Mamoru Hasegawa

The McGill Pain Questionnaire, Japanese version, reconsidered: confirming the theoretical structure.

BACKGROUND Based on a tripartite theoretical model of pain, the Pain Rating Index (PRI) of the McGill Pain Questionnaire (MPQ) continues to be one of the most frequently used instruments to measure clinical pain. However, language and cultural barriers have hindered its wide use and standardization in Japan. Although a number of exploratory factor analysis studies have failed to support consistently the theoretical structure of the MPQ, a few previous confirmatory factor analysis studies did statistically support the a priori model. OBJECTIVE To test, through confirmatory factor analysis (CFA), the theoretical structure of a Japanese version of the MPQ (JMPQ), which followed a format similar to that of the original MPQ. DESIGN This study used CFA on prospectively collected data from 199 consecutive outpatients with chronic pain at a university hospital to test the theoretical structure of the JMPQ. RESULTS AND CONCLUSIONS CFA was completed on the first 16 PRI subclass scores; this process yielded a well fitting final model that explained 92% of the covariance in the observed data. The results supported the hypothesis that the sensory, affective and evaluative subscales of the PRI are representative of the multidimensionality of the pain experience, with minimal overlap. It is suggested that the theoretical structure of the MPQ is maintained in the JMPQ used in this study. Therefore, this study is the first step toward standardization of the JMPQ, serving as a cultural bridge in the field of pain medicine between Japan and English-speaking nations such as Canada.

Intrathecal neurokinin-1 receptor antagonist reduces isoflurane MAC in rats

PurposeTo study the effects of intrathecal administration of a neurokinin-l(NK-l) receptor antagonist (CP96.345) on the minimum alveolar anaesthetic concentration (MAC) of isoflurane in anaesthetized rats, and on the locomotive activity of conscious rats.MethodsWistar rats (n = 36) were fitted with indwelling intrathecal catheters, and the MAC of isoflurane was determined following the intrathecal administration of saline (control group) or the NK-1 receptor antagonist CP96.345 (CP) at 1, 10 and 100 μg. Subsequently a reversal dose of intrathecal Substance P (SP) at 1. 10 and 100 μg was administered and MAC isoflurane was redetermined. Conscious rats (n = 35) were also examined for the presence of locomotor dysfunction following intrathecal administration of CP and SP Animals were randomly assigned to each treatment group and the investigators were blinded.ResultsCP at 10 and I00 μg reduced MAC isoflurane by 9.9% and 15.3%, respectively (P < 0.05). Intrathecal administration of SP reversed the decreases in MAC by CP; however, locomotive activity was not changed.ConclusionThese results suggest that the NK-1 receptor plays an important role in determining the MAC of isoflurane by inhibition of pain transmission in the spinal cord.RésuméObjectifÉtudier les effets de I’administration sous-arachnoïdienne d’un antagonize du récepteur neurokinine-I NK-1 le CP96 345) sur la concentration alvéolaire minimum (MAC) de I’isoflurane chez le rat anesthésié et sur I’activité locomotrice chez le rat conscient.MethodesDes cathéters sous-arachnoïdiens ont été implantés chez des rats Wistar (n=36) et le MAC de l’isoflurane déterminé apres I’administration sous-arachnoïdienne de sol. phys. (Groupe contrôle) ou 1, 10 et 100 μg de I’antagoniste du récepteur NK-I, le CP96 346 (CP). Par la suite, une dose sous-arachnoïdienne neutralisante de la substance P (SP) de 1, 10 et 100 μg était administrée et le MAC de I’isoflurane déterminé de nouveau. Chez les rats conscients, on a aussi recherché la présence d’un dysfonctionnement locomoteur après I’administration de CP et de SP Les animaux étaient assignés aléatoirement à chaque groupe de traitement. L’observation des effets etait réalisée à I’aveugle.RésultatsDix et 100 μg de CP diminuaient respectivement le MAC de I’isoflurane de 9,9% et 15,3% (P < 0,05). Ladmimstration sous-arachnoïdienne de SP abolissait les diminutions du MAC provoquées par CP; I’activité lovomotnce demeurait toutefois inchangée.ConclusionCes résultats suggèrent que le récepteur NK-1 influence nettement le MAC de l’isoflurane par inhibition médullaire de la transmission de la douleur.

The McGill Pain Questionnaire - Japanese Version, Reconsidered: Confirming the Reliability and Validity

BACKGROUND: The McGill Pain Questionnaire (MPQ) is one of the most widely used instruments in the world to evaluate patients with chronic pain. However, differences in languages and cultural backgrounds have hindered its standardization in Japan.