Pleuropulmonary and cardiovascular consequences of thoracoscopy performed in healthy standing horses.

The research investigates the impacts of thoracoscopy, a minimal invasive surgical procedure, on cardiopulmonary function in healthy horses. The conducted experiments found no significant negative effects on the horses’ heart and lung function and observed no postoperative complications within 48 hours of the procedure.

Research Design and Methodology

• The study was conducted on six healthy, stand-up, medicinally restrained mature horses with the intent to define changes in cardiopulmonary function during and after exploratory thoracoscopy, as well as to identify any postoperative complications within a 48-hour period post thoracoscopy.
• Using a randomized 3 x 3 Latin square design with two replications, a total of 18 procedures were performed which consisted of six right and six left thoracoscopies, and six sham procedures.
• Prior to each procedure, a physical examination and a bronchoalveolar lavage fluid analysis were carried out. As each experimentation took place, data was collected at six different time intervals and an endoscopic thoracic examination was conducted during the two pneumothorax periods.

Findings and Interpretation

• The data showed that heart rate, respiratory rate, and cardiac output all decreased following the administration of detomidine (a drug used to sedate horses).
• The study also revealed a slight tendency for cardiac output to be lower during the thoracoscopy process itself and detected mild systemic hypertension associated with thoracoscopy.
• The experiment further found that thoracoscopy led to an additional increase in systemic and pulmonary vascular resistances, especially during the second time of pneumothorax.
• An interesting observation was that arterial oxygen tension decreased following detomidine administration and decreased further during the second pneumothorax. Furthermore, oxygen tension was lower when thoracoscopy was performed on the left than the right hemithorax.
• However, within the first 48 hours following the thoracoscopy procedure, there were no significant complications identified. There was a minor postoperative pneumothorax observed in two horses, one of which had a lung laceration caused by the trocar, a surgical instrument.

Conclusion

• In conclusion, thoracoscopy performed on healthy horses that were awake and medicinally restrained was found to not have detrimental effects on cardiopulmonary functions and also didn’t cause significant postoperative complications within the study’s observation period of the first 48 hours after the procedure.