Incidence of muscle pain after short-acting relaxants; a comparison between suxamethonium chloride and suxamethonium bromide

Suxamethonium-induced muscle pains are not related to cholinesterase activity

We have investigated the possibility of using the pre-operative measurement of cholinesterase activity to predict the postoperative development of myalgia following the administration of suxamethonium. Seventy-seven patients presenting for elective extraction of wisdom teeth were entered in the study. All patients received a standard anaesthetic regimen, including suxamethonium to facilitate tracheal intubation, and standardised postoperative analgesia. Myalgia was assessed postoperatively and no correlation between muscle pains and cholinesterase activity was found.

Prevention of succinylcholine-induced myalgia with lidocaine pretreatment

We studied the effects of 3 mg.kg(-1) lidocaine iv on the succinylcholine (SCh)-induced myalgia in 94 unpremedicated ambulant patients undergoing dilatation and curettage of the uterus. The post-SCh myalgia was confirmed through interview by telephone. The data were correlated with the degree of fasciculation and changes in the serum electrolytes and creatine kinase (CK) levels following SCh administration. Pretreatment with lidocaine, 3 mg.kg(-1) iv, significantly reduced the incidence of myalgia from 40.4% of control group to 12.8% lidocaine-treated group, but not the CK levels. The severity of myalgia was not related to the intensity of fasciculation assessed by visual observation. The pretreatment with lidocaine had no untoward effect on the circulation, although the peak arterial and peak venous lidocaine levels achieved were 29.6 +/- 23 micro g.ml(-1) and 10.1 +/- 3.3 micro g.ml(-1) respectively. These finding indicated that the pretreatment with lidocaine, 3 mg.kg(-1) iv, was effective in prevention of SCh-induced myalgia.

The influence of thiopentone and alfathesin on succinylcholine-induced fasciculations and myalgias

Thiopentone doses corresponding to 5.238 mg x kg-1, that is 2UD95 (UD95:unconsciousness dose 95) inhibit the intensity of succinylcholine-induced fasciculations compared with UD95. Alfathesin doses corresponding to 0.570 mg x kg-1, also 2UD95 (calculated as alphaxalone at a concentration of 9 mg/ml in alfathesin), do not have any greater effect on the degree of fasciculations compared to UD95. Furthermore, neither induction agent influences the incidence, distribution and duration of succinylcholine-induced myalgias. The inhibition of the degree of fasciculations caused by thiopentone is believed to be a consequence of a postsynaptic depressant effect of thiopentone at the neuromuscular junction. The evaluation of the degree of succinylcholine-induced fasciculations must take into consideration the dose of thiopentone administered at induction of anaesthesia.

Suxamethonium fasciculations: a topographical study

It has been found in a group of 455 gynaecological patients that not all the voluntary muscles of the body respond to suxamethonium in the same way. One group of muscles (e.g. biceps) which is sensitive to suxamethonium, responds by fasciculating in almost every individual. A second, resistant, group of muscles (e.g. pectoralis major) is almost totally unresponsive to suxamethonium. A third muscle group (e.g. triceps) shows fasciculations in about 60% of cases and appears intimately associated with the development of suxamethonium pains, for if fasciculations do occur then suxamethonium pains are likely to ensure, but not necessarily involving all the fasciculating muscles. A theory to account for these different groups has been proposed involving the known variation in distribution of red and white muscle fibres throughout the body.

The avoidance of suxamethonium pain: a study of patients presenting for laparos copy

A comparison was made of the incidence of post-operative pain in patients given suxamethonium modified by pre-treatment with a small dose of gallamine and those not given suxamethonium. Sequential analysis of the results showed a preference for anaesthetic techniques not employing suxamethonium.