Stocks J, Costeloe K, Winlove C P, Godfrey S
J Clin Invest. 1977 Mar;59(3):490-9. doi: 10.1172/JCI108664.
An accurate method for measuring effective pulmonary capillary blood flow (Qc eff) in infants has been developed with an adaptation of the plethysmographic technique. Measurements were made on 19 preterm. 14 small-for-dates, and 7 fullterm normal infants with a constant volume whole body plethysmograph in which the infant rebreathed nitrous oxide. There was a highly significant correlation between Qc eff and body weight, and this relationship was unaffected by premature delivery or intrauterine growth retardation. Mean Qc eff in preterm, small-for dates, and fullterm infants was 203, 208 and 197 ml min-1 kg-1, respectively, with no significant differences between the groups. A significant negative correlation existed between Qc eff and haematocrit in the preterm infants. There was no relationship between weight standardized Qc eff and postnatal age in any of the groups. With this technique, it was possible to readily recognise the presence of rapid recirculation (indicative of shunting) in several of the infants, suggesting that rebreathing methods for the assessment of Qc eff should not be applied indiscriminately during the neonatal period. By taking care to overcome the potential sources of technical error, it was possible to obtain highly reproducible results of Qc eff in infants over a wider age range than has been previously reported.
通过对体积描记技术进行改进，已开发出一种测量婴儿有效肺毛细血管血流量（Qc eff）的准确方法。使用恒定容积的全身体积描记仪对19名早产儿、14名小于胎龄儿和7名足月正常婴儿进行测量，婴儿在其中重复呼吸氧化亚氮。Qc eff与体重之间存在高度显著的相关性，且这种关系不受早产或宫内生长迟缓的影响。早产儿、小于胎龄儿和足月婴儿的平均Qc eff分别为203、208和197 ml min⁻¹ kg⁻¹，各组之间无显著差异。早产儿的Qc eff与血细胞比容之间存在显著的负相关。在任何一组中，体重标准化的Qc eff与出生后年龄之间均无关系。使用这种技术，可以很容易地识别出几名婴儿中存在快速再循环（提示分流），这表明在新生儿期不应不加区别地应用重复呼吸法来评估Qc eff。通过注意克服潜在的技术误差来源，有可能在比以前报道的更宽年龄范围内获得婴儿Qc eff的高度可重复结果。
