Effect of right ventricular bypass peak flow-rate on intrapulmonary shunt ratio.
The effect of total right ventricular bypass peak flow-rate on the intrapulmonary shunt ratio was quantitatively investigated in animal tests. To give variations in the peak flow-rate (from pulsatile to intermediate to non-pulsatile), three types of blood pump (piston-bellows, screw, and centrifugal) were applied to dogs. The intrapulmonary shunt ratio was calculated from blood oxygen content drawn every 30 min from the outlet of the right ventricular bypass pump and from the femoral artery, while the canine lung was ventilated with 100% oxygen gas by an artificial respirator. The results show that when the intrapulmonary shunt ratio ranged between 0.095 and 0.392 there is no clear relation to the peak-flow-rate index (which varied from 1.1-17.0 l min-1 m-2) over the preceding 30 min. This study demonstrates that the intrapulmonary shunt ratio is able to be kept within the range of control values for 6 h even with a peak-flow-rate index of less than 4.0 l min-1 m-2.
Hashimoto
S
S
Department of Bioengineering, School of Medicine, Kitasato University, Sagamihara, Japan.
Moriya
H
H
D000818:Animals; D002315:Cardiopulmonary Bypass; D003326:Coronary Circulation; D004285:Dogs; D006352:Heart Ventricles; D006355:Heart-Lung Machine; D011652:Pulmonary Circulation; D011673:Pulsatile Flow