Anestesia dissociativa e mediação inflamatória de asininos sob vulnerabilidade submetidos à orquiectomia

Abstract

This research presents the results from field inguinal orchiectomies of vulnerable donkeys, removed from slaughter in the state of Bahia, evaluating dissociative anesthesia and inflammatory mediation. During the trans-surgical period, the research aimed to evaluate dissociative anesthesia combined with testicular local anesthesia, measuring the anesthetic quality, recovery time and applicability. Animals were selected, kept in an extensive system (without any supplementation), in the municipality of Canudos, with clinical and laboratory tests within the normal range. The anesthetic protocol performed was the same for all animals, and consisted of pre-anesthetic medication with xylazine (1 mg\kg IV); local block with 2% lidocaine in the testicular parenchyma; induction with ketamine (2 mg/kg) and midazolam (0.4 mg/kg) and positioned in dorsal decubitus, with inguinal orchiectomy performed. Heart rate (HR) and respiratory rate (RR) were measured during and after surgery. Anesthetic quality assessment was performed based on variables defined in the work, classifying sedation, induction and anesthetic maintenance by scores (0-3). The proposed protocol did not lead to significant physiological changes during anesthesia of an average surgical procedure of sixteen minutes related to orchiectomy. However, it was noted that a third of the animals did not present sufficient sedation with the dose of xylazine used, which may have caused a lower resistance in anesthetic induction in almost a quarter of the sample and the need for reinforcement in anesthetic maintenance in 40% of the donkeys. . From the research, the safety of the described protocol is proven, with further research needed to see if increasing the triple-drip infusion rate would not bring better anesthetic quality in physiological effects not satisfactory to the species. During the postoperative period, the research aimed to evaluate pain, physiological variations and acute phase proteins in donkeys. The animals were evaluated in relation to physiological parameters, behavioral assessment of pain through a scale, hematological parameters and PFA, in addition to the evaluation of the surgical wound, during 0h, 24h, 48h and 72h. As for the physiological parameters and PFA, no significant differences were observed between the times, due to the proteins of this electrophoretic assay being of late acute phase, therefore, the times were not enough to detect the beginning of the alterations, which will start from 72 hours. In the Macroscopic evaluation of the surgical region, it was observed that there were no significant differences between the times, with animals presenting mean scores of 1.8±0.414, in 48 hours 1.6±0.507, and in 72 hours 1.6±0.507. Even so, most animals had mild to moderate edema in the scrotum and foreskin regions, even with the use of anti-inflammatory drugs and local anesthetics to minimize inflammation as much as possible. As for pain assessment, the average sum of scores of the animals was between 2-3, representing mild and moderate pain, not requiring intervention. However, further research is needed to elucidate the behavior of PFA in the face of variables and the creation of new pain scales for the field reality, since it is the reality of most donkeys raised in Brazil, which are raised in an extensive system and spend entire postoperative process.