RT Journal Article
SR Electronic
T1 Effects of a non opioid analgesic on experimental work/effort dyspnea in healthy volunteers: A laser-evoked potential study
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP P3976
VO 42
IS Suppl 57
A1 Laurence Dangers
A1 Louis Laviolette
A1 Beny Charbit
A1 Thomas Similowski
A1 Capucine Morélot-Panzini
YR 2013
UL http://erj.ersjournals.com/content/42/Suppl_57/P3976.abstract
AB Background. Counter-irritation is the attenuation of a painful sensation by a newly occurring heterotopic stimulus that must be noxious in nature. Dyspnea-pain counter-irritation, arising from C-fibers stimulation, has been described with experimental dyspnea of the work/effort type, which inhibits laser evoked cortical potentials (LEPs). Thus, an experimental dyspnea (work/effort) might be relieved by a non-opioid analgesic. Dyspnea-induced counter irritation should then be attenuated, with a lesser degree of LEPs inhibition.Methods. In this randomized, double-blind, placebo-controlled cross-over study, a non opioid analgesic (nefopam) was administrated by intravenous infusion over 30 min to fifteen healthy naïve male subjects, according to power calculations based on available results. The N2P2 component of LEPs was obtained using CO2 laser stimulation on the hand and recorded using EEG. LEPs were acquired during three conditions: spontaneous breathing, spontaneous breathing under nefopam/placebo and experimental dyspnea induced by inspiratory threshold loading under nefopam/placebo.Results. The intensity of experimental dyspnea was not different (p=0.88) between nefopam and placebo (VAS rating 3.7 ± 2 cm versus 4 ± 1.9 cm). The amplitude of N2P2 during experimental dyspnea was reduced by 35 ± 18% and 25 ± 21 % (Δ = 37%, p = 0.23) with placebo and nefopam respectively (power 0. 74).Conclusion. There was no statistically significant effect of nefopam on experimental dyspnea and on dyspnea-pain counter-irritation assessed by LEPs, but the study proved underpowered. How interfering with C-fibers function could alleviate dyspnea should be further studied.