A Clinical Study of Sensitivity to Sodium Nitroprusside during Controlled Hypotensive Anesthesia in Young and Elderly Patients

Publisher Website
Google Scholar
Abstract
The purpose of this study was to examine the effects of alfentanil applied to the surface of the spinal cord and the effects of intravenously administered alfentanil on noxiously evoked activity of dorsal horn neurons. Extracellular single neuron recordings were obtained from wide dynamic range neurons in 26 decerebrate cats with transected spinal cords. Spinally administered alfentanil, 25 μg or 50 μg, caused 36 and 86% suppression of noxiously evoked activity, respectively. Maximum mean suppression was achieved at 24 and 21 min after 25 μg and 50 μg, respectively. Intravenous naloxone, 0.1 mg, when tested, completely reversed the suppression. Spontaneous recovery to control values occurred within 2 hr. Intravenously administered alfentanil, 12.5 μg/kg or 25 μg/kg, produced suppression of 43 and 89%, respectively, with maximum mean suppression observed at the 6- and 3-min time points, respectively. Complete recovery after intravenous administration was seen within 30 min. This study, using a sensitive neurophysiologic assay, demonstrates the important differences in onset and duration of drug effects that must be considered when comparing the responses of spinal cord neurons to intravenously administered narcotics and narcotics applied directly to the surface of the spinal cord.

This publication has 0 references indexed in Scilit: