Harken A H
J Thorac Cardiovasc Surg. 1975 Aug;70(2):237-41.
The possible advantages of pulsatile over continuous blood flow have intrigued cardiac surgeons for years. This issue may have clinical significance for moderate to long cardiopulmonary bypass procedures. In spite of aggressive investigation, this problem remains controversial. A system permitting perfusion of an isolated canine hind limb with constant flow, Pao2, Paco2, oxygen delivery, temperature, and pHa but variable stroke volume was established. Under stable conditions, oxygen uptake by the limb was constant over a wide range of stroke volumes. Regression equations relating oxygen uptake to stroke volume were calculated and found to have a near zero slope. When the hydrogen ion concentration of the blood perfusing tissue is held constant, the oxygen consumption of that tissue is independent of the pulsatile nature of the perfusing blood.
多年来，搏动血流相对于连续血流可能具有的优势一直吸引着心脏外科医生。这个问题对于中度至长时间的体外循环手术可能具有临床意义。尽管进行了积极的研究，但这个问题仍然存在争议。建立了一个系统，该系统允许以恒定流量、动脉血氧分压（Pao2）、动脉血二氧化碳分压（Paco2）、氧输送、温度和动脉血pH值（pHa）但可变的每搏量灌注孤立的犬后肢。在稳定条件下，在很宽的每搏量范围内，后肢的氧摄取量是恒定的。计算了氧摄取量与每搏量之间的回归方程，发现其斜率接近零。当灌注组织的血液氢离子浓度保持恒定时，该组织的氧消耗与灌注血液的搏动性质无关。
