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

The effect of thiopentone on severity and duration of succinylcholine-induced fasciculation

BACKGROUND

Thiopentone has a protective effect as far as succinylcholine-induced myalgias are concerned; however, a few studies were done in the efficacy of thiopentone on fasciculation induced by succinylcholine. The purpose of this study was to determine the effects of thiopentone on onset, duration, and severity of fasciculation caused by succinylcholine injection.

METHODS

Three hundred patients, in American Society of Anesthesiologists Physical Status Classification I and II, undergoing elective ocular surgery at Farabi Eye Hospital in 2003 were considered and divided into 2 groups who received intravenous succinylcholine immediately and 30 seconds after thiopentone injection, respectively. After premedication and induction of anesthesia, the severity and duration of fasciculations caused by succinylcholine were compared between the 2 groups.

RESULTS

In the group using succinylcholine immediately after thiopentone injection, the onset of fasciculation was earlier (P = 0.0006), and duration of fasciculation was shorter (P = 0.0002) than the other group. In addition, moderate to severe fasciculation was found more in the group using succinylcholine 30 seconds after thiopentone injection (P = 0.038).

CONCLUSIONS

Pretreatment with thiopentone immediately before succinylcholine administration can decrease the duration and severity of fasciculation more than thiopentone injection 30 seconds before succinylcholine administration.

Myalgia in outpatient surgery: comparison of atracurium and succinylcholine

We studied 60 outpatients randomly divided into two groups. Anesthesia was induced with fentanyl 1.5 micrograms.kg-1 plus thiopentone 5-7 mg.kg-1. Patients in Group I were intubated with the aid of succinylcholine 1.5 mg.kg-1 after pre-treatment with d-tubocurarine 0.05 mg.kg-1. Group II received atracurium 350 micrograms.kg-1 three minutes after a priming dose of 50 micrograms.kg-1. Anesthesia was maintained with isoflurane 1-2 per cent in a mixture of nitrous oxide 60 per cent and oxygen 40 per cent. No supplemental doses of fentanyl or atracurium were given. Intubation conditions were satisfactory for all patients in both groups. There was no significant difference in intubation score between the two groups. The incidence of myalgia was 76 per cent in the succinylcholine group compared to 23 per cent in the atracurium group (p less than 0.005). Fifty per cent of the patients in the succinylcholine group had myalgia necessitating bed rest or analgesics compared to 23 per cent in the atracurium group (p less than 0.05). We conclude that atracurium is a suitable neuromuscular relaxant for outpatient surgery and that myalgia is a major morbidity factor in this population that can be reduced by the use of atracurium instead of succinylcholine.

Failure of two benzodiazepines to prevent suxamethonium-induced muscle pain

In a randomised double-blind trial carried out on fit, unpremedicated patients undergoing standard minor operations with early postoperative mobility, using a standard form of anaesthesia, pretreatment with diazepam 0.15 mg/kg or midazolam 0.1 mg/kg failed to reduce significantly the incidence of postoperative muscle pains following suxamethonium 1 mg/kg. By contrast, tubocurarine 0.05 mg/kg proved to be effective as a pretreatment. Neither benzodiazepine influenced the incidence or severity of fasciculations seen with suxamethonium or the duration of neuromuscular block. Tubocurarine virtually abolished visible fasciculation and, in the dose used, reduced the intensity and duration of the neuromuscular block. There were no clinically significant changes in serum potassium, creatinine phosphokinase or aldolase after suxamethonium, although 5 out of 47 showed an atypical rise in creatinine phosphokinase.