Safety and efficacy of a technique for thoracoscopically guided pulmonary wedge resection in horses

OBJECTIVE: To evaluate the safety and efficacy of thoracoscopically guided pulmonary wedge resection in horses. ANIMALS: 10 horses (5 control horses and 5 horses affected with recurrent airway obstruction ie, heaves]). PROCEDURE: Each horse underwent a thoracoscopically guided pulmonary wedge resection. Before, during, and after surgery, heart rate, respiratory rate, arterial blood gases, and systemic and pulmonary arterial pressures were measured. Physical examination, CBC, and thoracic radiography and ultrasonography were performed 24 hours before and 2 and 48 hours after surgery. Pulmonary specimens were assessed by histologic examination. A second thoracoscopic procedure 14 days later was used to evaluate the resection site. RESULTS: The technique provided excellent specimens for histologic evaluation of the lung. Heart and respiratory rates decreased significantly after horses were administered sedatives. A significant transient decrease in Pao2 was detected immediately after pulmonary wedge resection, but we did not detect significant effects on arterial pH, Paco2, or mean arterial and pulmonary arterial pressures. All horses except 1 were clinically normal after thoracoscopic surgery; that horse developed hemothorax attributable to iatrogenic injury to the diaphragm. The second thoracoscopy revealed minimal inflammation, and there were no adhesions. CONCLUSIONS AND CLINICAL RELEVANCE: Thoracoscopically guided pulmonary wedge resection provides a minimally invasive method for use in obtaining specimens of lung tissues from healthy horses and those with lung disease. This technique may be useful for the diagnosis of diseases of the lungs and thoracic cavity.