Keywords: horse; thoracoscopy EN horse thoracoscopy 125 127 3 02/09/23 20230301 NES 230301 Thoracoscopy in the horse is useful for both diagnostic procedures and minimally invasive access to the thorax for surgical procedures. The benefits of general anaesthesia include improved visualisation of the ventral lung surfaces, ventral thoracic cavity, diaphragmatic surfaces and the lateral surface of the heart (Klohnen & Peroni, [5]). Rapid initiation of IPPV is utilised to reduce severity of hypoxaemia, because once anaesthesia is induced, relative hypoxaemia can result from ventilation-perfusion mismatching, and shunt development may occur (Shawley & Mandsager, [13]). Standing thoracoscopy is utilised under a lighter plane of anaesthesia with the horse placed in stocks, avoiding the risks of general anaesthesia and the need for positive pressure ventilation and insufflation. [Extracted from the article]