Allen J L, Greenspan J S, Deoras K S, Keklikian E, Wolfson M R, Shaffer T H
Department of Pediatrics, St. Christopher's Hospital for Children, Philadelphia, PA 19134-1095.
Pediatr Pulmonol. 1991;11(1):37-43. doi: 10.1002/ppul.1950110107.
Asynchronous or paradoxic motion between the rib cage and abdomen may be seen in infants with lung disease. We have recently shown that after bronchodilator administration, the degree of asynchrony decreases proportionately to the improvement in lung mechanics. However, whether such thoraco-abdominal asynchrony (TAA) is a useful indicator of lung function in a cross-sectional population, i.e., whether asynchrony correlates with baseline lung mechanics, is unknown. Therefore, we quantitated the degree of TAA using respiratory inductive plethysmography during quiet sleep in ten infants with bronchopulmonary dysplasia (BPD) and six weight-matched control infants. We displayed abdominal wall (AB) and rib cage (RC) motion on an X-Y recorder, and from the tidal breathing loop we calculated a phase angle phi, between 0 degrees and 180 degrees as an index of asynchrony (synchronous RC/AB motion = 0 degrees, paradox = 180 degrees). Lung resistance (RL) and compliance/kg (CL/kg) were calculated from esophageal and mouth pressure, tidal volume, and tidal flow. As expected, BPD infants had abnormally high RL, and low CL/kg when compared to controls. All infants with BPD displayed marked thoraco-abdominal asynchrony (phi = 102 +/- 16 degrees, mean +/- SEM; range 35 degrees-160 degrees) with controls displayed synchronous chest wall motion (phi = 8 +/- 3 degrees, range 0 degrees-15 degrees) (P less than 0.001). The degree of TAA was significantly correlated with RL (r = 0.773, P less than 0.001) and inversely correlated with CL/kg (r = -0.67, P less than 0.01). We conclude that in infants of similar weight, TAA may be used as a cross-sectional index reflecting both resistive and elastic properties of the lungs.
患有肺部疾病的婴儿可能会出现胸廓与腹部之间的异步或反常运动。我们最近发现，在给予支气管扩张剂后，异步程度会随着肺力学的改善而成比例降低。然而，在横断面人群中，这种胸腹部异步（TAA）是否是肺功能的有用指标，即异步是否与基线肺力学相关，尚不清楚。因此，我们使用呼吸感应体积描记法对10名支气管肺发育不良（BPD）婴儿和6名体重匹配的对照婴儿在安静睡眠期间的TAA程度进行了量化。我们在X-Y记录仪上显示腹壁（AB）和胸廓（RC）运动，并从潮气呼吸环中计算出0度至180度之间的相位角φ作为异步指数（同步RC/AB运动 = 0度，反常 = 180度）。根据食管和口腔压力、潮气量和潮气流计算肺阻力（RL）和每千克顺应性（CL/kg）。正如预期的那样，与对照组相比，BPD婴儿的RL异常高，CL/kg低。所有BPD婴儿均表现出明显的胸腹部异步（φ = 102 ± 16度，平均值 ± 标准误；范围35度 - 160度），而对照组表现出同步胸壁运动（φ = 8 ± 3度，范围0度 - 15度）（P < 0.001）。TAA程度与RL显著相关（r = 0.773，P < 0.001），与CL/kg呈负相关（r = -0.67，P < 0.01）。我们得出结论，在体重相似的婴儿中，TAA可作为反映肺的阻力和弹性特性的横断面指标。
