Exploratory study design of microbubble Contrast-enhanced echocardiography in diagnosing inflammatory-induced pulmonary lesion in horses: adequacy, execution and diagnostic viability

• Grant number: 19/21567-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2019
• End date: November 30, 2020
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Clinics and Surgery
• Principal Investigator: Paulo Aléscio Canola
• Grantee: Maria Luiza Favero
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

Colic syndrome is an important condition related to the horse whose progression can potentially trigger systemic inflammatory response syndrome or sepsis and septic shock, further leading to multiple organ disfunction. Viscera and third space organs such as the lungs are most commonly affected. In sepsis, venous return decreases and, as consequence, portal hypertension develops. As result, intrapulmonary vascular dilatation may occur, further leading to the manifestation of hepatopulmonary syndrome (SHP). This scenario is well known in humans, but not yet observed in horses. In humans, the diagnosis of SHP can be obtained by microbubble contrast-enhanced echocardiography. It seems that, until now, there is no mention of the use of this test in the diagnosis of lesions in horses, especially in the cases of pulmonary injuries resulting from systemic inflammatory conditions. In this context, we sought to adapt and evaluate the feasibility of the microbubble contrast-enhanced echocardiography used in man to the horses, and subsequently, in another study, evaluate the clinical use of the test in order to investigate the occurrence of pulmonary lesions resulting from systemic inflammatory response (SIRS) or sepsis in equine patients. Initially, between 10 and 15 horses will be used. They will be submitted to four distinct treatments: treatments 1 and 2 with infusion of 25 ml of microbubble contrast solution and treatments 3 and 4 with infusion of 60 ml of microbubble solution. Using syringes of appropriate volume, the microbubble solution will be prepared and injected into the left external jugular vein of the subjects. Simultaneously with the ultrasound equipment, the pre-established cardiac cycle interval (beats) (between one and three and between three and five) will be echocardiographically recorded for each specific treatment whilst the microbubble contrast solution is being administrated. After the trial, the best ratio of contrast volume vs the number of cardiac cycles to be used will be determined for horses in similarity to the pre-established determinations for humans. (AU)