Spirometric indices in the assessment of laryngeal obstruction.
To determine if spirometric indices allow detection and quantification of a laryngeal obstruction, we obtained oro-laryngeal airway resistance (Ro1) and several spirometric indices in 43 patients with various laryngeal diseases. Assuming Ro1 greater than or equal to 0.2 kPa/(1/s) to imply a laryngeal obstruction, the highest sensitivity was found for FIV1 = 2.0 1 (forced inspiratory volume in one second) being about 84% at a specificity of about 88%. The highest correlation coefficients (r = 0.72-0.83) were obtained between Ro1 and MIF50/MEF50 (the ratio between maximum expiratory and inspiratory flow at 50% of vital capacity) and between I/Ro1, and PIF (peak inspiratory flow), MIF50 and FIV1. In conclusion spirometric indices allow detection of a laryngeal obstruction in the majority of cases, but do not appear adequate for a quantitative assessment in an individual patient.
D000293:Adolescent; D000328:Adult; D000368:Aged; D000403:Airway Resistance; D005260:Female; D006801:Humans; D007320:Inspiratory Capacity; D007829:Laryngostenosis / Q000175:diagnosis*; D008297:Male; D008448:Maximal Expiratory Flow Rate; D008875:Middle Aged; D010366:Peak Expiratory Flow Rate; D013147:Spirometry; D014826:Vocal Cord Paralysis / Q000175:diagnosis*