BACKGROUND The influence of alfentanil on the pharmacokinetics of propofol is poorly understood. Therefore, the authors studied the effect of a pseudo-steady state concentration of alfentanil on the pharmacokinetics of propofol. METHODS The pharmacokinetics of propofol were studied on two occasions in eight male volunteers in a randomized crossover manner with a 3-week interval. While volunte...

Alfentanil 35 micrograms kg-1, was used successfully in a patient with severe aortic stenosis, in order to minimize the haemodynamic responses to intubation and surgery during Caesarean section. The baby was delivered apnoeic, unresponsive and with poor muscle tone, but responded rapidly to naloxone. Plasma alfentanil concentrations and percentage binding to plasma proteins were measured in bot...

Intubating conditions under halothane anaesthesia aided with alfentanil 20 micrograms.kg-1 were compared with suxamethonium 2 mg.kg-1 in 40 children presenting for day dental procedures. The condition of vocal cords, jaw relaxation and presence of movement and coughing were scored to give the overall intubating conditions. Successful intubation was achieved in 100% of the suxamethonium group an...

Alfentanil has a short duration action which did not markedly increase with increasing dose in mice. It is approximately one-fourth as potent as fentanyl. Repeat injections gave reproducible analgesic effects but depression of respiratory rate increased when repeat injections were given on the basis of cessation of analgesic activity. Alfentanil appeared to reduce the analgesic effect of morphi...

BACKGROUND The primary aim of the present study was to determine the dose of alfentanil that must be added to a rapid-sequence induction (RSI) regimen using thiopentone and rocuronium to obtain optimal intubation conditions in >95% of the individuals. METHODS A total of 60 ASA I patients were randomly allocated to five different alfentanil dose groups (0, 15, 30, 45, or 60 microg kg-1). A bli...

UNLABELLED This study examined the effects of an esmolol infusion on the electroencephalogram during propofol/alfentanil IV anesthesia. After informed consent, 20 patients were randomly assigned into four groups on the basis of two target alfentanil concentrations (alfentanil 50 or 150 ng/mL) and of a saline or esmolol infusion. Bispectral index (BIS), burst suppression ratio (SR), and physiolo...

Background: Patient-controlled sedation (PCS) is increasingly used for moderate sedation. Detailed understanding is essential for maintaining safety and giving the most benefit. We wanted to explore the associations between patients’ characteristics, perioperative pain and anxiety, the procedure, and the calculated concentrations at the effect site (Ce) of propofol. We also wanted to analyse th...

We have investigated if alfentanil acts via peripheral opioid receptors to relieve the pain which occurs on injection of propofol. Thirty seconds before induction of anaesthesia and immediately after a tourniquet at 50 mm Hg greater than systolic pressure was inflated on the upper arm, patients were given either placebo (n = 22), alfentanil 1 mg (n = 22) or lignocaine 40 mg (n = 22) via an i.v....

We have studied plasma protein binding of alfentanil in 10 patients given a mean total dose of 949 micrograms kg-1 as the principal anaesthetic agent for coronary artery bypass grafting. The mean unbound fraction of plasma alfentanil increased from 0.09 to 0.16 after administration of heparin and to 0.26 after beginning cardiopulmonary bypass (CPB). After CPB until the end of surgery, the unbou...

This prospective double-blind study compared the effectiveness of EMLA with alfentanil and placebo in reducing the overall pain during ophthalmic nerve blocks. Seventy-five patients scheduled for cataract surgery were divided into three groups. Patients in the EMLA group had EMLA cream applied over skin areas corresponding to injection sites for retrobulbar and facial nerve blocks one hour befo...