A method of delivering a therapeutic and/or diagnostic agent to tissue is provided including the steps of inserting a catheter into a bodily cavity, the catheter having a proximal balloon and a distal balloon, inflating the proximal and distal balloons to create a chamber between the proximal and distal balloons, delivering the therapeutic and/or diagnostic agent to the chamber, measuring fluid pressure in the chamber, measuring at least one fluid dynamic characteristic of a subject, and adjusting the delivery of the therapeutic and/or diagnostic agent based at least in part on the measured volumetric pressure in the chamber and the at least one fluid dynamic characteristic of the subject.