Mechanism of injection pain with long and longmedium chain triglyceride emulsive propofol

Abstract

P Pu ur rp po os se e: : t has been suggested that long-medium chain triglyceride (LCT/MCT) emulsive propofol causes less injection pain than long chain triglyceride (LCT) emulsive propofol because of the decreased propofol concentration in the aqueous phase. Alternatively, LCT propofol generates bradykinin causing the injection pain and activates complement, but these effects when using LCT/MCT propofol have not been examined. To identify the mechanism for reduced pain with LCT/MCT propofol, injection pain, bradykinin generation and complement activation with use of both propofol products were compared.M Me et th ho od ds s: : Two hundred adult patients randomly allocated to two groups were given 1.5 mg·kg -1 iv of either LCT propofol or LCT/MCT propofol at a rate of 200 mg·min -1 in a double-blind manner and were asked to grade pain scores. In another study, bradykinin and activated complement 3 (C3a) concentrations were measured using blood obtained from 13 healthy volunteers mixed with saline, LCT propofol or LCT/MCT propofol.R Re es su ul lt ts s: : There was a significant difference in pain scores between groups, showing a lower incidence of injection pain in the LCT/MCT propofol group. The bradykinin concentrations in blood mixed with LCT and LCT/MCT propofol were significantly higher than in blood mixed with saline. The C3a concentrations showed similar results.C Co on nc cl lu us si io on ns s: : LCT/MCT propofol causes less pain on injection compared with LCT propofol. Bradykinin generation and complement activation are similar with both LCT and LCT/MCT propofol. Thus, the reason for less pain on injection with LCT/MCT propofol may be attributed to a decreased concentration of propofol in the aqueous phase. Objectif : On a pensé qu'une émulsion de propofol avec une chaîne mi-longue de triglycéride (CLT/CMT) cause moins de douleur à l'injection qu'une émulsion à chaîne longue (CLT) parce que la concentration de propofol diminue pendant la phase aqueuse. Aussi, le propofol avec CLT génère de la bradykinine, causant de la douleur à l'injection, et active le complément, mais ces effets n'ont pas été étudiés avec le propofol CLT/CMT. Pour définir le mécanisme qui réduit la douleur avec le propofol CLT/CMT, nous avons comparé la douleur à l'injection, la génération de bradykinine et l'activation du complément avec l'usage des deux produits de propofol. Méthode : Deux cents patients adultes ont été répartis au hasard en deux groupes et ont reçu 1,5 mg·kg -1 iv de propofol CLT ou CLT/CMT

Influence of polyvinyl chloride infusion extension tube on propofol injection pain

“…Some authors have reported that the use of larger veins, such as the antecubital vein, result in less propofol injection pain. 27,28 However, most studies in the literature have involved the use of a vein in the dorsum of the hand, 1,3,5,17 and it was for this reason that we used this site of injection. However, it is a reasonable assumption that a rapid jet of propofol impinging on the endothelium of a small vein may influence injection pain.…”

Caracterização anestésica da nanoemulsão não lipídica de propofol

“…The pharmacological mechanism of pain-induced by propofol is still unknown 21 . It has been hypothesized involvement of kallikrein-kinin-bradykinin cascade 22,23 . Another hypothesis is related to directly chemical activation of nociceptors induced by propofol on the vascular endothelium 24 .…”

A Clinical Study to Compare the Efficacy of Pretreatment with Granisetron and Lignocaine to Alleviate Pain on Propofol Injection

“…[8] The initial component of pain, involving immediate stimulation of nociceptors and free nerve endings [7] seems to be associated mainly with the concentration of free drug within the aqueous phase of the emulsion. [11] The delayed component of pain, appearing within half a minute, is also believed to result from interaction with nociceptors and free nerve endings [7]; however, promoted by local vasodilatation and hyperpermeability induced by bradykinin [12], [13] and possibly also prostaglandin E2. [10], [12].…”