Abstract: A pump assembly for increasing urine output from a patient includes at least one ureteral catheter including: a distal portion having a retention portion configured to be positioned in a patient's kidney, renal pelvis, and/or ureter; and a proximal portion defining a drainage lumen. The retention portion includes at least one drainage port which permits fluid flow into the drainage lumen. The pump assembly further includes a pump configured to provide negative pressure to at least one of the renal pelvis or kidney through the drainage lumen of the at least one ureteral catheter. The pump includes at least one fluid port in fluid communication with the drainage lumen of the proximal portion of the ureteral catheter for receiving fluid from the patient's kidney, wherein at least a portion of the pump is configured to be positioned within a patient's body.