title: Comparison of helium dilution and nitrogen washout measurements of functional residual capacity in premature infants.
abstract: Comparison has been made of measurements of functional residue capacity (FRC) by a helium gas dilution (He) and a nitrogen washout (N2) technique. Twenty infants (median gestational age, 29.5 weeks) were studied at a median postnatal age of 25 days. No infant was oxygen dependent. The coefficient of repeatability of FRC (He) was 6.4 mL/kg and of FRC (N2), 6.3 mL/kg. The coefficient of repeatability of the two methods combined was 13.8 mL/kg. In 10 infants the results of two techniques differed by more than 20% of the mean FRC; those infants were born at a significantly earlier gestation than the rest of the cohort (P < 0.01). We conclude that, except in very immature infants, techniques for measuring FRC (He) and FRC (N2) yield reproducible and comparable results in convalescent premature infants.
authors.affiliation: Department of Child Health, King's College Hospital, London, England.
authors.forename: B
authors.initials: B
authors.lastname: Yuksel
authors.forename: A
authors.initials: A
authors.lastname: Greenough
authors.forename: V
authors.initials: V
authors.lastname: Chan
authors.forename: R R
authors.initials: RR
authors.lastname: Russell
mesh_terms: D005260:Female; D005652:Functional Residual Capacity / Q000502:physiology*; D005865:Gestational Age; D006371:Helium; D006801:Humans; D007201:Indicator Dilution Techniques; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature / Q000502:physiology*; D008297:Male; D009584:Nitrogen; D015203:Reproducibility of Results
chemical_list: D006371:Helium; D009584:Nitrogen