Effect site concentrations of remifentanil and pupil response to noxious stimulation

Opioid drugs block reflex pupillary dilatation in response to noxious stimulation. The relationship between the target effect site concentration (CeT) of remifentanil and the pupil diameter and reactivity in response to a standard noxious stimulus were evaluated. Anaesthesia was induced with propofo...

Full description

Saved in:

Bibliographic Details
Published in:	British journal of anaesthesia : BJA Vol. 91; no. 3; pp. 347 - 352
Main Authors:	Barvais, L., Engelman, E., Eba, J.M., Coussaert, E., Cantraine, F., Kenny, G.N.
Format:	Journal Article
Language:	English
Published:	Oxford Elsevier Ltd 01-09-2003 Oxford University Press Oxford Publishing Limited (England)
Subjects:	Adult Aged anaesthetics i.v anaesthetics i.v., propofol analgesics opioid analgesics opioid, remifentanil Analgesics, Opioid - blood Analgesics, Opioid - pharmacology Anesthesia Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy Anesthetics, Combined - pharmacology Anesthetics, Intravenous - blood Anesthetics, Intravenous - pharmacology Biological and medical sciences Dose-Response Relationship, Drug Electric Stimulation Electroencephalography - drug effects eye eye, pupil size eye, reflexes Female General anesthesia. Technics. Complications. Neuromuscular blocking. Premedication. Surgical preparation. Sedation Hemodynamics - drug effects Humans Male Medical sciences Middle Aged Monitoring, Intraoperative - methods Piperidines - blood Piperidines - pharmacology propofol Propofol - pharmacology Pupil - drug effects pupil size Reflex - drug effects reflexes Remifentanil anaesthetics i.v., propofol eye, pupil size eye, reflexes analgesics opioid, remifentanil anaesthetics i.v., propofol; analgesics opioid, remifentanil; eye, pupil size; eye, reflexes Human Intravenous administration General anesthesia Opiates Narcotic analgesic remifentanil; eye Remifentanil Eye Pupil Analgesia reflexes anaesthetics i.v General anesthetic Activity concentration relation Dilatation pupil size; eye Pupillary reflex Propofol Monitoring propofol; analgesics opioid
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	Opioid drugs block reflex pupillary dilatation in response to noxious stimulation. The relationship between the target effect site concentration (CeT) of remifentanil and the pupil diameter and reactivity in response to a standard noxious stimulus were evaluated. Anaesthesia was induced with propofol TCI to obtain loss of consciousness (LOC) in 12 ASA I/II patients. Thereafter, remifentanil CeT was titrated by increments of 1 up to 5 ng ml−1. In the awake state, at LOC and at each plateau level of remifentanil CeT, arterial pressure, heart rate, and BIS (A2000) were recorded. Pupil size and dilatation after a 100 Hz tetanic stimulation (T100) were measured at LOC and at each plateau level of remifentanil CeT. LOC was observed at a mean propofol CeT of 3.53 (sd 0.43) μg ml−1. Arterial pressure and heart rate decreased progressively from LOC to 5 ng ml−1 remifentanil CeT without any statistical difference between each incremental dose of remifentanil. Mean BIS values decreased from 96 (2) in the awake state, to 46 (12) at LOC (P<0.05) and then remained unchanged at all remifentanil CeT. Pupil dilatation in response to 100 Hz tetanic stimulation decreased progressively from 1.55 (0.72) to 0.01 (0.03) mm and was more sensitive than pupil diameter measured before and after 100 Hz tetanus. An inverse correlation between pupil dilatation in response to 100 Hz tetanus and an increase in remifentanil CeT from 0 to 5 ng ml−1 was found (R2=0.68). During propofol TCI in healthy patients, the decrease in pupil response to a painful stimulus is a better measurement of the progressive increase of remifentanil CeT up to 5 ng ml−1 than haemodynamic or BIS measurements.
Bibliography:	Corresponding author. E‐mail: lbarvais@ulb.ac.be local:aeg178 Accepted for publication: April 28, 2003 ark:/67375/HXZ-7R15T45W-Q istex:43183CE616E9331C0225D066E27F90602DA3DE66 ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23
ISSN:	0007-0912 1471-6771
DOI:	10.1093/bja/aeg178