HYDRAULIC POWER ASSOCIATED WITH PULMONARY BLOOD FLOW AND ITS RELATION TO HEART RATE
HYDRAULIC POWER ASSOCIATED WITH PULMONARY BLOOD FLOW AND ITS RELATION TO HEART RATE
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DOI：
10.1161/01.res.19.3.467
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发表时间：
1966-01-01
影响因子：
20.1
通讯作者：
BARGAINE.JD
中科院分区：
文献类型：
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作者：
MILNOR, WR;BERGEL, DH;BARGAINE.JD
对 29 只麻醉狗和 5 只未麻醉狗在不同心率下的肺血管输入阻抗和液压功率进行了测量。测量了 5 只狗的肺静脉-心房交界处的液压功率。未麻醉狗的肺血管阻抗谱与麻醉狗没有显着差异。麻醉犬的平均肺动脉功率为 157 毫瓦 (mw)，其中 108 毫瓦与平均压力和流量相关，49 毫瓦与这些装置周围的脉动相关。百分之七十八的输入功率在通过肺床时消耗掉了。动能占总输入功率的7%。由于阻抗在 0 到 3 周期/秒之间急剧下降，并且流量脉动谐波结构随速率变化，因此对于给定的平均流量（最高 180 次/分钟），心率与输入功率之间存在反比关系。肺血管的尺寸和弹性决定了阻抗，因此体现了一种机制，即心动过速可以使肺血流量增加多达 35%，同时肺动脉输入功率增加不到 5%，而无需血管舒缩活动的干预。
Pulmonary vascular input impedance and hydraulic power were measured at various heart rates in 29 anesthetized and 5 unanesthetized dogs. Hy-draulic power at the pulmonary veno-atrial junction was measured in 5 dogs. The pulmonary vascular impedance spectrum in the unanesthe-tized dogs did not differ significantly from that in the anesthetized dogs. Average pulmonary arterial power in the anesthetized dogs was 157 milliwatts (mw), of which 108 mw was associated with mean pressure and flow, and 49 mw with the pulsations around these means. Seventy-eight per cent of this input power was dissipated in passage through the pulmonary bed. Kinetic energy accounted for 7% of the total input power. Because of a steep fall in impedance between 0 and 3 cycles/sec, and a rate-dependent change in the harmonic structure of flow pulsations, there was an inverse relationship between heart rate and the input power for a given mean flow, up to 180 beats/min. Pulmonary vascular dimen-sions and elasticity, which determine impedance, thus embody a mechanism whereby tachycardia can increase pulmonary blood flow by as much as 35% with an increase in pulmonary arterial input power of less than 5%, without the intervention of vasomotor activity.