Low power laser protects human erythrocytes in an in vitro model of artificial heart-lung machines

The protective effect of the low power helium-neon (He-Ne) laser against th e damage of human erythrocytes in whole blood was examined in a perfusion m odel using an artificial heart-lung machine. Preserved human whole blood wa s diluted and perfused in 2 closed circuits with a double roller pump. The laser irradiated one of the circuits (laser group), and none the other (con trol group). In the laser group, erythrocyte deformability and erythrocyte adenosine triphosphate (ATP) levels were significantly higher, and free hem oglobin levels were significantly lower than those in the control group. Su bsequent morphological findings by means of scanning electron microscope we re consistent with these results. Low power He-Ne laser protected human ery throcytes in the preserved diluted whole blood from the damage caused by ex perimental artificial heart-lung machines. The clinical application of low power laser treatment for extracorporeal circulation is suggested.