Clinical meaning
Mechanical circulatory support (MCS) devices augment or replace native cardiac function in patients with severe heart failure or cardiogenic shock. Intra-aortic balloon pumps (IABP) provide counterpulsation -- inflating during diastole to augment coronary and systemic perfusion, and deflating during systole to reduce afterload and myocardial oxygen demand. Continuous-flow LVADs (HeartMate 3, HeartWare) use centrifugal or axial flow pumps to move blood from the left ventricle to the aorta, providing 3-10 L/min of flow; patients may have diminished or absent arterial pulsatility, making traditional blood pressure measurement unreliable (MAP is measured by Doppler). MCS complications include pump thrombosis (hemolysis, elevated LDH), driveline infection (erythema, drainage at exit site), right ventricular failure (JVD, edema, hepatic congestion), hemorrhagic stroke (from anticoagulation), GI bleeding (from acquired von Willebrand syndrome from shear degradation of vWF multimers), and aortic insufficiency. The nurse monitors pump parameters (speed, flow, power, pulsatility index), performs driveline exit site care using sterile technique, monitors INR for warfarin anticoagulation, measures blood pressure using Doppler method, monitors for hemolysis markers, and provides patient and family education about device management, emergency procedures, and activity guidelines.