Factors that influence cutaneous reactions following administration of thiopentone and atracurium.

Atracurium was administered by a variety of techniques to determine whether these influence the onset or duration of muscular relaxation, and the frequency of cutaneous reactions, after a standard induction dose of thiopentone. One-hundred-and-fifty patients were allocated randomly to receive the drug by one of five methods: into a fast-flowing crystalloid infusion in the antecubital fossa; into a winged needle in the antecubital fossa with flushing after the thiopentone; into a winged needle in the antecubital fossa without flushing; into a winged needle in the dorsum of the hand without flushing. The above groups received atracurium freshly removed from the refrigerator whereas the fifth group were given atracurium which had been maintained at room temperature for at least 2 weeks. The frequency of cutaneous reactions was between 60 and 70% overall and there were no significant differences either in this or in the onset or duration of action between the groups. A further 25 patients with a history of drug allergy were also investigated by the first method and showed no significant differences in response, but 25 patients aged over 70 years had a significantly lower frequency of cutaneous reactions with a higher frequency of hypotension than the other groups.