Morphological substantiation of multimodal analgesia in hyperalgesia treatment
In study 50 non-linear rats and 50 maice with weight of 20-25 g was used. As a model of hyperalgesia carrageenan edema was used (0,1 ml, 1% sol.). Carrageenan edema was modeled by sublantar injection of 0,05ml 1% carrageenan solution (Sigma, USA) in the animal's right hind limb. Obseravtion of the ptostaglandin edema development in animals of both sexes was conducted at the 3rd hour (development pick) after the flogogen injection. Animals was divided into 4 groups. I - carrageenan edema without treatment (control group), animals of the II group was injected fentanyl (5 mcg/kg) intaperitoneally, animals of the III group was ingected bupivacaine (25 mcg/kg, 1-2ml) in the perinevral space, animals of the IV group was injected ketamine. Using of fentanyl in high doses in animals can lead to opioid-induced hyperalgesia, which is accompanied by skin morphological changes after carrageenan injection. On the 3rd hour after fentanyl injection next morphological changes was observed - alteration zone was very spread, without clear borders, with the necrosis development in it's center (thickness of necrosis tissue was under 5 mm) with expressed perifocal reactive changes in the form of significant inflammation (reactive changes zone thickness under 7 mm), significant microcirculation violations took place. Using of local analgesia methods with bupivacaine almost completely negates this changes, and while ketamine using in tissue was observed changes similar to morphological changes after fentanyl infusion, but they were less expressed.