Technique and cell differential in bronchoalveolar lavage of horses with COPD

The bronchoalveolar lavage (BAL) is a diagnostic procedure in older foals a nd horses with chronic lung disease. Eleven horses with chronic mild airway disease were sedated (xylacine 0.7 mg/kg i.v., detomidine 30 mu g/kg i.v.) . A sterile 2 m flexible endoscope with a diameter of 12 mm was passed thro ugh the nasal passage, larynx, trachea to the carina and wedged the 4th med ial stem bronchus. In a trial before the infusion of 300 ml of ink fluid th rough the described endoscope in the wedged 4th bronchus showed the biggest distribution of parenchymal staining. Before we passed the carina 10 ml of xylocain (2%) were deposed to reduce coughing. 300 to 400 ml of saline wer e infused and aspirated immediately with 50 ml syringes. Lavage fluid of 10 0 to 200 ml were collected. The second, third and fourth sample in 50 mi sy ringes were mixed and used for cytology. The polymorph nucleated cells (24- 56%), eosinophils (2-9%) and the epithelial cells (7-32%) in BAL fluid of h orses with mild small airway disease were increased. In two horses a pulmon ary eosinophilia was detected (2-5% polymorph nucleated cells, 16-33 per ce nt lymphocytes, 2-9 per cent macrophages, 47-61 per cent eosinophils, 9-16 per cent epithelial cells). These horses were 4 and 9 years old and no para sites in BAL fluid or fetes were detected.