Comparison of atracurium and "mini-dose" succinylcholine for preventing succinylcholine-induced muscle fasciculations: a randomized, double-blind, placebo-controlled study.

Unlabelled: Several drugs have been used to prevent or attenuate succinylcholine- induced muscle fasciculations. There are possible advantages to succinylcholine pretreatment. We designed the present study to compare the effectiveness of atracurium versus "mini-dose" (5 mg) succinylcholine pretreatment for the prevention of muscle fasciculations.

Methods: Under standard monitoring, 79 patients were randomly assigned to three groups after premedication: Group 1 (n = 26) received normal saline as a placebo, Group 2 (n = 27) received 0.03 mg/kg atracurium, and Group 3 (n = 26) received 5 mg succinylcholine. Thiopental (4 mg/kg) was administered intravenously 90 seconds after pretreatment, followed by intravenous administration of 1.5 mg/kg succinylcholine. An anesthesiologist graded fasciculations based on a four-point scale, from 0 (none) to 3 (severe). All patients were evaluated on the first postoperative day for the presence of postoperative myalgia (POM), the severity of which was graded on a four-point scale, from 0 = no myalgia to 3 = generalized, severe discomfort.

Results: There were no statistical differences among the three groups with respect to sex, weight or age. In Group 1, 3.8% of the patients showed no fasciculations, while 30.8% had mild, 53.8% had moderate and 11.5% had vigorous fasciculations. In Group 2, fasciculations were absent in 74.1% of the patients, while 25.9% of the patients had mild fasciculations. In Group 3, 23.1% patients had no fasciculations, while 42.3%, 30.8% and 3.8% of the patients showed mild, moderate and vigorous fasciculations, respectively, with succinylcholine pretreatment. There was no difference in the presence or severity of myalgia between Groups 1 and 3. Furthermore, the presence of fasciculations was not correlated with POM in Groups 1 and 3, but a significant correlation was found in Group 2.

Conclusion: Our results showed that the incidence and severity of fasciculations were significantly decreased by atracurium pretreatment but not by pretreatment with succinylcholine or placebo (p<0.0001 and p=0.0003 respectively). However, atracurium did not exert significant effects on POM.