The arousal effect of sugammadex reversal of neuromuscular blockade differs with anesthetic depth in propofol-remifentanil anesthesia: a randomized controlled trial

Sugammadex reverses neuromuscular blockade by encapsulating steroidal neuromuscular blockers; therefore, it does not pharmacologically affect sedation levels. However, some clinicians avoid using it because of sudden unwanted acting out or patient arousal. Previous studies suggested sugammadex-induced awakening, but frontal muscle contraction after sugammadex administration compromised reliability of results obtained from EEG-based anesthesia depth monitoring tools like bispectral index (BIS). We hypothesized that sugammadex would affect patients' arousal depending on their baseline levels of sedation. We evaluated arousal signs after sugammadex administration with BIS between 25 - 35 and 45 - 55 under steady-state propofol-remifentanil anesthesia at the end of a surgery (n = 33 in each group). After sugammadex administration, twelve patients with a BIS of 45 - 55 showed clinical signs of awakening but none with a BIS of 25 - 35 (36.4% vs. 0%, P = 0.001). The distribution of the modified observer's assessment of alertness/sedation scale scores was also significantly different between the two groups (P < 0.001). Changes in the BIS were significantly greater in the BIS 45 - 55 than in the 25 - 35 group (median difference, 7; 95% CI 2 - 19, P = 0.002). Arousal after sugammadex was affected by patient sedation levels, and clinical signs of awakening appeared only in those with BIS 45 - 55. Unwanted arousal of the patient should be considered when using sugammadex under shallow anesthesia.Clinical trial registry number: Clinical Trial Registry of Korea ( https://cris.nih.go.kr ; Principal investigator: Jieae Kim; Registration number: KCT0006248; Date of first registration: 11/06/2021).

Sugammadex Is Associated With Reduced Pulmonary Complications in Patients With Respiratory Dysfunction

INTRODUCTION

Use of sugammadex is associated with fewer postoperative pulmonary complications (PPCs). This study investigated the relationship between sugammadex and PPCs in specific patients with respiratory dysfunction.

MATERIALS AND METHODS

We reviewed the electronic medical and anesthesia records of patients with respiratory dysfunction who underwent laparoscopic gastric or intestinal surgery at a single center between May 1, 2018 and December 31, 2019. The patients were divided into the sugammadex group and the nonsugammadex group, based on whether they received sugammadex or neostigmine. Binary logistic regression analyses were used to characterize the differences in incidence of PPC.

RESULTS

A total of 112 patients were included, of which 46 patients (41.1%) received sugammadex. In the logistic regression analysis, the incidences of PPC were fewer in the sugammadex group. Postoperative fever (odds ratio [OR] 0.330; 95% confidence interval [CI] 0.137-0.793, P = 0.0213), postoperative intensive care unit admission (OR 0.204; 95% CI 0.065-0.644, P = 0.007), cough (OR 0.143; 95% CI 0.061- 0.333, P < 0.001), pleural effusion (all) (OR: 0.280; 95% CI 0.104- 0.759, P = 0.012), pleural effusion (massive) (OR: 0.142; 95% CI 0.031- 0.653, P = 0.012), and difficulty in breathing (OR: 0.111; 95% CI 0.014-0.849, P = 0.039) showed significant differences between the two groups.

CONCLUSIONS

Sugammadex is associated with a reduction in PPC in patients with respiratory dysfunction.

Effect of sugammadex on processed EEG parameters in patients undergoing robot-assisted radical prostatectomy

BACKGROUND

Sugammadex has been associated with increases in the bispectral index (BIS). We evaluated the effects of sugammadex administration on quantitative electroencephalographic (EEG) and electromyographic (EMG) measures.

METHODS

We performed a prospective observational study of adult male patients undergoing robot-assisted radical prostatectomy. All patients received a sevoflurane-based general anaesthetic and a continuous infusion of rocuronium, which was reversed with 2 mg kg-1 of sugammadex i.v. BIS, EEG, and EMG measures were captured with the BIS Vista™ monitor.

RESULTS

Twenty-five patients were included in this study. Compared with baseline, BIS increased at 4-6 min (β coefficient: 3.63; 95% confidence interval [CI]: 2.22-5.04; P<0.001), spectral edge frequency 95 (SEF95) increased at 2-4 min (β coefficient: 0.29; 95% CI: 0.05-0.52; P=0.016) and 4-6 min (β coefficient: 0.71; 95% CI: 0.47-0.94; P<0.001), and EMG increased at 4-6 min (β coefficient: 1.91; 95% CI: 1.00-2.81; P<0.001) after sugammadex administration. Compared with baseline, increased beta power was observed at 2-4 min (β coefficient: 93; 95% CI: 1-185; P=0.046) and 4-6 min (β coefficient: 208; 95% CI: 116-300; P<0.001), and decreased delta power was observed at 4-6 min (β coefficient: -526.72; 95% CI: -778 to -276; P<0.001) after sugammadex administration. Neither SEF95 nor frequency band data analysis adjusted for EMG showed substantial differences. None of the patients showed clinical signs of awakening.

CONCLUSIONS

After neuromuscular block reversal with 2 mg kg-1 sugammadex, BIS, SEF95, EMG, and beta power showed small but statistically significant increases over time, while delta power decreased.

Effect of intraoperative muscle relaxation reversal on the success rate of motor evoked potential recording in patients undergoing spinal surgery: a randomized controlled trial

BACKGROUND

Partial neuromuscular blockade (NMB) has been applied for some surgeries to reduce bleeding and prevent patient movement for spinal surgery. Sugammadex selectively binds to rocuronium in the plasma and consequently lowers the rocuronium concentration at the neuromuscular junction. In this study, we aimed to observe whether the success rate of transcranial motor-evoked potential (TceMEP) can be increased by sugammadex compared with partial NMB during spinal surgery.

METHODS

Patients who underwent elective spinal surgery with TceMEP monitoring were randomly assigned to the sugammadex group and control group. Rocuronium was continuously infused to maintain the train of four counts (TOFc) = 2. The sugammadex group discontinued rocuronium infusion at the time of TceMEP monitoring and was infused with 2 mg/kg sugammadex; the control group was infused with the same dose of saline.

RESULTS

A total of 171 patients were included. The success rate of TceMEP monitoring in the sugammadex group was significantly higher than that in the control group. TceMEP amplitudes were greater in the sugammadex group than in the control group at 5 min, 10 min, and 20 min after the start of motor-evoked potential monitoring. The latencies of upper extremity TceMEPs monitoring showed no difference between groups. TOF ratios were greater in the sugammadex group at 5 min, 10 min, and 20 min after the start of motor-evoked potential monitoring. There were no adverse effects caused by sugammadex.

CONCLUSIONS

Sugammadex can improve the success rate of motor-evoked potential monitoring compared with moderate neuromuscular blockade induced by continuous infusion of rocuronium in spinal surgery.

TRIAL REGISTRATION

The study was registered on clinicaltrials.gov.cn on 29/10/2020 (trial registration number: NCT04608682).

Association of sugammadex reversal of neuromuscular block and postoperative length of stay in the ambulatory care facility: a multicentre hospital registry study

BACKGROUND

Encapsulation of rocuronium or vecuronium with sugammadex can reverse neuromuscular block faster than neostigmine reversal. This pharmacodynamic profile might facilitate patient discharge after ambulatory surgery.

METHODS

We included patients who underwent ambulatory surgery with general anaesthesia and neuromuscular block between 2016 and 2021 from hospital registries at two large academic healthcare networks in the USA. The primary outcome was postoperative length of stay in the ambulatory care facility (PLOS-ACF). We examined post hoc whether the type of reversal affects postoperative nausea and vomiting and direct hospital costs.

RESULTS

Among the 29 316 patients included, 8945 (30.5%) received sugammadex and 20 371 (69.5%) received neostigmine for reversal. PLOS-ACF and costs were lower in patients who received sugammadex vs neostigmine (adjusted difference in PLOS-ACF: -9.5 min; 95% confidence interval [95% CI], -10.5 to -8.5 min; adjusted difference in direct hospital costs: -US$77; 95% CI, -$88 to -$66; respectively; P<0.001). The association was magnified in patients over age 65 yr, with ASA physical status >2 undergoing short procedures (<2 h) (adjusted difference in PLOS-ACF: -18.2 min; 95% CI, -23.8 to -12.4 min; adjusted difference in direct hospital costs: -$176; 95% CI, -$220 to -$128; P<0.001). Sugammadex use was associated with reduced postoperative nausea and vomiting (17.2% vs 19.6%, P<0.001), which mediated its effects on length of stay.

CONCLUSIONS

Reversal with sugammadex compared with neostigmine was associated with a small decrease in postoperative length of stay in the ambulatory care unit. The effect was magnified in older and high-risk patients, and can be explained by reduced postoperative nausea and vomiting. Sugammadex reversal in ambulatory surgery may also help reduce cost of care.

Sugammadex versus neostigmine for neuromuscular blockade reversal in outpatient surgeries: A randomized controlled trial to evaluate efficacy and associated healthcare cost in an academic center

Introduction

Neuromuscular blockade is an essential component of the general anesthesia as it allows for a better airway management and optimal surgical conditions. Despite significant reductions in extubation and OR readiness-for-discharge times have been associated with the use of sugammadex, the cost-effectiveness of this drug remains controversial. We aimed to compare the time to reach a train-of-four (TOF) response of ≥0.9 and operating room readiness for discharge in patients who received sugammadex for moderate neuromuscular blockade reversal when compared to neostigmine during outpatient surgeries under general anesthesia. Potential reduction in time for OR discharge readiness as a result of sugammadex use may compensate for the existing cost-gap between sugammadex and neostigmine.

Methods

We conducted a single-center, randomized, double arm, open-label, prospective clinical trial involving adult patients undergoing outpatient surgeries under general anesthesia. Eligible subjects were randomized (1:1 ratio) into two groups to receive either sugammadex (Groups S), or neostigmine/glycopyrrolate (Group N) at the time of neuromuscular blockade reversal. The primary outcome was the time to reverse moderate rocuronium-induced neuromuscular blockade (TOF ratio ≥0.9) in both groups. In addition, post-anesthesia care unit (PACU)/hospital length of stay (LOS) and perioperative costs were compared among groups as secondary outcomes.

Results

Thirty-seven subjects were included in our statistical analysis (Group S= 18 subjects and Group N= 19 subjects). The median time to reach a TOF ratio ≥0.9 was significantly reduced in Group S when compared to Group N (180 versus 540 seconds; p = 0.0052). PACU and hospital LOS were comparable among groups. Postoperative nausea and vomiting was the main adverse effect reported in Group S (22.2% versus 5.3% in Group N; p = 0.18), while urinary retention (10.5%) and shortness of breath (5.3%) were only experienced by some patients in Group N. Moreover, no statistical differences were found between groups regarding OR/anesthesia, PACU, and total admission costs.

Discussion

Sugammadex use was associated with a significantly faster moderate neuromuscular blockade reversal. We found no evidence of increased perioperative costs associated with the use of sugammadex in patients undergoing outpatient surgeries in our academic institution.

Clinical trial registration

[https://clinicaltrials.gov/] identifier number [NCT03579589].

Appropriate dosing of sugammadex for reversal of rocuronium-/vecuronium-induced muscle relaxation in morbidly obese patients: a meta-analysis of randomized controlled trials

Objective

To conduct a meta-analysis to compare different dosing scalars of sugammadex in a morbidly obese population for reversal of neuromuscular blockade (NMB).

Methods

PubMed®, ClinicalTrials.gov, Cochrane Central Register of Controlled Trials (CENTRAL) and Google Scholar were searched for relevant randomized controlled trials (RCTs) comparing lower-dose sugammadex using ideal body weight (IBW) or corrected body weight (CBW) as dosing scalars with standard-dose sugammadex based on total body weight (TBW) among morbidly obese people after NMB. Mean difference with SD was used to estimate the results.

Results

The analysis included five RCT with a total of 444 morbidly obese patients. The reversal time was significantly longer in patients receiving sugammadex with dosing scalar based on IBW than in patients receiving sugammadex with dosing scalar based on TBW (mean difference 55.77 s, 95% confidence interval [CI] 32.01, 79.53 s), but it was not significantly different between patients receiving sugammadex with dosing scalars based on CBW versus TBW (mean difference 2.28 s, 95% CI –10.34, 14.89 s).

Conclusion

Compared with standard-dose sugammadex based on TBW, lower-dose sugammadex based on IBW had 56 s longer reversal time whereas lower-dose sugammadex based on CBW had a comparable reversal time.

Potential Neuroprotective Role of Sugammadex: A Clinical Study on Cognitive Function Assessment in an Enhanced Recovery After Cardiac Surgery Approach and an Experimental Study

Background

Postoperative cognitive dysfunction affects the quality of recovery, particularly affecting the elderly, and poses a burden on the health system. We hypothesize that the use of sugammadex (SG) could optimize the quality of postoperative cognitive function and overall recovery through a neuroprotective effect.

Methods

A pilot observational study on patients undergoing cardiac surgery with enhanced recovery after cardiac surgery (ERACS) approach, was designed to compare SG-treated (n = 14) vs. neostigmine (NG)-treated (n = 7) patients. The Postoperative Quality Recovery Scale (PQRS) was used at different times to evaluate cognitive function and overall recovery of the patients. An online survey among anesthesiologists on SG use was also performed. Additionally, an animal model study was designed to explore the effects of SG on the hippocampus.

Results

Sugammadex (SG) was associated with favorable postoperative recovery in cognitive domains particularly 30 days after surgery in patients undergoing aortic valve replacement by cardiopulmonary bypass and the ERACS approach; however, it failed to demonstrate a short-term decrease in length of intensive care unit (ICU) and hospital stay. The survey information indicated a positive appreciation of SG recovery properties. SG reverts postoperative memory deficit and induces the expression of anti-inflammatory microglial markers.

Conclusion

The results show a postoperative cognitive improvement by SG treatment in patients undergoing aortic valve replacement procedure by the ERACS approach. Additionally, experimental data from an animal model of mild surgery confirm the cognitive effect of SG and suggest a potential effect over glia cells as an underlying mechanism.

Rapid arousal from anaesthesia after reversal of deep rocuronium-induced neuromuscular block with sugammadex in a neuroradiological procedure

We describe the case of a 42-year-old man undergoing elective embolisation of an arteriovenous malformation at the level of the right posterior cerebral artery under propofol anaesthesia. We used the SedLine Brain Function Monitor (Masimo) to titrate the anaesthetic depth with propofol. At the end of the procedure, the patient aroused from anaesthesia very rapidly after the reversal of deep neuromuscular block with sugammadex, despite still significant calculated doses of propofol at the effect site. This rapid arousal was monitored using the SedLine Brain Function Monitor.

Effect of reversal of residual neuromuscular blockade on the amplitude of motor evoked potentials: a randomized controlled crossover study comparing sugammadex and placebo

PURPOSE

To compare the amplitude changes in motor evoked potentials (MEP) with reversal of residual neuromuscular blockade using sugammadex or placebo in patients with cervical myelopathy.

METHODS

In this prospective randomized double-blind, placebo-controlled crossover trial, 38 patients with cervical myelopathy undergoing posterior cervical decompression and fusion were randomized to either sugammadex (2mg/kg) or placebo. The primary outcome measure was the increase in amplitude of the MEP in the first dorsal interossei (FDI) muscle at 3 min. Mann-Whitney U test was used to analyze the primary outcome measure.

RESULTS

There was a significant increase in the amplitude of MEP at 3 min with sugammadex when compared to placebo group. The median (IQR) increase in MEP amplitude (μV) at 3 min from the left FDI in sugammadex and placebo group was 652.9 (142:1650) and 20.6 (-183.5:297.5) (p <0.001), respectively. Corresponding values from right FDI were 2153.4 (1400:4536.8) and 55(-65.2:480.8) (p=<0.001).

CONCLUSION

Our study showed that there was a 200% increase in the MEP amplitude in the first dorsal interosseous muscle at 3 min following reversal of residual neuromuscular blockade with sugammadex. By ensuring that maximal MEP amplitude is recorded at baseline, early commencement of neuromonitoring can be achieved.

TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION

The study was registered at http://clinicaltrials.gov , ID NCT03087513, Feb 5^th 2018.

Impact of Sugammadex Versus Neostigmine/Glycopyrrolate on Perioperative Efficiency

Purpose

Neuromuscular blockade in the operating room necessitates the utilization of reversal agents to accelerate postoperative recovery and sustain operating room patient throughput. Cholinesterase inhibitors represent the historical standard of care for neuromuscular blockade reversal within anesthesia practice. Sugammadex, a synthetic gamma-cyclodextrin, was introduced to the market with evidence of more rapid and predictable reversal of neuromuscular blockade compared to alternative agents. Higher medication acquisition costs have limited more extensive use of sugammadex compared to that of neostigmine/glycopyrrolate. The purpose of this study was to examine the impact of sugammadex versus neostigmine/glycopyrrolate on perioperative efficiency to validate medication acquisition cost value.

Methods

A retrospective investigation was performed of patients with a surgical procedure at Houston Methodist Hospital from July 31, 2017 through August 1, 2018. The primary endpoint was time from reversal medication administration to operating room exit. Patient-specific doses were assessed to calculate average medication acquisition costs. The economic benefits of sugammadex were measured through review of average operating room and postanesthesia care unit costs per minute.

Results

There were a total of 640 surgical cases at Houston Methodist Hospital eligible for inclusion into the research study. The time from medication administration to operating room exit was significantly faster for sugammadex compared to neostigmine/glycopyrrolate (P<0.001) upon univariate analysis. However, when measured with linear regression, the difference in operating room exit time between sugammadex and neostigmine/glycopyrrolate was no longer statistically significant (P=0.122). Medication acquisition cost review highlighted a difference of $178.20, favoring use of neostigmine/glycopyrrolate.

Conclusion

The utilization of sugammadex does not correlate to consequential time saved in the operating room or extrapolation to workflow capacity for increased surgical case volume. Consideration of the medication acquisition cost promotes more restrictive use of sugammadex to indications with clinical relevance.

Recovery from Anesthesia after Robotic-Assisted Radical Cystectomy: Two Different Reversals of Neuromuscular Blockade

During robot-assisted radical cystectomy (RARC), specific surgical conditions (a steep Trendelenburg position, prolonged pneumoperitoneum, effective myoresolution until the final stages of surgery) can seriously impair the outcomes. The aim of the study was to evaluate the incidence of postoperative nausea and vomiting (PONV) and ileus and the quality of cognitive function at the awakening in two groups of patients undergoing different reversals. In this randomized trial, patients that were American Society of Anesthesiologists physical status (ASA) ≤III candidates for RARC for bladder cancer were randomized into two groups: In the sugammadex (S) group, patients received 2 mg/kg of sugammadex as reversal of neuromuscolar blockade; in the neostigmine (N) group, antagonization was obtained with neostigmine 0.04 mg/kg + atropine 0.02 mg/kg. PONV was evaluated at 30 min, 6 and 24 h after anesthesia. Postoperative cognitive functions and time to resumption of intestinal transit were also investigated. A total of 109 patients were analyzed (54 in the S group and 55 in the N group). The incidence of early PONV was lower in the S group but not statistically significant (S group 25.9% vs. N group 29%; p = 0.711). The Mini-Mental State test mean value was higher in the S group vs. the N group (1 h after surgery: 29.3 (29; 30) vs. 27.6 (27; 30), p = 0.007; 4 h after surgery: 29.5 (30; 30) vs. 28.4 (28; 30), p = 0.05). We did not observe a significant decrease of the PONV after sugammadex administration versus neostigmine use. The Mini-Mental State test mean value was greater in the S group.

Recovery characteristics of patients receiving either sugammadex or neostigmine and glycopyrrolate for reversal of neuromuscular block: a randomised controlled trial

Sugammadex more rapidly and reliably reverses rocuronium-induced neuromuscular block compared with neostigmine, but it is not known if subsequent patient outcomes, including nausea, vomiting and other aspects of recovery are modified. In this study, we compared the recovery characteristics of sugammadex and neostigmine/glycopyrrolate following reversal of neuromuscular block. This was a single-centre, randomised, blinded, parallel-group clinical trial in women undergoing elective day-surgical laparoscopic gynaecological surgery, with a standardised general anaesthesia regimen that included rocuronium. Neuromuscular block was reversed with either sugammadex 2 mg.kg^-1 or neostigmine 40 μg.kg^-1 and glycopyrrolate 400 μg. The primary outcome was the incidence of nausea and vomiting during the first six postoperative hours. Secondary outcomes included other measures of postoperative recovery such as patient symptoms and recovery scores. Three-hundred and four women were analysed by intention-to-treat (sugammadex n = 151, neostigmine n = 153), which included four major protocol violations. There was no significant difference between sugammadex and neostigmine groups in the incidence of early nausea and vomiting (49.0% vs. 51.0%, respectively; OR 0.92, 95%CI 0.59-1.45; p = 0.731). Double vision (11.5% vs. 20.0%; p = 0.044) and dry mouth (71.6% vs. 85.5%; p = 0.003) were less common after sugammadex. Sedation scores at 2 h were also lower after sugammadex (median (IQR [range]) 0 (0-3 [0-10]) vs. 2 (0-4.[0-10]); p = 0.021). Twenty-four-hour recovery scores were not significantly different between groups. Reversal with sugammadex in this patient population did not reduce postoperative nausea or vomiting compared with neostigmine/glycopyrrolate.

Operating room discharge after deep neuromuscular block reversed with sugammadex compared with shallow block reversed with neostigmine: a randomized controlled trial

OBJECTIVE

To determine if reversing a deep or moderate block with sugammadex, compared with a shallow block reversed with neostigmine, reduces the time to operating room discharge after surgery and the time spent in the postanesthesia care unit.

DESIGN

A randomized controlled trial.

SETTING

Monocentric study performed from February 2011 until May 2012.

PATIENTS

One hundred consenting women with American Society of Anesthesiologists grade I or II were randomized into 2 groups.

INTERVENTION

Laparoscopic hysterectomy was performed under desflurane general anesthesia. For the neostigmine (N) group, 0.45 mg · kg^-1 rocuronium was followed by spontaneous recovery. A 5-mg rescue bolus was administered only if surgical evaluation was unacceptable. At the end of surgery, 50 μg · kg^-1 neostigmine with glycopyrrolate was administered. For the sugammadex (S) group, a higher intubating rocuronium dose (0.6 mg · kg^-1) was followed by 5-mg boluses each time the train-of-four count exceeded 2. Sugammadex (2-4 mg · kg^-1) was administered to reverse the block. All patients were extubated after obtaining a train-of-four ratio of 0.9.

MEASUREMENTS

The duration between the end of surgery and operating room discharge and the time spent in the postanesthesia care unit.

MAIN RESULTS

The time till operating room discharge was shorter and more predictable in group S (9.15±4.28 minutes vs 13.87±11.43 minutes in group N; P=.005). The maximal duration in group S was 22 minutes, compared with 72 minutes in group N. The time spent in the postanesthesia care unit was not significantly different (group S: 47.75±31.77 minutes and group N: 53.43±40.57 minutes; P=.543).

CONCLUSION

Maintaining a deep neuromuscular block during laparoscopic hysterectomy reversed at the end of the procedure with sugammadex enabled a faster and more predictable time till operating room discharge than did the classical combination of a shallower block reversed with neostigmine.

Neostigmine vs. sugammadex: observational cohort study comparing the quality of recovery using the Postoperative Quality Recovery Scale

BACKGROUND

Quality of postoperative recovery is an important outcome after surgery. An observational cohort study was designed to assess the quality of postoperative recovery using the Portuguese version of the Postoperative Quality Recovery Scale (PQRS) in patients treated with neostigmine vs. sugammadex as neuromuscular blocking reversal agents.

METHODS

A convenience sample of 101 adult patients undergoing elective surgery with general anaesthesia and treated with neostigmine (n=48) or sugammadex (n=53) as neuromuscular blocking reversal agents was included. Patients were evaluated using the Portuguese PQRS version at baseline and postoperatively at 15 (T15) and 40 (T40) min and also at days 1 and 3. Recovery was defined as return to baseline values (or better) at each time points.

RESULTS

The PQRS overall recovery rates were similar in both groups, but recoveries in the nociceptive (96.2% vs. 81.3%, P=0.02) and physiological (96.2% vs. 70.2%, P=0.001) domains at T40 were higher in the sugammadex group than in the neostigmine group. Also, there was a trend that patients treated with sugammadex reported significantly better global perspective on the impact of surgery on working capacity and daily activities, as well as higher satisfaction with anaesthetic care.

CONCLUSIONS

This pilot study suggests that sugammadex may improve physiological and nociceptive postoperative recovery as well as patient satisfaction with anaesthetic care. Although we lack an explanation for a possible favourable impact of sugammadex on quality of recovery, our results may provide sufficient preliminary data to justify a randomised trial to explore this possibility.

Elevated BIS and Entropy values after sugammadex or neostigmine: an electroencephalographic or electromyographic phenomenon?

BACKGROUND

Sugammadex is designed to antagonize neuromuscular blockade (NMB) induced by rocuronium or vecuronium. In clinical practice, we have noticed a rise in the numerical values of bispectral index (BIS) and Entropy, two electroencephalogram (EEG) - based depth of anesthesia monitors, during the reversal of the NMB with sugammadex. The aim of this prospective, randomized, double-blind study was to test this impression and to compare the effects of sugammadex and neostigmine on the BIS and Entropy values during the reversal of the NMB.

METHODS

Thirty patients undergoing gynecological operations were studied. Patients were anesthetized with target-controlled infusions of propofol and remifentanil, and rocuronium was used to induce NMB. After operation, during light propofol-remifentanil anesthesia, NMB was antagonized with sugammadex or neostigmine. During the following 5 min, the numerical values of BIS, BIS electromyographic (BIS EMG) and Entropy were recorded on a laptop computer, as well as the biosignal recorded by the Entropy strip. The Entropy biosignal was studied off-line both in time and frequency domain to see if NMB reversal causes changes in EEG.

RESULTS

In some patients, administration of sugammadex or neostigmine caused a significant rise in the numerical values of BIS, BIS EMG and Entropy. This phenomenon was most likely caused by increased electromyographic (EMG) activity. The administration of sugammadex or neostigmine appeared to have only minimal effect on EEG.

CONCLUSION

The EMG contamination of EEG causes BIS and Entropy values to rise during reversal of rocuronium-induced NMB in light propofol-remifentanil anesthesia.