肺泡压升高对狗右心室收缩性能的影响

INFLUENCE OF ELEVATED ALVEOLAR PRESSURE ON RIGHT VENTRICULAR CONTRACTILE PROPERTY IN DOG

用肺泡加压法单纯增加狗的右心室后负荷发现,当肺泡压轻度增加时,右心室收缩力增加,而左心室收缩力、流量、左房压和舒张期冠脉灌注压差不变;当肺泡压升至1.5kPa时,右心室收缩力开始下降,左心室收缩力下降更明显,流量、舒张期冠脉灌注压差下降和右房压增加。故本实验提示:①右心室后负荷增加时,左心室并没有进一步加强心室间的偶联作用帮助右心室克服后负荷。②右心室收缩性能对血流动力学的稳定有重要意义,当其不耐后负荷时会引起血流动力学的紊乱。

When right ventricular afterload is increased in six open thoracic dogs, it is found that when alveolar pressure is elevated to 1.0 KPa or less, RV + dp/dt rises and LV + dp/dt is unchanged; that when the pressure is elevated to 1.5 KPa, RV + dp/dt begins to lower and LV + dp/dt is significantely decreased. The disorder of blood dynamics appeares. The experiment suggests( 1 )when right ventricular afterload is increased, left ventricle do not help right ventricle to overcome the afterload by the double action of two ventricles; (2) right ventricular contractile property be of importance in sustainig the steadiness of blood dynamics, and if it cannot ovecome the afterload, disorder of blood dynamics will be its result.