Systems, devices and methods for draining and analyzing bodily fluids

A method for draining fluid, comprising:

• positioning a catheter system in proximity to a body of a subject, the catheter system having a catheter with at least one opening near or at a distal end of the catheter, a barb coupled to a proximal end of the catheter, and a drainage tube having a drainage lumen in fluid communication with the at least one opening;
• actuating a controller in communication with a passive one-way valve which is positioned in-line with a vent tube having a vent lumen and which is in fluid communication with the barb, wherein the vent lumen is positioned external to a fluid reservoir and the vent lumen and drainage lumen are separated from one another;
• and
• applying a negative pressure to the drainage tube and the vent tube causing the one-way valve to open by the application of the negative pressure directly upon the one-way valve and fluid passing through the vent tube.