Disappearance of Micro‐Emboli Transfused into Patients During Cardiopulmonary Bypass

Upon standing, blood stored in ACD solution develops aggregates of platelets and leukocytes in one to ten days. Blood stored in heparin solution develops the same aggregates in 24 hours or less. When heparinized blood, containing many such aggregates (micro‐emboli) is transfused into patients during employment of the heart‐lung apparatus these micro‐emboli are very rapidly filtered from the blood by the vascular bed of the patient. It is suggested that occlusion of the many small blood vessels which must occur during such procedures is potentially harmful to the patient, and probably contributes to unexplained reactions occurring during and after employment of the heart‐lung apparatus.