Influence of recumbency upon the incidence of pulmonary shunt in inhalation-anaesthetized sheep

• Grant number: 18/15165-9
• Support Opportunities: Scholarships in Brazil - Master
• Start date: November 01, 2018
• End date: October 31, 2020
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Clinics and Surgery
• Agreement: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: Adriano Bonfim Carregaro
• Grantee: Roberto Romano do Prado Filho
• Host Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil

Abstract

Animal experimental models are widely used on scientific research. Amongst them, ovine are frequently chosen for biomedical research and biomaterial testing, since it reproduces clinical conditions similar to humans. During general inhalation anaesthesia, these animals suffer a pulmonary shunt secondary to the pressure on the diaphragm exerted by their abdominal organs. This condition occurs when the oxygenation of the pulmonary alveoli is inadequate, although correctly perfused, resulting in hypovolemia and hypoxemia. The present study aims to analyze the impact of different decubitus in sheep during inhalation anaesthesia, prioritizing ventilatory changes and pulmonary shunt. For this purpose, 7 sheep of both gender will be submitted to inhalation anesthesia using isoflurane 1.3 MAC, maintained on pressure-controlled ventilation (10 mmHg), with respiratory rate (f) fixed on 12 mpm and a zero end-expiratory pressure (ZEEP). Immediately after anesthetic induction, the animals will undergo one of three different treatments, namely: dorsal, left lateral or right lateral recumbency positions. The order of treatments will be determined randomly, being all animals subjected to all treatments, with duration of 120 minutes each and an interval between treatments of, at least, 15 days. Arterial and venous blood samples will be collected for hemogasometry and hemogram analysis immediately after anesthetic induction, after 60 minutes of induction and after 120 minutes of induction. The results obtained will be used to calculate the pulmonary shunt fraction using a pre-established mathematical model. It is expected to determine a decubitus that favors minimal intercurrences during ventilatory evaluations.

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)

ROBERTO ROMANO DO PRADO FILHO; MARIANA CARDOSO SANCHES; ADRIANO BONFIM CARREGARO. Influência do decúbito na ocorrência de shunt pulmonar em ovinos anestesiados com sevoflurano. Ciência Rural, v. 52, n. 11, 2022-04-29. (18/15165-9)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

PRADO FILHO, Roberto Romano do. Influence of recumbency upon pulmonary shunt occurrence in inhalation-anaesthetized sheep. 2021. Master's Dissertation - Universidade de São Paulo (USP). Faculdade de Zootecnica e Engenharia de Alimentos (FZE/BT) Pirassununga.