[Pharmacology and mechanism of action of opiates administered by the subarachnoid route].
The sites of action of spinally administered opiates are specific receptors (mu kappa delta) located in the spinal dorsal horn. Pharmacokinetics of spinally administered opiates are determined by their lipophilic property. Morphine has a weak octanol-water partition coefficient and remains in the CSF during a long period following the cephalic movements of lumbar CSF to the supraspinal structures. More lipophilic opiates are rapidly eliminated from the CSF. Nevertheless, significant pethidine concentrations are documented in the ventricular CSF, due to vascular absorption of the drug. Pharmacokinetics features of different opiates determine the duration of analgesia and the risk of respiratory depression after spinal injection.
Département d'Anesthésie-Réanimation III, Hôpital Henri Mondor, Créteil.
F
F
Bonnet
L
L
Delaunay
N
N
Liu
D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology*; D006801:Humans; D007278:Injections, Spinal; D011957:Receptors, Opioid / Q000187:drug effects*
D000701:Analgesics, Opioid; D011957:Receptors, Opioid
Pharmacologie et mode d'action des opiacés administrés par voie sous-arachnoïdienne.