Residual Neuromuscular Block Research Articles

Does the objective measurement of muscle strength improve the detection of postoperative residual muscle weakness?

The postoperative residual neuromuscular block (PRNB) has a significant impact on patient safety and well-being, but continues to remain underestimated. Objective evaluation of handgrip strength using a force dynamometer can be useful to identify postoperative muscle weakness. Thirty-two American Society of Anesthesiologists (ASA) class I and II patients who received general anesthesia were included. Patients were extubated after the train-of-four (TOR) ratio (TOFR) was >0.90 and the clinical criteria for motor power recovery were judged as adequate. The measurements of handgrip strength and peak expiratory flow rate (PEFR) were obtained at baseline, 15 min after extubation, and 1, 2, and 4 h postoperatively. The incidence of significant decline from baseline (>25%) was determined. The correlation between handgrip strength and PEFR was assessed using Spearman correlation. The time to return to baseline for muscle grip strength and PEFR was performed using Kaplan-Meier survival analysis. A P value of 0.05 was considered significant for all tests. The incidence of the significant decline in handgrip strength from baseline was 100% at 15 and 60 min, 76% at 2 h, and 9.4% at 4 h. There was a strong correlation between muscle grip strength and PEFR (0.89, P < 0.001). None of the patients exhibited the potential complications of PRNB. (PRMB in abstract. It should be uniform) The mean time to return to the baseline value of muscle grip strength was 3.8 h (95% confidence interval [CI] 3.6-3.9), and the mean time to return to baseline for PEFR was 3.2 h (95% CI 2.9-3.4 h). Objective assessment of muscle grip strength using a force dynamometer has the potential to be a new objective metric to monitor postoperative muscle weakness.

Dynamometer based hand grip strength as a clinical tool for objective assessment of post-operative residual muscle weakness.

Residual neuromuscular block continues to be a significant postoperative complication despite neuromuscular monitoring. This study aims to determine the applicability of a hand-held forced dynamometer for hand grip strength assessment as an objective measure of residual muscle weakness. The study included patients undergoing surgery under general anaesthesia. A demonstration was given to the patient on the usage of a dynamometer for handgrip strength and a peak expiratory flow meter for peak expiratory flow rate (PEFR) and baseline values were recorded. The parameters were monitored at 15 minutes post-extubation and again at intervals of 15 minutes until one hour, half-hourly until four hours, and hourly until six hours post-operatively. Paired t-test was used for comparison of baseline muscle strength and PEFR with the parameters at different time points. Association between muscle strength and PEFR was tested with the Pearson-correlation test. Muscle strength was 50 to 60%, 75% and 100% of baseline at 15, 45 and 210 minutes after extubation, respectively. PEFR was 50 to 60%, 75% and 100% of baseline at 15, 60 and 180 minutes after extubation. The Pearson-correlation test established a positive correlation between handgrip strength and PEFR (correlation-coefficient 0.86). A significant reduction in the postoperative muscle strength can be detected using an objective forced dynamometer to measure handgrip strength even when train of four count has returned to unity and even when there are no clinical signs of muscle weakness. The residual muscle weakness is significant enough to affect the PEFR in the postoperative period.

Comparison of the anesthetic effects of mivacurium and cisatracurium besylate in laser laryngeal microsurgery

Objective: To compare the anesthetic effects of mivacurium and cisatracurium besylate in laser laryngeal microsurgery, and to provide clinical evidence and reference for further optimization of muscle relaxation application. Methods: From October 2021 to January 2022, fifty-six patients of Beijing Tongren Hospital, Capital Medical University, scheduled for laser laryngeal microsurgery with general anesthesia, were enrolled. These patients, aged 18-65 years old, 25 males and 31 females, were divided into two groups (n=28) by random number table method. Cisatracurium besylate group (group C): cisatracurium besylate was injected at 0.1 mg/kg. Normal saline was continuously infused during operation. Mivacurium group (group M):Mivacurium was injected at 0.25 mg/kg and continuously infused at 0.3 mg·kg-1·h-1 during operation.The intubation time, the extubation time, recovery index, Cooper's score, Cormack-Lehane grade, surgical condition grade, postoperative residual neuromuscular block and allergic related adverse events were compared between the two groups. Results: The intubation time and the extubation time of group M were (3.7±1.1) and (16.2±5.0) min, which were statistically significant shorter than those of group C (4.9±0.7) and (26.4±8.6) min (all P<0.05). The recovery indexes of the patients in group M and group C were (4.5±3.4) and (6.2±5.0) min. The Cooper's scores of the two groups were both 9(9, 9). The Cormack-Lehane grades of the two groups were all grade Ⅰ. The number of cases with good/excellent surgical condition grades in group M and group C were 5/23 and 0/28. There were no significant differences in recovery index, Cooper's score, Cormack-Lehane grades and surgical condition grades between the two groups (all P>0.05). The TOF ratio of group M in the post anesthesia care unit (PACU) was (95.7±2.6) %, which was significantly higher than (92.9±3.9) % of group C(P=0.015). There were no significant differences in MAP and HR between the two groups at different time points (all P>0.05). The incidence of skin flushing in group M and group C was 10.7% (3/28) and 0, and the difference was not statistically significant (P=0.074). There were no cases of severe hypotension, significantly elevated airway pressure or airway spasm in both groups. Conclusion: In laser laryngeal microsurgery, compared with cisatracurium besylate, mivacurium has shorter intubation time and extubation time, stable hemodynamics, no significant increase in allergic related adverse events. mivacurium is safe and effective.

This Month in Anesthesiology

This Month in Anesthesiology

Choice of neuromuscular block reversal agent to reduce postoperative pulmonary complications.

The definition of postoperative pulmonary complications (PPCs) is inconsistent in literature; however, PPCs include pulmonary abnormalities that adversely affect patient outcomes, such as respiratory failure, atelectasis, pneumonia, pleural effusion, and exacerbation of underlying lung conditions. Furthermore, although the incidence of PPCs varies according to its definition, surgery type, and patient population, they can lead to increased morbidity, mortality, duration of hospitalization, and medical costs; thus, efforts to identify and reduce the risk factors are important to improve patient outcomes. Among the risk factors for PPCs, residual neuromuscular block is a representative and preventable anesthesia-related risk factor that is affected by the choice of the reversal agent. However, it is not clear whether the chosen reversal agent, i.e., sugammadex, reduces PPCs better when compared to anticholinesterases. Additionally, the effects of the reversal agents on PPCs in high-risk patients, such as elderly patients, pediatric patients, those with end-stage renal disease, obesity, obstructive sleep apnea, or those undergoing specific surgeries, are diverse. To reduce the PPCs associated with the use of neuromuscular blocking agents, it is important to confirm complete reversal of the neuromuscular block under neuromuscular monitoring. Additionally, efforts to reduce the incidence of PPCs through interdisciplinary communication are required.

Abstract No.: ABS3480 : Dynamometer based hand grip strength as a clinical tool for objective assessment of post-operative residual muscle weakness

Background and Aims:Residual neuromuscular block is a known postoperative complication. Even after train of four (TOF) ratio of >0.9, there is a possibility of neuromuscular blockade causing respiratory dysfunction. Primary objective was assessment of postoperative residual muscle weakness with dynamometer. Secondary objective was time of recovery to baseline strength.Methods:This was a single centre, prospective, observational study. We enroled 50 patients undergoing surgery under general anesthesia. The patients of Americal Society of Anesthesiologists physical status I-II, aged 18-60 years and undergoing surgery under general anaesthesia were included. The patients with surgery including fracture, deformity involving dominant upper limb and pre-existing neuromuscular diseases were excluded from the study. Baseline handgrip strength with dynamometer and peak expiratory flow rate (PEFR) were observed before induction of anaesthesia. Trachea was extubated with TOF ratio >0.9. Values monitored at 15 minutes after extubation,at regular intervals of 15 minutes until 1 hour, 30 minutes until 4 hours and hourly until 6 hours.Results:Muscle strength remained 50 to 60% of baseline at 15 minutes, 75% at 45 minutes and reached 100% of baseline at 210 minutes after endotracheal extubation. PEFR remained 50 - 60 % of baseline at 15minutes, 75% of baseline at 60 minutes and reached 100% of baseline at 180 minutes after endotracheal extubation (Table 1).Conclusion:A significant reduction in the postoperative muscle strength was detected using objective force dynamometer to measure handgrip strength even when TOF ratio had returned to 1 with no clinical signs of muscle weakness.Table 1Difference in peak expiratory flow rate (PEFR) as change from baseline to postoperatively up to 300 minTimePEFR (mean±standard deviation)Percentage of baseline (%) P Baseline234.82±78.3010015 min139.25±5259.300.00030 min150.75±53.3064.200.00045 min163.14±56.5069.500.00060 min174.85±58.4074.500.00090 min188.3±61.8080.200.000120 min208.63±61.8088.800.000150 min221.95±67.3094.500.000180 min233.30±73.6599.300.003210 min245.57±72.28105.000.043240 min236.78±72.50101.000.070300 min256.00±91.00109.000.400

Improving neuromuscular monitoring and reducing residual neuromuscular blockade via e-learning: A multicentre interrupted time-series study (INVERT study).

BackgroundNeuromuscular monitoring should be applied routinely to avoid residual neuromuscular block. However, anaesthetists often refrain from applying it, even when the equipment is available. We aimed to increase neuromuscular monitoring in six Danish anaesthesia departments via e‐learning.MethodsInterrupted time series study, with baseline data from a previous study and prospective data collection after implementation of the module, which was available for 2 weeks from 21 November 2016. We included all patients receiving general anaesthesia with muscle relaxants until 30 April 2017. Main outcome was application of acceleromyography, grouped as succinylcholine only and non‐depolarising relaxants. Secondary outcomes were last recorded train‐of‐four ratio (non‐depolarising) relaxants and score on a ten‐question pre‐ and post‐course multiple‐choice test.ResultsThe post‐intervention data consisted of 6525 cases (3099 (48%) succinylcholine only, 3426 (52%) non‐depolarising relaxants). Analysing all departments, we found a positive pre‐intervention trend in application of acceleromyography for both groups, of estimated 7.5% and 4.8% per year, respectively (p < .001). The monitoring rate increased significantly for succinylcholine in two departments post‐intervention (p = .045 and .010), and for non‐depolarising relaxants in one department (p = .041), but followed by a negative trend of −37.0% per year (p = .041). The rate was already close to 90% at the time of the intervention and the mean last recorded train‐of‐four ratio was 0.97 (SD 0.21), also without a significant change. The median score on the post‐course test increased from 7 (IQR 5–8) to 9 (IQR 8–10) (p < .001, Wilcoxon Signed‐Ranks Test).ConclusionWe found no overall effect of the e‐learning module on application of neuromuscular monitoring, although the post‐course test indicated an effect on anaesthetists’ knowledge in this field.Trial registrationTrial registration: Clinicaltrials.gov identifier: NCT02925143. https://clinicaltrials.gov/ct2/show/NCT02925143

This Month in Anesthesiology

This Month in Anesthesiology

Residual neuromuscular block in the postanesthesia care unit: incidence, risk factors, and effect of neuromuscular monitoring and reversal agents.

The aim of this study was to determine the incidence of residual neuromuscular block (RNMB) in a tertiary care hospital. Secondary goals were to examine the characteristics of the use of intraoperative neuromuscular monitoring (NMM) and different reversal agents by the attending anesthesiologists, and to determine the factors related to the patient and perioperative processes on the development of RNMB. The patients' arrival time at the postanesthesia care unit was accepted as point zero (T0). The acceleromyography of the patients' adductor pollicis muscle was monitored for NMM. Train of four ratios (TOFRs) were recorded at 0, 10, 20, and 30 min. A TOFR < 0.9 was defined as RNMB. Patients' demographic and perioperative data were also recorded. A total of 216 patients completed the study. RNMB was observed in 47 patients (21.8%). Seventy-eight patients (36%) were followed up with NMM. Neostigmine and sugammadex were used in 174 (80.5%) and 42 (19.5%) patients, respectively, and they were both underdosed (21.2 ± 3.0 mcg/kg and 1.5 ± 0.7 mg/kg, respectively). Use of neostigmine and absence of NMM were risk factors for RNMB (p: 0.01 and 0.001, respectively) along with the number of additional doses (>1 doses, p ≤ 0.02) and the timing of the last dose of rocuronium (<88 min, p ≤ 0.01). None of the patients who received both NMM and sugammadex experienced RNMB. The RNMB incidence was found to be 21.8%. The main reasons of it were the lack of intraoperative NMM and inappropriate use of reversal agents. Despite strong recommendations, the use of NMM is still insufficient and reversal agents are still underdosed.

Quantitative Neuromuscular Monitoring and Postoperative Outcomes: A Narrative Review.

Over the past five decades, quantitative neuromuscular monitoring devices have been used to examine the incidence of postoperative residual neuromuscular block in international clinical practices, and to determine their role in reducing the risk of residual neuromuscular block and associated adverse clinical outcomes. Several clinical trials and a recent meta-analysis have documented that the intraoperative application of quantitative monitoring significantly reduces the risk of residual neuromuscular blockade in the operating room and postanesthesia care unit. In addition, emerging data show that quantitative monitoring minimizes the risk of adverse clinical events, such as unplanned postoperative reintubations, hypoxemia, and postoperative episodes of airway obstruction associated with incomplete neuromuscular recovery, and may improve postoperative respiratory outcomes. Several international anesthesia societies have recommended that quantitative monitoring be performed whenever a neuromuscular blocking agent is administered. Therefore, a comprehensive review of the literature was performed to determine the potential benefits of quantitative monitoring in the perioperative setting.

Efficacy of Palonosetron and Dexamethasone for Prevention of Post-operative Nausea and Vomiting in Female Patients Undergoing Laparoscopic Cholecystectomy: A Prospective Randomised Double-Blind Trial.

Post-operative nausea and vomiting is a frequent complication following anaesthesia. We compared the efficacy and safety of intravenous palonosetron and intravenous dexamethasone as prophylactic antiemetic in patients undergoing laparoscopic cholecystectomy. After obtaining institutional ethical committee approval, 100 adult female patients undergoing laparoscopic cholecystectomy were randomised to receive 4mg dexamethasone (group I, n ¼ 50) or 0.075 mg palonosetron (group II, n ¼ 50) intravenously (IV) over 2-5 minutes prior to induction of anaesthesia. Standard anaesthetic technique was followed, and the residual neuromuscular block was antagonised at theend of the procedure. A single anaesthesiologist assessed all the cases for post-operative nausea and vomiting (PONV) for 24 hours. The complete response rate and the overall patient satisfaction were noted. If patient experienced PONV, injection metoclopramide 10 mg was given as rescue antiemetic IV. A total of six patients had vomiting within 6 hours (four patients in groups I and two patients in group II), whereas none had vomiting after 6 hours (P ¼ .39). Complete response rate was 88 and 90% in both group I and group II. Three patients in both group I and group II required rescue antiemetics. Ninety-two percent patients were completely satisfied in group I, while 96% patients were fully satisfied in group II. Intravenous administration of palonosetron (0.075 mg) is as effective as dexamethasone (4 mg) as prophylactic antiemetic without any untoward side effects for female patients undergoing laparoscopic cholecystectomy.

Required dose of sugammadex or neostigmine for reversal of vecuronium-induced shallow residual neuromuscular block at a train-of-four ratio of 0.3.

Residual shallow neuromuscular block (NMB) is potentially harmful and contributes to critical respiratory events. Evidence for the optimal dose of sugammadex required to reverse vecuronium‐induced shallow NMB is scarce. The aims of the present study were to find suitable doses of sugammadex and neostigmine to reverse a residual vecuronium‐induced NMB from a time of flight (TOF) ratio of 0.3–0.9 and evaluate their safety and efficacy. In total, 121 patients aged 18–65 years were randomly assigned to 11 groups to receive placebo, sugammadex (doses of 0.125, 0.25, 0.5, 1.0, or 2.0 mg/kg), or neostigmine (doses of 10, 25, 40, 55, or 70 μg/kg). The reversal time of sugammadex and neostigmine to antagonize a vecuronium‐induced shallow residual NMB (i.e., TOF ratio of 0.3) and related adverse reactions were recorded. Several statistical models were tested to find an appropriate statistical model to explore the suitable doses of sugammadex and neostigmine required to reverse a residual vecuronium‐induced NMB. Based on a monoexponential model with the response variable on a logarithmic scale, sugammadex 0.56 mg/kg may be sufficient to reverse vecuronium‐induced shallow residual NMB at a TOF ratio of 0.3 under anesthesia maintained with propofol. Neostigmine may not provide prompt and satisfactory antagonism as sugammadex, even in shallow NMB.

Reversal of residual neuromuscular block with neostigmine or sugammadex and postoperative pulmonary complications: a prospective, randomised, double-blind trial in high-risk older patients

Reversal of residual neuromuscular block with neostigmine or sugammadex and postoperative pulmonary complications: a prospective, randomised, double-blind trial in high-risk older patients

Evaluation of the impact of deep neuromuscular blockade on surgical conditions for laryngeal microsurgery with High Frequency Jet Ventilation. A comparison with no block during intravenous general anesthesia with topical lidocaine

ObjectiveLaryngeal transoral surgery classically requires a neuromuscular block (NMB) to facilitate tracheal intubation and to improve surgical conditions. However, the short duration of most procedures and the potential complications of residual NMB lead to consider a no block approach. The hypothesis that intravenous anesthesia (remifentanil and propofol infusions) without NMB but including glottis topical lidocaine anesthesia would allow clinically acceptable laryngeal exposure and good surgical conditions was tested in the specific context of procedures undergone with High Frequency Jet Ventilation (HFJV). Study designA prospective randomized clinical comparison. Methods66 consenting patients were planned to receive 0.6 mg·kg−1 rocuronium or saline at random. The outcome measurements included the time and conditions to complete suspended laryngoscopy, and the surgical conditions rated by the surgeon. Any vocal cord movement or coughing was recorded. Data were compared using a Wilcoxon rank-sum test for numerical variables and chi-square test for categorical ones. Treatment failure was defined as an impossible laryngoscopy or a grade 4 surgical field occurring at any time during surgery and was compared to its null theoretical value by a general z-test. An interim analysis after completion of 50% patients was performed using Pocock boundaries at 0.0294 significance levels. ResultsA significant failure rate occurred in the non paralysed group (27%, p < 0.001). No coughing and no vocal cords movement occurred in the NMB group. Poorer surgical conditions were obtained without NMB (p = 0.011). ConclusionInducing a deep NMB ensured improved conditions during direct laryngeal microsurgery with HFJV.

Preoperative effects of magnesium sulfate on hemodynamics and muscle relaxation

Background/Aim: Although there are many studies on the effects of magnesium sulfate in the literature, there is no publication on the effects of low doses of magnesium sulfate, as we administered in our study. This prospective randomized study aimed to reveal that the use of low-dose magnesium sulfate (MgSO4) shortens the onset time and prolongs the block duration of neuromuscular blockers (NMBs) without changing the hemodynamics in patients monitored using the train-of-four (TOF) ratio. Methods: This is a prospective randomized study. A total of 60 cases aged between 18–65 years with American Society of Anesthesiologists classifications I–II who were scheduled for elective open cholecystectomy were randomly divided into 3 groups. Notably, 15 minutes before the anesthesia induction, 25 mg/kg MgSO4 in intravenous 0.9% saline (total volume, 100 mL) was administered to the MgSO4 group (MS group), 0.03 mg/kg midazolam was administered to the midazolam group (MD group), and the same volume of 0.9% saline solution was administered to the control group (PSS group). Nerve-muscle conduction monitoring was performed using TOF-Watch® SX (Organon, Ireland) and anesthesia depth was monitored with a BIS® monitor (A-2000; Aspect Medical Systems, USA). Results: NMB onset times were 83.95 (26.8), 111.15 (28.12), and 163.7 (34.16) seconds (P=0.001) in the MS, MD, and PSS groups, respectively. The times until additional rocuronium requirement after the intubation dose were 60.1 (4.19), 50.8 (4.99), and 38.25 (7.27) minutes in the MS, MD, and PSS groups, respectively, which was significantly longer in the MS group compared to the other groups (P 95% was longer in the MS group than in the other groups. No difference was found between the groups in terms of hemodynamic data. Conclusion: Low-dose MgSO4 administration before rocuronium injection significantly reduces neuromuscular agent consumption without altering hemodynamics and causing a residual neuromuscular block.

Quantitative Neuromuscular Monitoring With Train-of-Four Ratio During Elective Surgery: A Prospective, Observational Study.

Postoperative residual neuromuscular block (PRNB) is a serious problem that can cause death after surgery. It was aimed to evaluate the adequacy of neuromuscular block (NMB) during endotracheal intubation and the adequacy of neuromuscular recovery during clinically extubation decision and follow-up with the train-of-four ratio (TOFR) using quantitative monitoring. This study has a prospective-observational single-blind study design. A total of 205 adult patients who underwent elective surgery, who had American Society of Anesthesiologists physical statuses I to III, and who were intubated with neuromuscular blocking agent under general anesthesia were included in the study. Train-of-four ratio measurements were provided single-blindly by another anesthesiologist outside the team. The TOFRs were measured at the time of intubation (TOFRind), before reversal agent administration (TOFRpre-rev) and after (TOFRpost-rev), at the time of extubation (TOFRext), and on admission to the postoperative care unit (TOFRPACU). If clinical signs of PRNB appeared, the recovery protocol was applied and then TOFRrec was measured. Postoperative respiratory complications were also evaluated for the first 24 hours after surgery. Endotracheal intubation was performed in 41.5% of the patients (n = 85) without adequate NMB. In 48.8% (n = 100) of the patients, adequate recovery (TOFRext ˂0.9) was not available at the time of extubation. Adequate TOFRPACU rate was found to be significantly higher in those who did not receive additional neuromuscular blocking agent doses (P < 0.001). In the recovery protocol, low-dose sugammadex administered to patients with clinical signs of PRNB significantly increased the TOFRrec rate compared with neostigmine (P ˂ 0.001). The first 24 hours, postoperative respiratory complication rate was 5.4% (n = 11), and the most common hypoxemia was observed. Approximately half of the patients are intubated without sufficient NMB and extubated without sufficient neuromuscular recovery. This suggests that routine use of quantitative neuromuscular monitoring is necessary for patient safety.

100 Hz-5 s tetanic stimulation to illustrate the presence of “residual paralysis” co-existing with accelerometric 0.90 train-of-four ratio—A proof-of-concept study

BackgroundAn acceleromyographic train-of-four (TOF) ratio of 0.90 at extubation does not prevent postoperative pulmonary complications in surgical patients receiving non-depolarising muscle relaxants. This recent observation suggests that a more selective neuromuscular transmission monitoring parameter is mandatory to detect more precisely any remaining residual paralysis. The aim of our proof-of-concept study was to evaluate, in patients receiving rocuronium, the degree of 100-Hz, 5-s tetanic fade present when the acceleromyographic TOF ratio has recovered to 0.90. MethodsTwenty adult patients scheduled for surgery under general anaesthesia were included. Before anaesthesia induction, a TOF-Watch SX™ and a VISUAL-ITF© (a prototype monitor for recording isometric force) were positioned on both hands. After induction but before rocuronium injection, a 100-Hz, 5-s tetanus (TET0) was delivered to both ulnar nerves. Thereafter, TOF stimulations every 15 s were delivered to both arms until a TOF ratio > 0.90 was recorded; then, a 100-Hz, 5-s tetanus (TET1) was recorded on the VISUAL-ITF© monitor. The values of the tetanic parameters (force) recorded at TET0 and TET1 were compared using a Wilcoxon rank sum test. ResultsCompared to TET0, tetanic parameters of TET1 were significantly lower (median [range]): maximal force 36.4 [19.2−82.6] vs. 25.5 [5.0−42.4] Newton (p < 0.005); residual force 36.2 [18.2−82.0] vs. 5.5 [0.20–38.3] Newton (p < 0.0001) and residual force/maximal force ratio 0.98 [0.89−0.99] vs. 0.17 [0.03−0.90] (p < 0.0001). ConclusionOur results confirm that even when the acceleromyographic TOF ratios have recovered to above 0.90, the contralateral 100-Hz, 5-s tetanic stimulus may show tetanic fade characteristic of residual neuromuscular block, and may help improve the safety of tracheal extubation.

Reversal of residual neuromuscular block with neostigmine or sugammadex and postoperative pulmonary complications: a prospective, randomised, double-blind trial in high-risk older patients

BackgroundResidual neuromuscular block is associated with an increased risk of postoperative pulmonary complications in retrospective studies. The aim of our study was to investigate prospectively the incidence of postoperative pulmonary complications after reversal with either sugammadex (SUG) or neostigmine (NEO) in high-risk older patients. MethodsWe randomly allocated 180 older patients with significant morbidity (ASA physical status 3) ≥75 yr old to reversal of rocuronium with either SUG or NEO. Adverse events in the recovery room and pulmonary complications (defined by a 5-point [0–4; 0=best to 4=worst] outcome score) on postoperative Days 1, 3, and 7 were compared between groups. ResultsData from 168 patients aged 80 (4) yr were analysed; SUG vs NEO resulted in a reduced probability (0.052 vs 0.122) of increased pulmonary outcome score (impaired outcome) on postoperative Day 7, but not on Days 1 and 3. More patients in the NEO group were diagnosed with radiographically confirmed pneumonia (9.6% vs 2.4%; P=0.046). The NEO group showed a non-significant trend towards longer hospital length of stay across all individual centres (combined 9 vs 7.5 days), with a significant difference in Malaysia (6 vs 4 days; P=0.011). ConclusionsReversal of rocuronium neuromuscular block with SUG resulted in a small, but possibly clinically relevant improvement in pulmonary outcome in a select cohort of high-risk older patients. Clinical trial registrationACTRN12614000108617.

Extravascular leakage of induction doses of rocuronium: four cases in which both depth of neuromuscular block and plasma concentration of rocuronium were assessed.

The duration of action of extravasated rocuronium varies depending on the patient's comorbidities. In patients who receive high doses of non-depolarizing neuromuscular blocking agents subcutaneously, anesthesiologists should be aware of unexpected prolongation of the progress and recovery of neuromuscular block. In such cases, the depth and recovery of neuromuscular block should be objectively monitored to avoid residual neuromuscular block and recurarization.

Unanticipated Consequences of Switching to Sugammadex: Anesthesia Provider Survey on the Hormone Contraceptive Drug Interaction.

Sugammadex binds progesterone with high affinity and may interfere with hormonal contraceptive effectiveness. The clinical, economical, and ethical implications of unintended pregnancy should prompt anesthesiologists to actively consider and manage this pharmacologic interaction. We surveyed anesthesiology providers at our institution about knowledge of this potential adverse drug interaction, how they manage it clinically, and the extent to which they involve patients in shared decision-making regarding choice of neuromuscular blocker antagonist. A survey instrument was distributed to anesthesiology providers at a large, tertiary-care medical center. The survey explored prior experience using neostigmine and sugammadex, knowledge about potential sugammadex interference with hormonal contraception, pre-/postoperative counseling practices, clinical management, and shared decision-making regarding potential use of neostigmine in lieu of sugammadex to avoid this drug-drug interaction. Of 259 surveys distributed, 155 were fully completed, and 10 were partially completed. Overall response rate was 60% (residents 85%, student nurse anesthetists 53%, certified registered nurse anesthetists 58%, attendings 48%). All but 1 respondent recognized the potential for sugammadex interference with oral hormonal contraception. Far fewer accurately identified potential interference with hormonal intrauterine devices (44%) and hormonal contraceptive implants (55%). The manufacturer's recommended 7-day duration of alternative contraception was correctly identified by 72% of respondents; others (22%) reported longer durations (range 10-30 days). Most (78% overall) agreed/strongly agreed that potential interference with contraceptive effectiveness should be discussed with patients preoperatively. Despite the majority (86% overall) that endorsed shared decision-making and inviting patient input regarding choice between sugammadex and neostigmine, many respondents reported "rarely/never" having discussed this drug interaction with patients in actual clinical practice, either preoperatively (67%) or postoperatively (80%). Furthermore, most respondents (79%) reported "rarely/never" administering neostigmine to intentionally avoid this drug interaction. Two years after designating sugammadex as antagonist of choice, physician and nurse anesthesia providers reported seldom inquiring about contraceptive use among women of childbearing potential and rarely discussing potential risk of contraceptive failure from sugammadex exposure. Most lack accurate knowledge of sugammadex interference with hormonal intrauterine and subcutaneous contraceptive devices. Although most endorse preoperative counseling and support patient autonomy or shared decision-making regarding choice of reversal agent, the same respondents report rarely, if ever, actualizing these positions in clinical practice. These conflicting findings highlight the need for education regarding residual neuromuscular block versus adverse drug interactions, collaboration among providers involved in patient counseling, and intentional mindfulness of reproductive justice when caring for women of childbearing potential.