{'fraction_non_alphanumeric': 0.049800796812749, 'fraction_numerical': 0.037848605577689244, 'mean_word_length': 4.646067415730337, 'pattern_counts': {'":': 0, '<': 1, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Comparison of helium dilution and nitrogen washout measurements of functional residual capacity in premature infants

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. Pediatr Pulmonol. Pediatr Pulmonol. 1993; 16:197–200. © 1993 Wiley‐Liss, Inc.