A catheter adapted for use in passing fluids and medicines therethrough for use in the perfusion or reperfusion of blood or blood-fluid mixtures into the arteries, veins, tissues, conduits, or organs of a patient by selectively adjusting the flow rate of fluid supplied to a drug delivery lumen of the catheter based at least in part on the sensed systemic fluid pressure and the sensed fluid pressure at a distal end of the catheter is disclosed.