An automatic device for single-breath CO diffusing capacity in dogs.

We describe a very simply operated system by which single-breath CO diffusing capacity (DLCO) can be measured in anesthetized dogs. All controls and the automatic system are operated pneumatically. Cams forming an integral part of the pistons of the inspiratory and expiratory syringes activate push buttons which control the valves, enabling dead spaces to be flushed, a specific volume of air to be injected into the dog's lungs, and expiratory samples to be taken. Our results, due account being taken of the dogs' weight, are in the upper range of normal values published in earlier studies; the reproducibility of the method is good.