Desflurane reduces the effective therapeutic infusion rate (ETI) of cisatracurium more than isoflurane, sevoflurane, or propofol

Comparison of the synergistic effects of sevoflurane and desflurane on muscle relaxant vecuronium in laparoscopic colon cancer surgery

Sevoflurane and desflurane are commonly used inhalation anesthetics in clinical practice. This study compared the synergistic effects of sevoflurane and desflurane on the muscarinic agent vecuronium in laparoscopic colon cancer surgery. The aim of this study was to compare sevoflurane and desflurane in a synergistic effect on the muscle relaxant vecuronium in laparoscopic colon cancer surgery. Sixty patients undergoing elective laparoscopic radical resection of colon cancer were randomly divided into sevoflurane (n = 30) and desflurane (n = 30) groups. After anesthesia and successful tracheal intubation, patients in both groups were maintained with combined remifentanil. Muscle relaxant effects were monitored in both groups using a muscle relaxant monitor (train of stimuli-Watch), the onset time, T1 and T2 recovery time, and muscle relaxant dosage of vecuronium were observed. Hemodynamic changes were observed in both groups, and the dosage of vasoactive drugs was recorded. The quality of recovery of the patients was evaluated using the Mini-Mental State Examination (MMSE) and the discharge from the Aldrete score criteria. There was no significant difference in the onset time of vecuronium between the two groups (P > .05). The desflurane group's T1 and T2 recovery times were later than that of the sevoflurane group. The dosage of vecuronium was statistically significantly less than that in the sevoflurane group (P < .05); the extubation time in the desflurane group was statistically significantly longer than that in the sevoflurane group (P < .05). There were no significant differences in preoperative and intraoperative mean arterial pressure, heart rate, ephedrine and atropine dosage, MMSE score, and Aldrete score between the 2 groups (P > .05). Compared with sevoflurane, desflurane has a stronger synergistic effect on the muscle relaxant of vecuronium without increasing the incidence of cardiovascular adverse reactions and affecting patient recovery.

Shortening of the twitch stabilization period by tetanic stimulation in acceleromyography in infants, children and young adults (STSTS-Study): a prospective randomised, controlled trial

Acceleromyography is characterised by an increase of the twitch response T1 (first twitch of the train-of-four [TOF]) during first 30 min of monitoring known as the staircase phenomenon. In adults the staircase phenomenon can be avoided by tetanic prestimulation. This study examined, if tetanic prestimulation eliminates the staircase phenomenon in children. After written informed consent, the neuromuscular function of 80 children, 10 in each age group (< 6 months, 6-12 months, 12-24 months, 2-3 years, 3-6 years, 6-12 years, 12-18 years, and ≥ 18 years) was measured on both arms simultaneously over 30 min under general anaesthesia. The ulnaris nerve was stimulated using the TOF technique every 15 s. The twitch response (T1, TOF ratio [TOFR]) was measured by acceleromyography. Before calibration, tetanic prestimmulation (50 Hz for 5 s) was administered to one randomly selected arm. The effect of tetanic prestimulation and age was analysed using general linear models based on the normalized T1 and TOFRs of both arms. Tetanic prestimulation significantly affected T1 values avoiding the staircase phenomenon (p < 0.0001). After 5.8 min [1.0-17.2 min] the normalized T1 values increased to 117% [102-147%] without prestimulation (p < 0.0001) independent of the age group (p = 0.539). The normalized TOFR was stable throughout the observation period of 30 min 100% [95-107%]. Infants (> 12 weeks), children, and young adults (< 18 years) develop similar characteristics of the staircase phenomenon than adults. Tetanic prestimulation prevents the staircase phenomenon in these age groups. The stability of the TOFR reading confirms its value to monitor neuromuscular function over time.Registration: The study was registered as NCT02552875 on Clinical Trials.gov on July 29, 2014.

Comparative study on the pharmacodynamics of cisatracurium: continuous infusion or intermittent bolus injection

OBJECTIVE

To explore a better administration way through comparison of the pharmacodynamics of cisatracurium administered by continuous infusion or intermittent bolus injection.

METHODS

Thirty patients (ASAI-II) who had no neuromuscular disease and underwent selective surgery under general anesthesia were randomly divided into group I and II (each group with 15 patients). In group I, patients received cisatracurium by continuous infusion and in group II, by intermittent bolus injection. The responses of adductor pollicis to train-of-four (TOF) stimulation were monitored. The duration of neuromuscular blockade, recovery index and total dose of cisatracurium consumption were recorded in the two groups. Intravenous anesthesia was used for anesthesia induction and sevoflurane inhalation for maintenance of anesthesia.

RESULTS

The mean infusion rate was significantly lower in group I (0.78 ± 0.15 μg.kg(-1).min(-1)) than in group II (1.09 ± 0.33 μg.kg(-1).min(-1)) (P<0.05). There was no significant difference in duration of neuromuscular blockade between the two groups (P>0.05). The recovery index was 13.13 ± 3.36 min in group I and 14.38 ± 4.48 min in group II, which indicated that the recovery was faster in group I than in group II, but without statistical significance (P>0.05). During the duration of neuromuscular blockade, 8 patients had T(1)<3%, 4 T(1) of 3%-7% and 3 T(1) of 7%-10% in group I; T(1) was maintained between 0 and 20% in group II.

CONCLUSIONS

Although cisatracurium consumption was significantly lower in continuous infusion than in intermittent bolus injection, continuous infusion can obtain more stable neuromuscular blockade than intermittent bolus injection.

Effect of nitrous oxide on cisatracurium infusion demands: a randomized controlled trial

BACKGROUND

Recent studies have questioned our previous understanding on the effect of nitrous oxide on muscle relaxants, since nitrous oxide has been shown to potentiate the action of bolus doses of mivacurium, rocuronium and vecuronium. This study was aimed to investigate the possible effect of nitrous oxide on the infusion requirements of cisatracurium.

METHODS

70 ASA physical status I-III patients aged 18-75 years were enrolled in this randomized trial. The patients were undergoing elective surgery requiring general anesthesia with a duration of at least 90 minutes. Patients were randomized to receive propofol and remifentanil by target controlled infusion in combination with either a mixture of oxygen and nitrous oxide (Nitrous oxide/TIVA group) or oxygen in air (Air/TIVA group). A 0.1 mg/kg initial bolus of cisatracurium was administered before tracheal intubation, followed by a closed-loop computer controlled infusion of cisatracurium to produce and maintain a 90% neuromuscular block. Cumulative dose requirements of cisatracurium during the 90-min study period after bolus administration were measured and the asymptotic steady state rate of infusion to produce a constant 90% block was determined by applying nonlinear curve fitting to the data on the cumulative dose requirement during the study period.

RESULTS

Controller performance, i.e. the ability of the controller to maintain neuromuscular block constant at the setpoint and patient characteristics were similar in both groups. The administration of nitrous oxide did not affect cisatracurium infusion requirements. The mean steady-state rates of infusion were 0.072 +/- 0.018 and 0.066 +/- 0.017 mg * kg-1 * h-1 in Air/TIVA and Nitrous oxide/TIVA groups, respectively.

CONCLUSIONS

Nitrous oxide does not affect the infusion requirements of cisatracurium.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01152905; European Clinical Trials Database at http://eudract.emea.eu.int/2006-006037-41.

Acute desflurane or sevoflurane exposure on a previously stabilized atracurium-induced neuromuscular block

BACKGROUND AND OBJECTIVE

The aim of this prospective study was to compare the effect of the administration of desflurane or sevoflurane to a fixed neuromuscular block.

METHODS

After written consent, 12 patients were anaesthetized with propofol and sufentanil. Atracurium was administered via a continuous infusion in order to obtain 85% twitch depression of the control value assessed by repeated accelerometric stimulation at the adductor pollicis. Once stabilized over the course of 30 min, propofol was discontinued and either desflurane (n = 6) or sevoflurane (n = 6) was delivered at 1 MAC in a mixture of 50% O(2) in air. Study parameters were the magnitude and the time of twitch height variations. Results are presented in mean +/- SD.

RESULT

Exposure to halogenated agents led to a significant reduction in twitch height with similar magnitude between the two agents. However, interaction with desflurane showed an initial and transient rise (35 +/- 22%) in twitch height before subsequent depression occurred. The time to reach 50% of the signal depression in the desflurane group was significantly delayed (25 +/- 7 vs. 11 +/- 4 min in the sevoflurane group; P < 0.01).

CONCLUSIONS

On a stable neuromuscular block elicited by continuous infusion of atracurium, the abrupt administration of desflurane or sevoflurane reduces the accelerometric responses of the adductor pollicis in a similar way. This potentiating effect is produced faster after sevoflurane than after desflurane. With desflurane, a biphasic effect (of a transient and moderate increase followed by depression of the signal) was recorded.

The comparative effect of single dose mivacurium during sevoflurane or propofol anesthesia in children

BACKGROUND

We aimed to randomly compare intubating conditions, recovery characteristics and neuromuscular effects of single dose of mivacurium (0.2 mg.kg(-1)) during sevoflurane vs. propofol anesthesia in 60 healthy children, undergoing inguinal surgery.

METHODS

All children were randomly allocated to receive 2 mg.kg(-1) propofol iv or sevoflurane 8% inspired concentration for induction of anesthesia. Anaesthesia was maintained with 66% nitrous oxide in oxygen and 100-120 microg.kg(-1) propofol or sevoflurane approximately 2-3% inspired concentration with controlled ventilation. The ulnar nerve was stimulated at the wrist by a train-of four (TOF) stimulus every 20 s and neuromuscular function was measured at the adductor pollicis. When the response to TOF was stable, 0.2 mg.kg(-1) mivacurium was given. The trachea was intubated successfully at the first attempt in all patients.

RESULTS

Onset time following a single dose of mivacurium was shorter in the sevoflurane group (2.99 min), than in the propofol group (4.42 min). The times to 25, 50, 75, and 90% recovery were significantly longer in the sevoflurane group (13.1, 15.7, 18.6, and 21.2 min, respectively) than in the propofol group (11.4, 13.2, 14.4, and 17.2 min respectively). TOF ratios of 50, 70, and 90% were significantly occurred later in sevoflurane group than propofol group.

CONCLUSIONS

Our results indicate that when compared with propofol group, the sevoflurane group had an accelerated onset and a delayed recovery of neuromuscular block induced by mivacurium in children.

The staircase phenomenon at the corrugator supercilii muscle in comparison with the hand muscles

BACKGROUND

Phonomyography (PMG) is a novel method to monitor neuromuscular block. It is non-invasive and can be applied to any muscle. It can be used interchangeably with mechanomyography (MMG). The staircase phenomenon has not been investigated for this method or at the corrugator supercilii muscle. The purpose of this work was to determine the staircase effect at three different muscles using two different methods.

METHODS

In 10 patients undergoing general anaesthesia with sevoflurane, using a laryngeal mask airway without the aid of neuromuscular block, one piezo-electric microphone each was applied to the corrugator supercilii muscle and the first dorsal interosseus muscle. In addition, a force transducer was attached to the tip of the thumb to determine the force of the adductor pollicis muscle. Supramaximal stimulation at 1 Hz was used at the ulnar and the facial nerve. All signals were simultaneously recorded for 30 min. Data are presented as means (SD).

RESULTS

The staircase effect was significantly positive for the first dorsal interosseus muscle and the adductor pollicis muscle. The signal potentiation was not significantly different between the first dorsal interosseus muscle with a maximum increase at 148 (19)% using PMG, and the adductor pollicis muscle at 154 (22)% using MMG. The evoked signals reached a plateau after 15-18 min at both muscles. There was only a small initial increase in signal height at the corrugator supercilii to a maximum of 117 (20)% at 7 min, after which the signals decreased to reach a plateau at 25 min. In comparison with the signal height of 105 (25)% at 30 min, there was no significant difference of signal heights throughout the observation period.

CONCLUSIONS

A positive staircase phenomenon is found equally at the first dorsal interosseus muscle and the adductor pollicis muscle. There is no significant staircase effect at the corrugator supercilii muscle.

Artificial blood

Blood substitutes are under development for transfusion in place of donor blood during emergencies and lengthy surgeries. The first generation of blood substitutes is currently in clinical trials.