Evaluation of general inhalation anesthesia with isoflurane in pregnant mares positioned in dorsal decubitus and in reverse Trendelenburg position and the influence on the fetus

• Grant number: 21/13378-8
• Support Opportunities: Regular Research Grants
• Start date: May 01, 2022
• End date: April 30, 2024
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Clinics and Surgery
• Principal Investigator: Renata Gebara Sampaio Dória
• Grantee: Renata Gebara Sampaio Dória
• Host Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil
• Associated researchers: Adriano Bonfim Carregaro ; Carlos Augusto Araújo Valadão ; Luciano Andrade Silva

Abstract

In veterinary medicine, it is often necessary to perform emergency surgical procedures in pregnant animals. In these cases, fetal monitoring during the anesthetic procedure is rarely performed and, currently, there are several opinions about which method would be the most suitable for this follow-up. During general inhalational anesthesia in pregnant mares, there are risks that maternal hemodynamic and hemogasometric changes may compromise uteroplacental perfusion and/or fetal oxygenation, increasing the risk of miscarriages or premature births. In human medicine, in most cases, adequate fetal monitoring is not performed, but monitoring through ultrasound and the presence of an obstetric team ready to intervene when they identify fetal distress is recommended. Generally, only emergencies and elective surgeries that do not pose a risk to the fetus are performed, avoiding, as much as possible, general anesthesia in pregnant women. When possible, the preference for performing the procedure is in the middle third of pregnancy. In the case of horses, conditions such as acute abdomen are often surgical emergencies, requiring general inhalational anesthesia in pregnant mares at different gestational stages, already with systemic changes arising from the disease involved. In these cases, the main parameter available to assess fetal distress is heart rate, which is directly correlated with fetal cardiac output. This project envisages submitting healthy, non-pregnant mares and healthy mares in the initial, middle and final thirds of pregnancy to general inhalational anesthesia with isoflurane, in dorsal decubitus, and performing maternal hemodynamic and hemogasometric evaluations, correlating such data with fetal monitoring data, obtained by ultrasonography in order to predict the effects of the gestational phase on anesthetic risk, both for the mare and the fetus. In addition, the reverse Trendelenburg group will be established in mares in the final third of pregnancy, in an attempt to improve the patient's ventilatory and hemodynamic parameters, in order to improve anesthetic safety at this stage of pregnancy, both for the mare and for the fetus. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

SAMPAIO DORIA, RENATA GEBARA; REGINATO, GUSTAVO MORANDINI; HAYASAKA, YUMI DE BARCELOS; NETO, PAULO FANTINATO; PASSARELLI, DANIELLE; ARANTES, JULIA DE ASSIS. Complications following transcutaneous cecal trocarization in horses with a cattle trocar and a cecal needle. PLoS One, v. 17, n. 11, p. 17-pg., 2022-11-23. (12/00632-4, 21/13378-8)