Analgesic and psychomotor effects of thiopental at subanesthetic concentrations in human volunteers.

摘要: Background: Studies of the effects barbiturates on modulation pain have produced mixed results. In a prospective, double-blind, randomized, placebo-controlled trial, we studied thiopental at presumed steady-state, “conscious sedation” levels cold-pressor-induced in 12 healthy volunteers. Methods: Five drug conditions were used, each condition consisting an injection (either or placebo) with 20-min infusion and 160-min recovery period. The placebo (saline), targeted to three effect-site concentrations, fentanyl (1.4 μg/kg), as positive control verify test sensitivity analgesic drugs. concentrations modeled (STANPUMP) achieve 5, 7.5, 10 μg/ml using bolus three-step continuous infusion. minutes into period 115 min after was terminated, subjects immersed their forearms ice cold water for 3 while behavioral assessments recorded. Results: Thiopental highest dose significant reduction (P< 0.05) self-reported intensity both 5 termination Fentanyl reduced during first immersion only. changed subjects' moods psychomotor performance dose-related fashion. Conclusions: Our laboratory results do not support long-held belief that are “antanalgesic” hyperalgesic, least pain.