Clinic of Neonatology (Charité Campus Mitte), Charité Universitätsmedizin, Berlin, Germany.
Med Sci Monit. 2009 Oct;15(10):BR275-280.
Knowledge of lung volume is essential for monitoring and optimizing mechanical ventilation. The aim of this study was to compare lung volume measurements by multiple-breath heptafluoropropane (HFP) washout (MBW) and by respiratory gated computed tomography (CT) in ventilated newborn piglets.
MATERIAL/METHODS: In 6 ventilated piglets (age: <12 h, median weight: 945 g) blood gases, respiratory mechanics, and lung volumes were measured in both the supine and prone positions. The measurements were performed in random order. Functional residual capacity (FRC) was measured simultaneously by HFP MBW (FRC(HFP)) using a new infrared mainstream sensor and by CT (FRC(CT)) at the end of inspiration and expiration (multi-slice Toshiba Aquilon 16, Otawara, Japan). Tidal volume (V(T)) was measured both by the Dräger Babylog 8000 ventilator (V(T BL)) and the volume difference of the CT scans (V(T CT)).
FRC(HFP) (25.2+/-8.5 ml) and FRC(CT) (24.9+/-7.6 ml) correlated strongly (r=0.97) without significant bias. Bland-Altman limits of agreement showed differences between the two methods that ranged from -19.7 to +19.5%. A similar strong correlation without statistically significant bias was found between V(T BL) (8.5+/-2.0 ml) and V(T CT) (9.0+/-2.4 ml) with r=0.91. The limits of agreement were -24.4 and +14.0%. Body position (prone vs. supine) had no significant effect on blood gases, respiratory mechanics, or lung volumes.
Lung volumes measured in small ventilated lungs by HFP washout and CT are highly correlated and independent of body position. However, the relatively large limits of agreement indicate differences in the two techniques.
了解肺容量对于监测和优化机械通气至关重要。本研究旨在比较七氟醚多呼吸法（MBW）和呼吸门控计算机断层扫描（CT）测量在机械通气新生仔猪中的肺容量。
材料/方法：在 6 只机械通气的仔猪（年龄：<12 小时，中位体重：945 克）中，仰卧位和俯卧位时分别测量血气、呼吸力学和肺容量。测量以随机顺序进行。功能残气量（FRC）通过新的红外主流传感器进行 HFP MBW（FRC（HFP））测量，并在吸气和呼气末通过 CT（FRC（CT））测量（多切片东芝 Aquilon 16，大泽，日本）。潮气量（V（T））通过 Dräger Babylog 8000 呼吸机（V（T BL））和 CT 扫描的体积差异（V（T CT））进行测量。
FRC（HFP）（25.2+/-8.5 毫升）和 FRC（CT）（24.9+/-7.6 毫升）相关性很强（r=0.97），无显著偏倚。Bland-Altman 一致性界限显示两种方法之间的差异范围为-19.7 至+19.5%。V（T BL）（8.5+/-2.0 毫升）和 V（T CT）（9.0+/-2.4 毫升）之间也发现了类似的强相关性，无统计学显著偏倚，r=0.91。一致性界限为-24.4 和+14.0%。体位（俯卧位与仰卧位）对血气、呼吸力学或肺容量无显著影响。
通过 HFP 洗脱和 CT 测量，小机械通气肺中的肺容量高度相关，且不受体位影响。然而，相对较大的一致性界限表明两种技术存在差异。
