Pulmonary function tests in the diagnosis of upper respiratory tract obstruction

Abstract The results of small spirometry, airway resistance and flow volume loop were compared in 10 patients with upper airway obstruction, 11 patients with chronic pulmonary obstructive disease and 15 healthy examinees. Our results have shown that for detection and differentiation of upper airway obstruction and chronic obstructive pulmonary disease the most reliable values give the following parameters and relations: MIF 50% less than or equal to 100 l/min, MEF 50% greater than or equal to 1, FEV1/ /PEF greater than or equal to 10 ml/l/min, FEV1/FEV0.5 greater than or equal to 1.5 and FEV1/ /FEV1 greater than or equal to 1.