devices systems and methods are disclosed for preventing or inhibiting secretions from entering the lumen of a functional assessment catheter for the lungs , or removing collected secretions . the catheter comprises an expandable element , a cover , or an internal component configured to prevent or inhibit secretion flow into the lumen . the catheter alternatively or additionally comprises a distal end configured to facilitate air flow , absorb secretions or repel secretions away from the catheter tip . the catheter alternatively or additionally comprises an internal element such as a coilable wire , or an obturator configured to prevent secretions from being drawn into the lumen , or to actively remove the secretions . the catheter alternatively or additionally comprises an element to dry , aerate or aspirate the lung passageways .