COMPARISON OF INTUBATING CONDITIONS BETWEEN ATRACURIUM PRIMING, MAGNESIUM SULPHATE PRE-TREATMENT AND COMBINATION OF TWO METHODS ON ONSET AND DURATION OF NEUROMUSCULAR BLOCKADE: A RANDOMIZED DOUBLE BLIND CONTROLLED STUDY

Introduction: Magnesium inhibits acetylcholine release from the presynaptic membrane at the motor end plate; and thus it enhances the effect of non-depolarising muscle relaxants. Priming technique shortens the time of onset of non depolarising neuromuscular relaxants. Thus, the combination of magnesium pre-treatment and priming may be an effective method for achieving an early tracheal intubating condition. We studied the effect of magnesium sulphate pretreatment in combination with atracurium priming on onset and duration of neuromuscular blockade, compared with these methods when used alone. Materials and Methods: 100 patients scheduled for elective surgical procedures under general anaesthesia were divided into 4 groups. Group A (n=25) recieved priming with 0.05 mg/kg atracurium, three minutes before the intubating dose of atracurium 0.5 mg/kg, group M (n=25) was given 50 mg/kg magnesium sulphate as infusion over 10 mins before intubating dose of atracurium, group MA (n=25) received both the magnesium sulphate pretreatment and the priming dose of atracurium. Group N (n = 25) were given 0.5mg/kg atracurium alone as part of general anaesthesia. Tracheal intubation was done when the TOF stimulation showed single twitch which was measured at intervals of every 30 seconds. Parameters studied were the time to onset of neuromuscular blockade and the duration of neuromuscular blockade. Results: The MA group had the shortest onset time (mean±SD) 114.30±20.19 sec (p < 0.001) compared to the other groups. The duration of blockade was prolonged in both Group MA and Group M compared to other groups (P<0.001). Few adverse effects were reported in groups receiving magnesium, but were clinically not significant. Conclusion: Magnesium sulphate pretreatment in combination with atracurium priming shortens the time of onset of neuromuscular blockade when compared to magnesium sulphate pretreatment or priming used alone. Keywords: Atracurium priming, magnesium sulphate, neuromuscular blockade

Use of sugammadex in patients with neuromuscular disorders: a systematic review of case reports

Background Sugammadex is a modified gamma-cyclodextrin that acts by selectively encapsulating free amino-steroidal neuromuscular relaxants. Several case reports have been published on the use of sugammadex in patients with neuromuscular disorders that include neuromuscular junction diseases, myopathies, neuropathies, and motor neurone disorders. The primary aim of this review is to systematically review the evidence on the use of sugammadex in patients with this heterogeneous group of diseases and provide recommendations for clinical practice. Methods A systematic electronic search of Medline, Embase and CINAHL databases was done until June 2019, to identify case reports describing the use of sugammadex in adult surgical patients with neuromuscular disorders. Results Of the 578 records identified through database searches, 43 articles were finally included for the systematic review. Of these, 17 reports were on patients with myopathy, 15 reports on myasthenia gravis, 9 reports on motor neuron diseases and 2 reports on neuropathies. Conclusions Majority of the articles reviewed report successful use of sugammadex to reverse steroidal muscle relaxants, especially rocuronium, in patients with neuromuscular diseases. However, with sugammadex, unpredictability in response and uncertainty regarding optimum dose still remain issues. Quantitative neuromuscular monitoring to ensure complete reversal and adequate postoperative monitoring is strongly recommended in these patients, despite the use of sugammadex.

Comparison of the Neuromuscular Profile of the First Dorsal Interosseous Muscle and the Flexor Hallucis Brevis Muscle as Measured by Electromyography

Lower limb muscles recover faster than upper limb muscles following administration of nondepolarizing neuromuscular relaxants until the train-of-four ratio (TOFR) reached 0.7. However, no study has been conducted to evaluate the recovery time of the flexor hallucis brevis muscle (FHBM), up to a TOFR of 0.9, which indicates satisfactory recovery of neuromuscular blockade. The aim of this study was to determine electromyographically the relationship between the TOFRs of the FHBM and the first dorsal interosseous muscle (FDIM), following 0.1 mg/kg of vecuronium. Eighteen patients were enrolled in this study. Electromyography of the FDIM and the FHBM was monitored. Onset times and recovery times to TOFRs of 0.7 and 0.9 of both muscles after administration of vecuronium were measured. The onset time in the FDIM was not different from that in the FHBM ( = 0.10). Recovery time to TOFR 0.7 was significantly faster in the FHBM than in the FDIM ( < 0.013). There was no significant difference in the meantime to reach TOFR 0.9 between the FDIM and the FHBM ( = 0.11). There is no clinical importance in the difference of neuromuscular recovery between the FHBM and the FDIM after TOFR reached 0.9 following administration of vecuronium.