An apparatus for monitoring the intra-abdominal pressure of a patient includes a urinary catheter (102) connected to a urine valve (250) providing selectable communication between a discharge end of the urinary catheter (102) and either a drain (224) or a fluid source (104). Preferably, the urine valve (250) is adapted for remote actuation and has a housing adapted to resist patient discomfort from leg-valve (250) contact. Plumbing structure desirably maintains fluid supply (225) and drain (223) conduits in a substantially parallel arrangement to assist routing those conduits (225, 223) between a patient's legs. When the urine valve (250) is oriented to permit communication with the fluid source (104), an infusion pump (116') may be used to infuse a known quantity of fluid through the urine valve (250) and into the patient's bladder (216). A pressure transducer (218) desirably is connected in-circuit to indicate the fluid's pressure and avoid pressure fluctuations induced by system components. To facilitate the infusion process, an automatic flow control device may be included in a fluid supply path (225) and arranged to permit repetitive operation of a syringe (116') to inject a bolus of fluid into the patient's bladder (216). Subsequent to making a pressure measurement, the urine valve (250) is returned to the bladder (216) draining position.