Systems, devices and methods for draining and analyzing bodily fluids are disclosed where one variation of the catheter system may generally comprise a catheter having at least one opening near or at a distal end of the catheter, a barb in fluid communication with a proximal end of the catheter, a drainage tube in fluid communication with the at least one opening, and a vent tube in fluid communication with the barb. A one-way valve may be positioned in-line with the vent tube and at a location proximal to the barb and a controller may be in communication with the one-way valve, wherein the controller is programmed to apply a negative pressure to the drainage tube resulting in the one-way valve being opened and fluid passing through the vent tube.
