Comparison of the neuromuscular blocking effect of cisatracurium and atracurium on the larynx and the adductor pollicis

Superior Laryngeal Nerve Block for Microlaryngoscopic Surgery: A Systematic Review and Meta-Analysis

OBJECTIVES

To assess the safety and efficacy of superior laryngeal nerve block (SLNB) for microlaryngoscopic surgery (MLS).

DATA SOURCES

PubMed, Embase, Web of Science, Ovid Medline, Cochrane Library, CNKI database, VIP database, Wanfang database, and trial registry databases.

METHODS

PICOS principles were performed: adults undergoing MLS receiving SLNB compared with no-SLNB in randomized controlled trials were included. Primary outcome included the incidence of severe postoperative sore throat (POST). Secondary outcomes included perioperative mean arterial pressure (MAP) and heart rate (HR), incidence of severe postoperative cough, and anesthesia recovery time.

RESULTS

Eleven articles with 728 patients were included. Results indicated that SLNB provides lower incidence of severe POST in post-extubation 30 min (relative ratio [RR] = 0.13; 95% confidence intervals [CIs]: 0.05 ~ 0.34), 2 h (RR = 0.09; 95% CI: 0.02 ~ 0.36), 4-6 h (RR = 0.11; 95% CI: 0.03 ~ 0.41), and 24 h (RR = 0.15; 95% CI: 0.03 ~ 0.83); lower MAP (tracheal intubation: standardized mean difference [SMD] = -1.59; 95% CI: -1.69 to -0.42); suspension laryngoscope insertion: (SMD = -0.98; 95% CI: -1.49 to -0.46); tracheal extubation: (SMD = -0.78; 95% CI:-1.24 to -0.31); post-extubation 5 min: (SMD = -0.95; 95% CI: -1.41 to -0.49); lower HR (tracheal intubation: mean difference [MD] = -9.71; 95% CI: -17.16 to -2.27); suspension laryngoscope insertion: (MD = -8.64; 95% CI: -16.79 to -0.49); tracheal extubation: (MD = -10.13; 95% CI: -17.86 to -2.39); post-extubation 5 min: (MD = -13.44; 95% CI: -22.53 to -4.35); lower incidence of severe postoperative cough in post-extubation 30 min (RR = 0.18; 95% CI: 0.06 ~ 0.57) and 2 h (RR = 0.13; 95% CI: 0.02 ~ 0.69); and shorter anesthesia recovery time (MD = -5.34; 95% CI: -8.81 to -1.86) compared to controls.

CONCLUSIONS

SLNB could provide lower incidence of severe POST, more stable perioperative MAP and HR, lower incidence of severe postoperative cough, and shorter anesthesia recovery time for MLS.

LEVEL OF EVIDENCE

I Laryngoscope, 134:3437-3446, 2024.

Evaluation of the three different doses of cisatracurium during general anaesthesia: A prospective randomized study

Background and Aims

The present study was conducted to determine the optimal dose of cisatracurium for intubating conditions and onset and offset of neuromuscular blockade. Data in Indian population are scarce, and hence, the present study was planned to evaluate different doses of cisatracurium.

Material and Methods

The prospective randomized double-blind study was conducted on 180 patients of either sex in the age group of 20-60 yrs., having physical status class I to III, scheduled for surgery under general anesthesia. After exclusion 154 patients were randomly divided into three groups comprising 52, 51, and 51, respectively, in Group A, Group B, and group C. They received 0.1 mgkg-1, 0.2 mgkg-1, and 0.3 mgkg-1 of cisatracurium, respectively, to facilitate endotracheal intubation. Time of onset, intubating conditions, hemodynamic parameters, signs of histamine release, and recovery time were noted.

Results

Mean time to onset was maximum in group A (4.37 ± 0.48 minutes) and minimum in group C (2.33 ± 0.43 minutes). Intubating conditions were found excellent in 88% patients in group. Change in HR was found to be non-significant at all time periods, but decrease in MAP was found between 2 and 10 minutes in group C. Duration of action was longest in group C.

Conclusion

We conclude that cisatracurium in dose of 0.2 mgkg-1 and 0.3 mgkg-1 provides good-to-excellent intubating conditions within less than 3 minutes.

Deep Neuromuscular Block for Endolaryngeal Surgery: A Systematic Review and Meta-Analysis

OBJECTIVES

To determine the safety and efficacy of deep neuromuscular block (NMB) for endolaryngeal surgery.

DATA SOURCES

PubMed, Web of Science, Cochrane Library, Ovid Medline, Embase, China National Knowledge Infrastructure, Wanfang, VIP databases, and trial registry database.

METHODS

Inclusion criteria followed the PICOS principles: Participants, adults undergoing endolaryngeal surgery; Intervention, deep NMB performed during the surgery; Control, no-deep NMB performed; Outcomes, primary outcome: the incidence of clinically acceptable surgical conditions.

SECONDARY OUTCOME

the incidence of intraoperative complications (including vocal fold movement and coughing) and total incidence of postoperative complications [including postoperative residual curarization (PORC), postoperative sore throat (POST), and postoperative nausea and vomiting (PONV)]. Study design, randomized controlled trials (RCTs). Duplicate publications, editorials, letters, abstracts, and reviews were excluded.

RESULTS

Four articles with 242 patients were identified for analysis. The results indicated that compared with no-deep NMB, deep NMB provides a higher incidence of clinically acceptable surgical conditions (98.36% vs. 76.67%; relative ratio [RR] = 1.29, 95% CI: 1.07-1.56), a lower incidence of intraoperative complications (10.83% versus 37.16%; RR = 0.32; 95% CI: 0.21-0.49) (lower incidence of vocal fold movement [1.85% vs. 34%; RR = 0.08, 95% CI: 0.02-0.41] and coughing [15.53% vs. 38.78%; RR = 0.42, 95% CI: 0.27-0.66]). There were no differences in the overall incidence of postoperative complications (RR = 2.10, 95% CI: 0.12-36.40).

CONCLUSIONS

Based on current published evidence, deep NMB provides better surgical conditions with a higher incidence of clinically acceptable surgical conditions and a lower incidence of intraoperative complications (lower incidence of vocal fold movement and coughing) without increasing the overall incidence of postoperative complications.

LEVEL OF EVIDENCE

1 Laryngoscope, 133:2055-2065, 2023.

Preparing for the unexpected: special considerations and complications after sugammadex administration

Sugammadex, a modified gamma-cyclodextrin, has changed clinical practice of neuromuscular reversal dramatically. With the introduction of this selective relaxant binding agent, rapid and reliable neuromuscular reversal from any depth of block became possible. Sugammadex can reverse neuromuscular blockade without the muscarinic side effects typically associated with the administration of acetylcholinesterase inhibitors. However, what remained unchanged is the incidence of residual neuromuscular blockade. It is known that sugammadex cannot always prevent its occurrence, if appropriate dosing is not chosen based on the level of neuromuscular paralysis prior to administration determined by objective neuromuscular monitoring. Alternatively, excessive doses of sugammadex administered in an attempt to ensure full and sustained reversal may affect the effectiveness of rocuronium in case of immediate reoperation or reintubation. In such emergent scenarios that require onset of rapid and reliable neuromuscular blockade, the summary of product characteristics (package insert) recommends using benzylisoquinolinium neuromuscular blocking agents or a depolarizing agent. However, if rapid intubation is required, succinylcholine has a significant number of side effects, and benzylisoquinolinium agents may not have the rapid onset required. Therefore, prior administration of sugammadex introduces a new set of potential problems that require new solutions. This novel reversal agent thus presents new challenges and anesthesiologists must familiarize themselves with specific issues with its use (e.g., bleeding risk, hypermagnesemia, hypothermia). This review will address sugammadex administration in such special clinical situations.

Recovery from rocuronium-induced neuromuscular block was longer in the larynx than in the pelvic limb of anesthetized dogs

OBJECTIVE

To determine if neuromuscular monitoring at the pelvic limb accurately reflects neuromuscular function in the larynx after administration of rocuronium in anesthetized dogs.

STUDY DESIGN

Prospective experimental study.

ANIMALS

Six healthy Beagle dogs.

METHODS

Anesthesia was maintained in dogs with isoflurane and a continuous infusion of dexmedetomidine. Rocuronium (0.6 mg kg^-1) was administered intravenously to induce neuromuscular block. Train-of-four (TOF) impulses were applied to the left recurrent laryngeal nerve (RLn) and the peroneal nerve (Pn). The evoked TOF ratio (TOFR; T4:T1) was measured with electromyography (EMG) simultaneously at the larynx and at the pelvic limb. Spontaneous recoveries of T1 to 25% (T1_25%) and 75% (T1_75%) of twitch height, and to TOFR of 0.70 and 0.90 (TOFR_0.90) at each EMG site were compared.

RESULTS

Data from five dogs were analyzed. Times to T1_25% were similar at the pelvic limb and larynx when measured by EMG; time to T1_75% was slower at the larynx by 6±4 minutes (p=0.012). The larynx had a slower recovery to TOFR_0.70 (41±13 minutes) and TOFR_0.90 (45±13 minutes) than did the pelvic limb [29±8 minutes (p=0.011) and 33±9 minutes (p=0.003), respectively]. When the pelvic limb EMG returned to TOFR_0.70 and TOFR_0.90, the larynx EMG TOFR_0.70 and TOFR_0.90 values were 0.32±0.12 (p=0.001) and 0.38±0.13 (p=0.001), respectively.

CONCLUSIONS AND CLINICAL RELEVANCE

After administration of rocuronium, neuromuscular function assessed by EMG recovered approximately 36% slower at the larynx than at the pelvic limb. The results in these dogs suggest that quantitative neuromuscular monitoring instrumented at a pelvic limb may be unable to exclude residual block at the larynx in anesthetized dogs.

Comparison of etomidate and propofol on intubating conditions and the onset time associated with cisatracurium administration

Background

This study compared intubating conditions and the onset time associated with administration of cisatracurium, a nondepolarizing neuromuscular blocker with a relatively slow onset, according to prior injection of one of two intravenous anesthetic agents: propofol or etomidate.

Methods

Forty-six female patients, undergoing general anesthesia and endotracheal intubation for elective surgery, were randomized to two groups; group P were administered propofol (2 mg/kg) prior to cisatracurium (0.2 mg/kg); group E were administered etomidate (0.3 mg/kg) prior to cisatracurium (0.2 mg/kg). We measured intubating conditions and the onset time according to the types of intravenous anesthetic administered. Measurements of heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP) were taken immediately prior to induction; immediately and 1 min after IV anesthetic administration; and immediately and 1, 2, 3, 4, 5, 7, and 15 min after endotracheal intubation.

Results

Intubating conditions were superior in group E compared with group P (P = 0.009). The average onset time of cisatracurium was more rapid in group E (155.74 ± 32.92 s vs. 185.26 ± 38.57 s in group P; P = 0.008). There were no group differences in SBP, DBP, and HR following intravenous anesthetic drug injection and endotracheal intubation. However, SBP and DBP were substantially higher in group E after endotracheal intubation.

Conclusions

Etomidate improves intubating conditions and provide a more rapid onset time of cisatracurium during anesthetic induction compared to propofol.

Anesthesiologist's satisfaction using between cisatracurium and rocuronium for the intubation in the anesthesia induced by remifentanil and propofol

BACKGROUND

Although cisatracurium has many advantages in anesthetic practices, the best choice of a nondepolarizing neuromuscular blocking agent that can replace succinylcholine is rocuronium. However, it is reported that remifentanil with propofol might provide reliable intubating condition, even without a neuromuscular blocking agent; therefore, it might improve the intubating condition with cisatracurium. This study examined intubating conditions after administering rocuronium or cisatracurium in a rapid sequence induction with remifentanil-propofol.

METHODS

Fifty two ASA physical status 1 or 2 adult patients scheduled for an elective surgery were enrolled in a randomized double-blinded trial. Anesthesia was induced in all patients with propofol 2.0 mg/kg and remifentanil 0.5 µg/kg, administered over 60 seconds. Rocuronium 0.9 mg/kg (3 × ED(95), R group, n = 23) or cisatracurium 0.15 mg/kg (3 × ED(95), C group, n = 29) was administered after the induction sequence. Laryngoscopy was attempted when the anesthesiologist thought it was 90 seconds after drug administration and appropriate time for intubation. The examiner, another anesthesiologist, recorded the exact time to intubation and suppression of maximal T1 on TOF. The intubating condition was assessed by the first anesthesiologist, as excellent, good, poor or not possible.

RESULTS

The best time to laryngoscopy was predicted by measuring TOF and was found to be significantly longer in the C group (197 ± 53 s) than in the R group (102 ± 49 s) (P value < 0.05). However, time to larygoscopy, intubating condition during the laryngoscopy, and hemodynamic changes after intubation was similar in both groups.

CONCLUSIONS

Despite fundamentally slower onset time, cisatracurium can provide quite good intubating conditions, which were comparable to those achieved with equipotent doses of rocuronium, which is more expensive in anesthesia inducted with remifentanil and propofol.

Effects on Intubating Conditions of Pretreatment with Remifentanil before Administration of Cisatracurium

Cisatracurium provides superior hemodynamic stability with only minor release of histamine, and its metabolism via Hoffman elimination is independent of organ function. However, use of cisatracurium is limited because of reportedly slower onset and unsatisfactory intubating conditions. Many studies have shown that remifentanil might provide reliable intubating conditions; thus, we hypothesized that pretreatment with remifentanil before administration of cisatracurium might result in acceptable intubating conditions. Sixty healthy patients scheduled for elective surgery were enrolled and randomly divided into three groups: saline (Group I, n=20), remifentanil 0.5 µg/kg (Group II, n=20), and remifentanil 1.0 µg/kg (Group III, n=20). The anesthesia was induced with propofol 2.0 µg/kg given intravenously over 30 s followed by injection over 30 s of a different dose of remifentanil according to the study protocol. We examined the intubating condition by jaw relaxation, vocal cord state, and diaphragmatic response 90 s after administering cisatracurium. We also measured mean blood pressure, heart rate, and the onset time, which is the interval from the end of neuromuscular blocking agent administration until suppression of maximal T1 on a train-of four sequence. The mean values of the intubating condition after endotracheal intubation in Groups II and III were significantly lower than that in Group I (p<0.005), although the overall onset time of cisatracurium did not differ significantly between the three groups. Our results suggest that supplementation with remifentanil in an induction regimen with cisatracurium improves the quality of the intubating condition even though the onset time of cisatracurium is not shortened.

Cisatracurium in different doses versus atracurium during general anesthesia for abdominal surgery

Background:

Cisatracurium in clinical practice is devoid of histamine-induced cardiovascular effects. On the other hand, 2 ED₉₅ doses of cisatracurium (100 µ g/kg) do not create satisfactory intubating conditions such as those seen with equipotent doses of atracurium. The recommended intubating dose of cisatracurium is 3 ED₉₅. To understand this discrepancy better, we evaluated the potency and onset of atracurium and cisatracurium.

Materials and Methods:

The study designed as randomized controlled clinical trial to compare between atracurium (2×ED₉₅) and different doses of cisatracurium (2×ED₉₅, 4×ED₉₅, 6×ED₉₅) regarding onset time, duration of action, condition of intubation, hemodynamic effects, and sings of histamine release clinically. Sixty four patients were randomly assigned to one of four groups, the first group (group 1) received 2×ED₉₅ dose of atracurium, group 2 received 2×ED₉₅ dose of cisatracurium, group 3 received 4×ED₉₅ dose of cisatracurium, while group 4 received 6×ED₉₅ dose of cisatracurium. The Datex relaxograph (Type NMT-100-23-01, S/N: 37541) for neuromuscular monitoring was used.

Results:

HR, MABP was statistically significant increased post-intubation with administration of 2×ED₉₅ dose of atracurium in group 1 and the same dose of cisatracurium in group 2 but 5-20 min later was not statistically significant with administration of 4×ED₉₅ and 6×ED₉₅ doses of cisatracurium in groups 3 and 4, respectively. Onset time was found to be significantly lower with 2×ED₉₅ dose of atracurium than with the same dose of cisatracurium. At the same time, higher doses of cisatracurium (4×ED₉₅ and 6×ED₉₅) showed onset time and longer duration of action that was significantly lower than with atracurium and with lower dose of cisatracurium (2×ED₉₅). Only 6×ED₉₅ dose of cisatracurium showed statistically significant difference versus the atracurium dose with higher percentages of patients with excellent condition of intubation. 4×ED₉₅ and 6×ED₉₅ doses of cisatracurium were significantly better than 2×ED₉₅ dose of cisatracurium. 2×ED₉₅ dose of atracurium and 2×ED₉₅ dose of cisatracurium were similar, while 4×ED₉₅ and 6×ED₉₅ doses of cisatracurium were significantly better than atracurium and 2×ED₉₅ dose of cisatracurium.

Conclusion:

The same dose (2×ED₉₅ dose) atracurium is more effective neuromuscular blocking agent than cisatracurium, while higher doses of cisatracurium 4×ED₉₅ and 6×ED₉₅ provide more effective, more rapid neuromuscular blocking with longer duration of action, stable hemodynamic status, and no associated signs of histamine release clinically.

Primingtechnik mit Cisatracurium

OBJECTIVE

Priming can significantly shorten the onset of nondepolarizing neuromuscular blocking agents (NNBA) measured at the adductor pollicis muscle (APM). In spite of the known risks, priming is very popular especially in cases where NNBAs with a long onset time are used. However, there are no data regarding the onset of action for a priming technique measured at the laryngeal muscles although these muscles are of great importance for conditions of intubation and patient safety. The aim of this study was to compare a bolus application and a priming technique with respect to the laryngeal onset time and peak effect.

PATIENT AND METHODS

After approval of the local ethics committee and written informed consent, 36 patients undergoing elective thyroid surgery were enrolled in the study. Anesthesia was induced and maintained with a target controlled infusion of propofol (target concentration 2.7-6.0 microg/ml) and infusion of remifentanil (0.25-0.75 microg/kgbw/min). After loss of consciousness, a tube with a surface electrode was placed into the trachea without the application of any neuromuscular blocking agent. Neuromuscular monitoring consisted of evoked electromyography (EMG) of the laryngeal adductor muscles via the surface electrode and evoked acceleromyography (TOF Guard) of the right adductor pollicis muscle (APM). After transcutaneous stimulation of the recurrent laryngeal nerve and ulnar nerve, either 0.9% NaCl followed by 0.1 mg/kgbw cisatracurium after 3 min (bolus group, n=12), a priming dose of 0.01 mg/kgbw cisatracurium followed by 0.09 mg/kgbw 3 min later (low dose priming group, n=12) or a priming dose of 0.015 mg/kgbw cisatracurium followed by cisatracurium 0.085 mg/kgbw 3 min later (high dose priming group, n=12) were injected. Lag time, onset time and peak effect of NMB were recorded and compared between the groups.

RESULTS

Demographic data, lag time and peak effect were comparable between the three groups. Onset time at the laryngeal muscles was significantly shorter in the high dose priming group (80+/-17 s), when compared to the low dose priming group (128+/-23 s) and bolus group (142+/-29 s). Onset time at the APM was also significantly shorter in the high dose priming group (154+/-35 s), when compared with the bolus group (226+/-76 s). The recovery of the neuromuscular function measured at the APM showed no differences between the groups.

CONCLUSION

Our results show that only high dose priming of cisatracurium can significantly shorten the laryngeal onset time. However, clinical routine use is not recommended due to possible side-effects.

Brief review: Neuromuscular monitoring: an update for the clinician

PURPOSE

To review established techniques and to provide an update on new methods for clinical monitoring of neuromuscular function relevant to anesthesia.

SOURCE

A PubMed search of relevant article for the period 1985-2005 was undertaken, and bibliographies were scanned for additional sources.

PRINCIPAL FINDINGS

There is no substitute for objective neuromuscular monitoring; for research purposes, mechanomyography (MMG) is the gold standard; however, the most versatile method in the clinical setting is acceleromyography since it can be applied at various muscles and has a long track record of clinical utility. Kinemyography is valid to monitor recovery of neuromuscular transmission at the adductor pollicis muscle (AP), whereas phonomyography is easy to apply to various muscles and shows promising agreement with MMG. Monitoring of the corrugator supercilii muscle (CS) may be used to determine the earliest time for tracheal intubation as it reflects laryngeal relaxation better than monitoring at the AP. Recovery of neuromuscular transmission is best monitored at the AP, since it is the last muscle to recover from neuromuscular blockade (NMB). If train-of-four (TOF) stimulation is used, a TOF-ratio > 0.9 should be the target before awakening the patient. If surgery or the type of anesthesia necessitates NMB of a certain degree, e.g., TOF-ratio = 0.25, monitoring of muscles which best reflect the degree of NMB at the surgical site is preferable.

CONCLUSION

Objective methods should be used to monitor neuromuscular function in clinical anesthesia. Acceleromyography offers the best compromise with respect to ease of use, practicality, versatility, precision and applicability at various muscles. The CS is the optimal muscle to determine the earliest time for intubation, e.g., for rapid sequence induction.

Effect of ephedrine on the onset time of succinylcholine

BACKGROUND

The aim of this study was to evaluate the effect of ephedrine administered prior to induction of anaesthesia on the onset time of succinylcholine for endotracheal intubation.

METHODS

Patients were randomly assigned to receive intravenously (i.v.) either 70 microg kg(-1) of ephedrine (Group I; n = 25) or saline (Group II; n = 25) 3 min before induction of anaesthesia. Induction of anaesthesia was provided with propofol 2 mg kg(-1) plus remifentanil 1 microg kg(-1). Onset time and duration of muscle fasciculation and onset time of succinylcholine were recorded. Intubation was attempted after establishment of 100% thumb relaxation and difficulties were recorded. Heart rate, pulse oxymetry (SpO2) and mean arterial pressure (MAP) were also recorded.

RESULTS

The onset time of succinylcholine were significantly (P < 0.001) shorter in Group I (26 +/- 4 s), when compared with Group II (43 +/- 6 s). Patients in Group I were intubated at 49 +/- 7 s compared with 68 +/- 10 s in Group II. The score of intubation was similar in both groups. Duration of muscle fasciculation was longer in Group II. Heart rate and MAP increased significantly (P < 0.05) after ephedrine injection, compared with the baseline value in Group I.

CONCLUSIONS

The onset time of succinylcholine can be shortened with ephedrine pretreatment.