Cardiovascular evaluation of the effects of inhalational anesthesia on capybaras (Hydrochoerus hydrochaeris) submitted to contraceptive surgery by the open conventional or videolaparoscopic techniques

• Grant number: 19/14875-5
• Support Opportunities: Regular Research Grants
• Duration: April 01, 2020 - June 30, 2022
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Clinics and Surgery
• Principal Investigator: Silvia Renata Gaido Cortopassi
• Grantee: Silvia Renata Gaido Cortopassi
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated researchers: Mario Antonio Ferraro Rego ; Priscila Rocha Yanai

Abstract

Capybara is a rodent, host of the tick Amblyomma sculptum and potential disseminator of Brazilian Spotted Fever. By adapting easily to diverse environments and having a high reproductive capacity, the population control of some groups of capybara may be necessary, and the most appropriate methods, considering the hierarchical characteristics of the species and the pathogenesis of spotted fever, are the vasectomy and tubal ligation. Given the difficulties in anesthetic maintenance, the lack of literature related to anesthesia in this species and the fact that video-surgical techniques generally have advantages over conventional open correspondents, the objective is to compare the cardiovascular parameters of the use of inhalational anesthesia between conventional and video-surgery for salpingectomy and deferentectomy procedures in capybaras and the surgical trauma resulting from these two different techniques. Twenty-eight capybaras will be distributed into two groups according to the proposed surgical technique and everyone will receive the same anesthetic protocol with ketamine (7 mg / kg) and dexmedetomidine (6 mcg / kg) and maintained with isoflurane. Cardiac, respiratory, analgesic and quality functions in the postoperative recovery, size of the incision, time of the procedure and surgical complications will be evaluated. Heart rate (HR) and rhythm, systolic blood pressure (BP), rectal temperature, respiratory rate (RR), end-expired dioxide tension (ETCO2 - mmHg) as well as inspiratory and expired concentrations of isoflurane and the inspired fraction of oxygen (FIO2 -%), oxyhemoglobin saturation in the peripheral blood (SpO2) every 10 minutes until the beginning of the anesthetic recovery. Samples of arterial blood will be collected at the moment after intubation and at the end of the surgical procedure, in order to obtain the values of arterial hydrogenation potential (pH), arterial carbon dioxide partial pressure (PaCO2 - mmHg), partial pressure of arterial blood oxygen concentration (PaO2 - mmHg), plasma bicarbonate ion concentration (HCO3 - mmol / L), and baseline deficits (BE - mmol / L) . Variations in leukogram, acute phase proteins, cortisol, noradrenaline and plasma glucose will also be measured. It is expected that the use of inhalational anesthesia will be used more frequently in the performance of surgical procedures in capybaras, and that the use of the videolaparoscopic approach presents less surgical trauma when compared to the open technique. (AU)