[Objective measurements of airway resistance in recurrent nerve paralysis and hypotonic dysphonia]

Respiratory obstructions of the glottis may be reliably diagnosed at any time with a body plethysmograph used in pulmonary function testing. While respiratory resistance at 27.1 mm H2O/l and sec was only slightly increased in 35 patients with unilateral recurrent nerve paralysis and not even perceived by most of them, considerably increased resistance was found in 65 patients with bilateral paralysis. Critical lifeendangering obstructions of the respiratory system were not observed. Intra- and extralaryngeal lateral fixations of the vocal cord were carried out in 29 subjects. We observed unrestricted breathing and alveolar ventilation with respiratory resistance of 25 to 44 mm H2O/l and sec even under physical strain. Additional optimal phoniatric results and speech function is present in this range. 14 patients operated according to the endolaryngeal method of Thornell 1948 showed the best functional results. In cases of unilateral recurrent paralysis and hypotonic dysphonia we were able to measure the glottic resistance during phonation by using the modified interruption technique. The values were clearly subnormal at a median of 65 to 79 mm H2O/l and sec. In 43 cases treated with teflon injections a 50% increase of the airway resistance during phonation was observed. These findings correlate with the positive subjective experiences of the patients.