Determination of lung volume by hydrogen dilution at the time of underwater weighing

• Published in: Nutrition research (New York, N.Y.) Vol. 6; no. 10; pp. 1139 - 1145
• Main Authors: Pasco, J.A., Rutishauser, I.H.E., Read, R.S.D.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.10.1986; Elsevier Science
• Subjects: Air breathing; ANALISIS; ANALYSE; Biological and medical sciences; body composition; COMPOSICION DE LA CANAL; COMPOSITION DE LA CARCASSE; densitometry; Fundamental and applied biological sciences. Psychology; HIDROGENO; hydrogen; HYDROGENE; lung volume; MEDICION DEL CUERPO; MENSURATION CORPORELLE; POUMON; PULMONES; Respiratory system: anatomy, metabolism, gas exchange, ventilatory mechanics, respiratory hemodynamics; Vertebrates: respiratory system; VOLUME; VOLUMEN; body composition; hydrogen; densitometry; lung volume; Human; Measurement; Lung volume; Hydrogen; Densitometry; Method; Respiratory system; Body composition
• ISSN: 0271-5317; 1879-0739
• DOI: 10.1016/S0271-5317(86)80084-7

A method for measuring the volume of air in the lungs at the time of underwater weighing is described. A low concentration of hydrogen is used as a tracer gas in a closed-circuit rebreathing system. At the end of a normal exhalation the subject is connected to a respiratory bladder containing 2 L of air with a small admixture of hydrogen. After an equilibration period of five breaths the subject submerges completely, together with the bladder, and underwater weight is measured. Lung volume, at the time of weighing, is determined by hydrogen dilution. Using this method, the coefficient of variation for body density in the same individual was 0.23%.