neuromuscular blockade than neostigmine. Theoretically, complete recovery of neuromuscular function should be indicated by TOFr > 0.9. However, the diaphragm function recovery may not be the same matter, which probably harms pulmonary function. The hypothesis will be proposed that sugammadex is more beneficial than neostigmine to reduce the incidence of PPCs and strongly favorable for the recovery of diaphragm function in our study setting. TRIAL REGISTRATION: ClinicalTrials.gov NCT05040490 . Registered on 3 September 2021.

Exploratory Outlier Detection for Acceleromyographic Neuromuscular Monitoring: Machine Learning Approach.

BACKGROUND: Perioperative quantitative monitoring of neuromuscular function in patients receiving neuromuscular blockers has become internationally recognized as an absolute and core necessity in modern anesthesia care. Because of their kinetic nature, artifactual recordings of acceleromyography-based neuromuscular monitoring devices are not unusual. These generate a great deal of cynicism among anesthesiologists, constituting an obstacle toward their widespread adoption. Through outlier analysis techniques, monitoring devices can learn to detect and flag signal abnormalities. Outlier analysis (or anomaly detection) refers to the problem of finding patterns in data that do not conform to expected behavior. OBJECTIVE: This study was motivated by the development of a smartphone app intended for neuromuscular monitoring based on combined accelerometric and angular hand movement data. During the paired comparison stage of this app against existing acceleromyography monitoring devices, it was noted that the results from both devices did not always concur. This study aims to engineer a set of features that enable the detection of outliers in the form of erroneous train-of-four (TOF) measurements from an acceleromyographic-based device. These features are tested for their potential in the detection of erroneous TOF measurements by developing an outlier detection algorithm. METHODS: A data set encompassing 533 high-sensitivity TOF measurements from 35 patients was created based on a multicentric open label trial of a purpose-built accelero- and gyroscopic-based neuromuscular monitoring app. A basic set of features was extracted based on raw data while a second set of features was purpose engineered based on TOF pattern characteristics. Two cost-sensitive logistic regression (CSLR) models were deployed to evaluate the performance of these features. The final output of the developed models was a binary classification, indicating if a TOF measurement was an outlier or not. RESULTS: A total of 7 basic features were extracted based on raw data, while another 8 features were engineered based on TOF pattern characteristics. The model training and testing were based on separate data sets: one with 319 measurements (18 outliers) and a second with 214 measurements (12 outliers). The F1 score (95% CI) was 0.86 (0.48-0.97) for the CSLR model with engineered features, significantly larger than the CSLR model with the basic features (0.29 [0.17-0.53]; P<.001). CONCLUSIONS: The set of engineered features and their corresponding incorporation in an outlier detection algorithm have the potential to increase overall neuromuscular monitoring data consistency. Integrating outlier flagging algorithms within neuromuscular monitors could potentially reduce overall acceleromyography-based reliability issues. TRIAL REGISTRATION: ClinicalTrials.gov NCT03605225; https://clinicaltrials.gov/ct2/show/NCT03605225.

Comparison of neuromuscular blockade recovery co-administered with neostigmine and different doses of calcium gluconate: a randomized control trial.

BACKGROUND: Calcium increases the probability of transmitter release at the neuromuscular junction. It is not known whether there is a dose-dependent relationship between the dosage of calcium gluconate and the probability of transmitter release for non-depolarizing neuromuscular blockade (NMB) recovery by acetylcholinesterase inhibitors (AchEIs). This study compared the neuromuscular recovery time and the incidence of postoperative residual curarization (PORC) according to the dosage of calcium gluconate co-administered with neostigmine in three patient groups. METHODS: Patients were randomly allocated to a control group, a 5 mg/kg calcium gluconate group (calcium 5 group), or a 10 mg/kg calcium gluconate group (calcium 10 group). In patients with a TOF ratio (TOFr) between 0.2-0.7, 0.04 mg/kg of neostigmine was administered and both 0.2 mg of glycopyrrolate and 0.4 mg of atropine per 1 mg of neostigmine were administered. And additional 5 or 10 mg/kg of calcium gluconate were administrated to the calcium 5 and 10 groups. The primary endpoint was neuromuscular recovery time (the time between reversal and TOFr≥0.9). The secondary endpoints were the incidence of PORC at 5, 10, and 20 min after reversal administration and the train-of-four ratio (TOFr) at each time point. RESULTS: The neuromuscular recovery time was 5.3 min in the control group, 3.9 min in the calcium 5 group, and 4.1 min in the calcium 10 group, respectively (P = 0.004). The incidence of PORC at 5 min after neostigmine administration was 12 in the control group, 4 in the calcium 5 group, and 4 in the calcium 10 group, respectively, with statistical significance (P = 0.014). CONCLUSIONS: The co-administration of calcium gluconate with neostigmine safely promoted early NMB recovery, and the neuromuscular recovery time of the calcium 10 group tended to be more evenly distributed than that of the calcium 5 group. TRIAL REGISTRATION: https://cris.nih.go.kr/cris/index.jsp(KCT0004182 ). Date of registration: August 122,019.

Use of protocol and evaluation of postoperative residual curarization incidence in the absence of intraoperative acceleromyography - Randomized clinical trial / Aplicação de protocolo e avaliação da incidência de curarização residual pós-operatória na ausência de aceleromiografia intraoperatória - Ensaio clínico randomizado

Abstract Objective Evaluate the incidence of postoperative residual curarization (PORC) in the post-anesthesia care unit (PACU) after the use of protocol and absence of intraoperative acceleromyography (AMG). Methods Randomized clinical trial with 122 patients allocated into two groups (protocol and control). Protocol group received initial and additional doses of rocuronium (0.6 mg·kg-1 and 10 mg, respectively); the use of rocuronium was avoided in the final 45 min; blockade reversal with neostigmine (50 µg·kg-1); time ≥15 min between reversion and extubation. Control: initial and additional doses of rocuronium, blockade reversal, neostigmine dose, and extubation time, all at the discretion of the anesthesiologist. AMG was used in the PACU and PORC considered at T4/T1 ratio <1.0. Results The incidence of PORC was lower in protocol group than in control group (25% vs. 45.2%, p = 0.02). In control group, total dose of rocuronium was higher in patients with PORC than without PORC (0.43 vs. 0.35 mg·kg-1·h-1, p = 0.03) and the time interval between the last administration of rocuronium and neostigmine was lower (75.0 vs. 101.0 min, p < 0.01). In protocol group, there was no difference regarding the analyzed parameters (with PORC vs. without PORC). Considering the entire study population and the presence or absence of PORC, total dose of rocuronium was higher in patients with PORC (0.42 vs. 0.31 mg·kg-1·h-1, p = 0.01), while the time interval between the last administration of rocuronium and neostigmine was lower (72.5 vs. 99.0 min, p ≤ 0.01). Conclusion The proposed systematization reduced PORC incidence in PACU in the absence of intraoperative AMG.

Resumo Objetivo Avaliou-se a incidência de curarização residual pós-operatória (CRPO) na sala de recuperação pós-anestésica (SRPA) após emprego de protocolo e ausência de aceleromiografia (AMG) intraoperatória. Métodos Ensaio clínico, aleatório, com 122 pacientes, distribuídas em dois grupos: protocolo e controle. Protocolo: dose inicial e adicionais de rocurônio foram de 0,6 mg.kg-1 e 10 mg, respectivamente; evitou-se o uso de rocurônio nos 45 minutos finais; reversão do bloqueio com neostigmina (50 µg.kg-1); tempo ≥ 15 minutos entre reversão e extubação. Controle: doses inicial e adicional de rocurônio, reversão do bloqueio, dose de neostigmina e momento da extubação decididos pelo anestesiologista. Foi usada AMG na SRPA e considerado CRPO razão T4/T1 < 1,0. Resultados A incidência de CRPO foi menor no grupo protocolo em relação ao controle (25% vs. 45,2%; p = 0,02). No grupo controle, a dose total de rocurônio foi maior em pacientes com CRPO em relação àqueles sem CRPO (0,43 vs. 0,35 mg.kg-1.h-1; p = 0,03) e o intervalo entre a última administração de rocurônio e a neostigmina foi menor (75,0 vs. 101,0 min; p < 0,01). No grupo protocolo não houve diferença dos parâmetros analisados (com CRPO vs. sem CRPO). Considerando toda a população de estudo e a presença ou não de CRPO, a dose total de rocurônio foi maior em pacientes com CRPO (0,42 vs. 0,31 mg.kg-1.h-1; p = 0,01), enquanto o intervalo entre a última administração de rocurônio e a neostigmina foi menor (72,5 vs. 99,0 min; p ≤ 0,01). Conclusão A sistematização proposta reduziu a incidência de CRPO na SRPA na ausência de AMG intraoperatória.

Development of an algorithm using clinical tests to avoid post-operative residual neuromuscular block.

BACKGROUND: Quantitative neuromuscular monitoring is the gold standard to detect postoperative residual curarization (PORC). Many anesthesiologists, however, use insensitive, qualitative neuromuscular monitoring or unreliable, clinical tests. Goal of this multicentre, prospective, double-blinded, assessor controlled study was to develop an algorithm of muscle function tests to identify PORC. METHODS: After extubation a blinded anesthetist performed eight clinical tests in 165 patients. Test results were correlated to calibrated electromyography train-of-four (TOF) ratio and to a postoperatively applied uncalibrated acceleromyography. A classification and regression tree (CART) was calculated developing the algorithm to identify PORC. This was validated against uncalibrated acceleromyography and tactile judgement of TOF fading in separate 100 patients. RESULTS: After eliminating three tests with poor correlation, a model with four tests (r = 0.844) and uncalibrated acceleromyography (r = 0.873) were correlated to electromyographical TOF-values without losing quality of prediction. CART analysis showed that three consecutively performed tests (arm lift, head lift and swallowing or eye opening) can predict electromyographical TOF. Prediction coefficients reveal an advantage of the uncalibrated acceleromyography in terms of specificity to identify the EMG measured train-of-four ratio < 0.7 (100% vs. 42.9%) and <0.9 (89.7% vs. 34.5%) compared to the algorithm. However, due to the high sensitivity of the algorithm (100% vs. 94.4%), the risk to overlook an awake patient with a train-of-four ratio < 0.7 was minimal. Tactile judgement of TOF fading showed poorest sensitivity and specifity at train of four ratio < 0.9 (33.7%, 0%) and <0.7 (18.8%, 16.7%). CONCLUSIONS: Residual neuromuscular blockade can be detected by uncalibrated acceleromyography and if not available by a pathway of four clinical muscle function tests in awake patients. The algorithm has a discriminative power comparable to uncalibrated AMG within TOF-values >0.7 and <0.3. TRIAL REGISTRATION: Clinical Trials.gov (principal investigator's name: CU, and identifier: NCT03219138) on July 8, 2017.

[Use of protocol and evaluation of postoperative residual curarization incidence in the absence of intraoperative acceleromyography - Randomized clinical trial]. / Aplicação de protocolo e avaliação da incidência de curarização residual pós­operatória na ausência de aceleromiografia intraoperatória ­ Ensaio clínico randomizado.

OBJECTIVE: Evaluate the incidence of postoperative residual curarization (PORC) in the post-anesthesia care unit (PACU) after the use of protocol and absence of intraoperative acceleromyography (AMG). METHODS: Randomized clinical trial with 122 patients allocated into two groups (protocol and control). Protocol group received initial and additional doses of rocuronium (0.6mg.kg-1 and 10mg, respectively); the use of rocuronium was avoided in the final 45minutes; blockade reversal with neostigmine (50µg.kg-1); time ≥ 15minutes between reversion and extubation. CONTROL: initial and additional doses of rocuronium, blockade reversal, neostigmine dose, and extubation time, all at the discretion of the anesthesiologist. AMG was used in the PACU and PORC considered at T4/T1 ratio<1.0. RESULTS: The incidence of PORC was lower in protocol group than in control group (25% vs. 45.2%, p=0.02). In control group, total dose of rocuronium was higher in patients with PORC than without PORC (0.43 vs. 0.35mg.kg-1.h-1, p=0.03) and the time interval between the last administration of rocuronium and neostigmine was lower (75.0 vs. 101.0min, p<0.01). In protocol group, there was no difference regarding the analyzed parameters (with PORC vs. without PORC). Considering the entire study population and the presence or absence of PORC, total dose of rocuronium was higher in patients with PORC (0.42 vs. 0.31mg.kg-1.h-1, p=0.01), while the time interval between the last administration of rocuronium and neostigmine was lower (72.5 vs. 99.0min, p ≤ 0.01). CONCLUSION: The proposed systematization reduced PORC incidence in PACU in the absence of intraoperative AMG.

What anesthesiologists ask to know and should know about the neuromuscular monitoring: an updated review

The increase in mortality and morbidity associated with the use of muscle relaxants, is associated with a lack of clinical pharmacological knowledge of the drugs, and a lack of understanding the risk of postoperative residual curarization. This is due to the absence of standards for neuromuscular monitoring. Clinicians experienced in neuromuscular monitoring and using muscle relaxants in the clinic may have some queries regarding the monitoring: Why should neuromuscular monitoring be done? Are clinical tests really not effective? Why is it not good when I actually perform neuromuscular monitoring? Would using sugammadex not require neuromuscular monitoring? This review answers most of the questions that many clinicians have, and also forwards the knowledge required of clinicians.

Neuromuscular blockade in the elderly.

The aim of the presented review is to highlight the clinical problem of postoperative residual curarization (PORC) following general anaesthesia in the elderly. Possible complications of PORC are described along with age-induced changes in pharmacokinetics of long and intermediate-acting neuromuscular blocking agents. This is intended to facilitate the selection and to promote appropriate intraoperative use of muscle relaxants in patients over the age of 65 years.

A Comparision of the Effect of Sugammadex on the Recovery Period and Postoperative Residual Block in Young Elderly and Middle-Aged Elderly Patients.

BACKGROUND: The importance of the characteristics of anesthesia and postoperative residual curarization (PORC) in the elderly population should be a growing concern in this century. AIMS: To investigate the effect of sugammadex on the duration of the recovery from neuromuscular blocking agents and postoperative residual curarization in the young elderly and middle-aged elderly patients who underwent elective laparoscopic cholecystectomy, followed by a train of four (TOF) watch monitorization. STUDY DESIGN: Prospective clinical trial study. METHODS: Sixty patients over the age of 65 with American Society of Anesthesiologists I-III were divided into two groups according to their age (65-74 years old and ≥75 years old). Patients received sugammadex (2.0 mg/kg iv) at the reappearance of the second twitch of the TOF as an agent for reversal of neuromuscular blockage at the end of surgery. Patients were extubated at the time of TOF ≥0.9. The patients' TOF responses were evaluated with regards to PORC in at the 5th minute and were followed up for one hour in the recovery room. Reintubation was applied for those patients who developed PORC and had peripheric oxygen saturation <90% despite being given 6 L oxygen per min with a face mask. RESULTS: The onset time of neuromuscular blocking agent and time from T2 to achieve TOF ratio 90% (the duration of sugammadex effect) or over were found to be longer in the middle-aged elderly group than in the young elderly group. A statistically significant relationship was found between age and the duration of TOF ratio to reach 0.9 in the same direction. The PORC incidence and rate of reintubation were found to be 1.7% in all patients. CONCLUSION: In our opinion, it is necessary to remember that the duration of sugammadex effect on the recovery period is prolonged for patients who are aged ≥75 years compared to patients aged between 65-74 years. (ClinicalTrials.gov Identifier: ACTRN12615000758505).

Sugammadex for reversal of neuromuscular blockade: a retrospective analysis of clinical outcomes and cost-effectiveness in a single center.

OBJECTIVE: The aim of the study is to evaluate the clinical and economic impact of introducing a rocuronium-neostigmine-sugammadex strategy into a cisatracurium-neostigmine regimen for neuromuscular block (NMB) management. METHODS: We conducted a retrospective analysis of clinical outcomes and cost-effectiveness in five operating rooms at University Hospital of Padova. A clinical outcome evaluation after sugammadex administration as first-choice reversal drug in selected patients (rocuronium-sugammadex) and as rescue therapy after neostigmine reversal (rocuronium-neostigmine-sugammadex) compared to control was performed. A cost-analysis of NMB management accompanying the introduction of a rocuronium-neostigmine-sugammadex strategy into a cisatracurium-neostigmine regimen was carried out. To such purpose, two periods were compared: 2011-2012, without sugammadex available; 2013-2014, with sugammadex available. A subsequent analysis was performed to evaluate if sugammadex replacing neostigmine as first choice reversal drug is cost-effective. RESULTS: The introduction of a rocuronium-neostigmine-sugammadex strategy into a cisatracurium-neostigmine regimen reduced the average cost of NMB management by 36%, from €20.8/case to €13.3/case. Patients receiving sugammadex as a first-choice reversal drug (3%) exhibited significantly better train-of-four ratios at extubation (P<0.001) and were discharged to the surgical ward (P<0.001) more rapidly than controls. The cost-saving of sugammadex as first-choice reversal drug has been estimated to be €2.9/case. Patients receiving sugammadex as rescue therapy after neostigmine reversal (3.2%) showed no difference in time to discharge to the surgical ward (P=0.44) compared to controls. No unplanned intensive care unit (ICU) admissions with rocuronium-neostigmine-sugammadex strategy were observed. The potential economic benefit in avoiding postoperative residual curarization (PORC)-related ICU admission in the 2013-2014 period was estimated at an average value of €13,548 (€9,316-€23,845). CONCLUSION: Sugammadex eliminated PORC and associated morbidities. In our center, sugammadex reduced the costs of NMB management and promoted rapid turnover of patients in operating rooms, with total cost-effectiveness that counteracts the disadvantages of its high cost.

Incidence and risk factors of postoperative residual curarization in patients with breast cancer: Prospective cohort study / 解放军医学杂志

Objective To determine the incidence and risk factors of postoperative residual curarization (PORC) in patients with breast cancer after total intravenous anesthesia (TIVA) with vecuronium. Methods Two hundred and fiftyseven female patients with breast cancer undergoing breast-cancer surgery were enrolled into the present study. Anesthesia was induced with target-controlled infusion of propofol (Cp 3-4µg/ml) and remifentanil (2-3 ng/ml). A bolus of vecuronium 0.1mg/ kg was administered intravenously over 5-10s as soon as the patient lost consciousness, and laryngeal mask was placed 3min later. Mechanical ventilation and TIVA were performed for maintaining anesthesia and keeping bispectral index (BIS) between 40 to 60 during the operation. According to the duration of operation, 0.02mg/kg of vecuronium was administrated intermittently. Extubation of the laryngeal tube was performed according to clinical criteria. Train-of-four ratios (TOFr) were immediately measured with Veryark-TOF (Guangzhou Weilifangzhou Technology Ltd, China) in the recovery room. The patients were divided into two groups (Group N and Group R) according to the value of TOFr at the time of extubation. N denoted the non-residual neuromuscular blockade group (TOF=0.7), and R denoted the residual neuromuscular blockade group (TOF0.05). In group R, age and hemoglobin level were lower (P0.05). More patients in Group R received neoadjuvant chemotherapy and multiple boluses of vecuronium administration, and the duration between last dose of vecuronium to extubation was also prolonged compared with Group N (P<0.05). Multivariate logistic regression analysis identified that age, neoadjuvant chemotherapy and multiple boluses of vecuronium administration were not associated with increased risk of PORC. Duration from last dose of vecuronium to extubation was associated with increased risk of PORC (OR=0.970, 95%CI 0.956-0.984, P<0.001). Conclusions PORC is commonly used in patients with breast cancer. Duration from last dose of vecuronium to extubation is associated with increased risk of PORC.

Comparison of recovery times from deep neuromuscular blockade between single bolus and continuous infusion of rocuronium

BACKGROUND: To prevent sudden unexpected movement of patients during surgery, muscle relaxants are used to maintain intense neuromuscular blockade.They are administered by intermittent bolus or continuous infusion.Rocuronium is often used for continuous infusion because it is known to lack cumulative effects. The purpose of this study was to compare recovery times from intense neuromuscular block to reappearance of muscle twitches after 0.1 Hz single twitch stimulation. MATERIALS AND METHODS: Seventy five patients were randomized to one of 3 groups.Patients in group 1 were administered a single bolus of rocuronium; groups 2 and 3 were given continuous infusion of rocuronium for 1 and 2 h, respectively.During anesthesia, neuromuscular blockade was monitored by TOF-watch(R) and regulated so as not to exceed more than 5 (PTC) during the infusion. After infusion, PTC was counted every 5 min until single twitch heights had reappeared and the time till the twitch reappeared was calculated. RESULTS: There was a good correlation between the time it took to observe a PTC and the first response of TOF time in each group.In a parallelism test, there were no significant differences. There were also no significant differences in recovery times from PTC to the reappearance of a single twitch between groups. CONCLUSIONS: There are no significant differences in recovery times-from deep neuromuscular blockade to reappearance of single twitch-regardless of the infusion time.When a PTC occurs during deep neuromuscular blockade, it may predict the remaining time of reappearance of a single twitch response.