We have studied dose-dependent effects of alfentanil, fentanyl and morphine on mid-latency auditory evoked potentials (MLAEP). Anaesthesia was induced with alfentanil 100 micrograms kg-1 every 5 min to a total dose of 500 micrograms kg-1 (group I, n = 10), fentanyl 10 micrograms kg-1 every 7 min to a total dose of 50 micrograms kg-1 (group II, n = 10) or morphine 1 mg kg-1 for induction and 0.5...

BACKGROUND In animals, systemic and intrathecal administration of the alpha2 -adrenergic receptor agonist dexmedetomidine results in robust antinociceptive effects in models of heat pain. In humans, systemically administered dexmedetomidine is approved for sedating patients in the intensive care unit. However, whether systemic administration of dexmedetomidine in humans produces significant ana...

BACKGROUND Methadone disposition and pharmacodynamics are highly susceptible to interactions with antiretroviral drugs. Methadone clearance and drug interactions have been attributed to cytochrome P4503A4 (CYP3A4), but actual mechanisms are unknown. Drug interactions can be clinically and mechanistically informative. This investigation assessed effects of the protease inhibitor indinavir on met...

OBJECTIVE To compare 8% or 5% sevoflurane and propofol induction according to the ease of laryngeal mask airway (LMA) placement and hemodynamic effects in elderly patients. METHODS Ninety unpremedicated American Society of Anesthesiologists (ASA) I-III male patients >65 years, undergoing day case urological surgical intervention under general anesthesia at the Numune Education and Research Ho...

The incidence of postoperative nausea and vomiting and requirements for anti-emetic medication were assessed in 80 female patients undergoing day-case anaesthesia during assisted conception therapy. Anaesthesia was induced with alfentanil 50 micrograms.kg-1 and propofol 1 mg.kg-1; atracurium 0.5 mg.kg-1 was given to facilitate tracheal intubation. The patients were allocated to receive either t...

OBJECTIVE Laryngoscopy and tracheal intubation may cause significant cerebral and systemic hemodynamic responses. Many drugs have been shown to be effective in modifying these hemodynamic responses, including fentanyl, sufentanil, alfentanil and remifentanil. The purpose of the current study was to compare the efficacy of fentanyl, sufentanil, alfentanil and remifentanil on blunting cardiovascu...

BACKGROUND AND OBJECTIVES Sedation-analgesia is recommended for comfortable colonoscopy procedures, which are invasive and can be painful. This study aimed to compare the combinations of propofol-alfentanil and propofol-fentanyl for sedation-analgesia in elective colonoscopy patients. METHODS This prospective and randomized study was planned in ASA I-II groups and included 80 patients between...

BACKGROUND Methadone clearance is highly variable, and drug interactions are problematic. Both have been attributed to CYP3A, but actual mechanisms are unknown. Drug interactions can provide such mechanistic information. Ritonavir/indinavir, one of the earliest protease inhibitor combinations, may inhibit CYP3A. We assessed ritonavir/indinavir effects on methadone pharmacokinetics and pharmacod...