Apparatus for aiding and improving the blood flow in patients

Abstract

Improved blood pumping apparatus is disclosed which includes a smooth avalvular deflatable section through which blood flows, said section mounted within a rigid avalvular airtight housing, gas being introduced and withdrawn from the housing by suitable control means, the action of the gas causing the blood chamber to inflate and deflate with consequent non-traumatic pulsatile ejection of blood from said chamber. The apparatus is simple, reliable, inexpensive and can aid the blood pumping function in many ways. For example, apparatus is disclosed to provide pulsatile flow to the blood being pumped by a heart-lung machine, or to provide pulsatile flow to the coronary arteries during coronary artery perfusion, or to be utilized as an arterio-venous fistula to decrease the afterload of the left ventricle and preserve the systemic diastolic pressure while increasing coronary perfusion. In addition, apparatus is disclosed which can, with slight modification, function as counterpulsation apparatus to, for example, support a patient's systemic circulation by left heart counterpulsation, or wean a patient off a heart-lung machine when the patient's heart has resumed beating, or support the right heart by pulmonary artery counterpulsation, or provide counterpulsation when other types of counterpulsation, such as intra-aortic balloon pump counterpulsation, are impractical.