Evaluation of a method for assessing pulmonary function in laryngectomees.

In total laryngectomies the impairment of pulmonary function reflects the sum of pre- and post-operative ventilatory changes. Objective information on the respiratory condition in laryngectomees, as assessed in the pulmonary function laboratory is somewhat limited, perhaps because of difficulties related to methodology. The aim of our study was to evaluate the reproducibility of a method employed to assess the pulmonary function in laryngectomized patients. The experimental extra-tracheal device was set up with a silicone adapter through a cardboard tube to the skin around the tracheostoma. Pulmonary function tests included measurements of forced vital capacity, force expiratory volume at 1 second and Tiffeneau index in 3 consecutive evaluations, in 11 patients who underwent total laryngectomy. The control group comprised 11 patients, not laryngectomized, evaluated by conventional spirometry. Those responsible for evaluating were asked to report possible technical failures and to demonstrate the reproducibility of the curves resulting from the tests. The use of the silicone adapter and skin adhesive provided a complete, airtight seal of the system, in all cases. The presence of the tracheo-oesophageal prosthesis did not negatively affect the test results. All patients attributed a maximum value, both for comfort and acceptance, of the device. The values are comparable in both groups, thus indicating the accuracy of the proposed methodology. All examinations were reproducible. After total laryngectomy, pulmonary function testing, with an extra-tracheal device, is not only reliable but also easy to perform in a routine out-patient setting. The methodology did not present air leaks and was, therefore, well accepted by all patients tested.