THE TREATMENT OF POSTANESTHETIC SHIVERING - A DOUBLE-BLIND COMPARISONBETWEEN ALFENTANIL AND PETHIDINE

It has been postulated that pethidine may mediate its effects on posta naesthetic shivering (PAS) via kappa-opioid receptors. However, clinic al evidence indicates that alfentanil, a pure mu-agonist, may also hav e beneficial effects on PAS. In order to assess whether opioid effects on PAS are effected via kappa receptors, fifty-one patients were rand omised to receive alfentanil 250 mu g (n=18), pethidine 25 mg (n=18) o r placebo (n=15) on a double-blind basis for the treatment of establis hed postanaesthesia shivering (PAS). Both drugs proved significantly b etter in treating PAS than placebo (P<0.005). Following treatment, blo od pressure fell and oxygen saturation increased in patients in the tw o treatment groups when compared with the control group (P<0.05). Ther e was a highly significant incidence of reshivering in the alfentanil treated group (P<0.005). In conclusion, the high incidence of reshiver ing indicates that alfentanil is unlikely to supercede pethidine in th e treatment of PAS, but its initial success rate implies that pethidin e's anti-shivering effect is unlikely to be mediated via kaPPa-opioid receptors.