Took Barokko to the clinic yesterday. I brought M along to ride him in the work test. The test was to see how his pulse and respiration evolved when he was worked, and to provoke irritation so she could see him under pressure.
The work test was simple, first the vet listened to his heart and lungs, measured pulse and respiration at rest. She heard a slight "something" in his lungs, but it was very faint at rest. Then 10 mins of forward trot, listen and measure again, and another 10 minutes of forward trot. It was a really hard test for Barokko, already after the first 2 minutes he asked to please stop, and he had to be pushed, pushed, pushed the rest of the time to keep him in trot. He was sooooo tired at the end :(
His pulse and respiration rates were acceptable for a horse out of work, not alarming in themselves. But as he was worked he developed a clear squeaking sound in his lungs, a sign of constriction in the lower airways.
Immediately after the work test he was endoscoped. As expected, his upper airways looked fine, just slightly red from irrittion, but no mucous, and no anatomical abnormalities anywhere. She took a new BAL sample, to be absolutely sure there's no new infection - with long term irritation and constriction of the airways he's much more prone to catching infections than a healthy horse - but she agrees that the problems he has now asre not due to an infection, if he has contracted a new infection then it's secondary.
So if it's not a mechanical issue in the upper airways, it's not an auto-immune irritation, and it's not an active infection, we're left with the worst possible option left - physical damage of the lower airway tissues. My vet got a hold of a vet in the US who is an expert on pseudomonas, and what he had to tell her wasn't good news. Pseudomonas pneumonias are not only sneaky to discover and hard to get rid of, they also tend to leave a mess behind once they're finally eradicated. He said that if the lung capacity of horses who had had pseudomonas pneumonias had been tested before and after, he'd expect every single one of them to be diminished. It's not a question of
did they leave any damage behind, but of
how much.
The plan now is to bring him back into work while he receives a bronchodilator. He's to be worked 4-5 times/week for the next 2-3 months to increase his fitness level, before she can properly assess how damaged his lungs are. She still has a slim hope that by working him on a bronchodilator, and getting him back up to a good aerobic fitness level he'll be able to
overcome the effects of the damage the pseudomonas have wreaked and be able to function as a sports horse afterward, although he may need to be medicated to do so. However, the most probable outcome is that he will not ever be able to be ridden normally again :(