Urology & Urogynecology > Education and Reference

The one procedure performed in the upper urinary tract is the WHITAKER TEST and is primarily performed by pediatric urologist or nephrologists.

The purpose of the Whittaker Test is to diagnose the presence of a functional ureteral obstruction. This is accomplished by measuring the pressure differential between the renal pelvis and the bladder.

Setup:

1. Urodynamic system with a pre-configured procedure with 2 pressure channels (p1 and p2). The configuration could also utilize a subtracted pressure channel if available.

2. Set an infusion rate appropriate for the patient ( ADULT: 12 – 18 ml/min, PEDI: 8 – 10 ml/min)

3. Assemble associated hardware and supplies for pressures and infusion pump. 2-dual lumen urodynamic catheters.
 - Infusion solution is usually isotonic saline and contrast medium.
 - Infusion is performed under direct fluoroscopic observation.

Procedure:

1. A percutaneous nephrostomy is performed, placing a dual lumen catheter into the renal pelvis. a. Close the cap on the pressure lumen when urine return is noted. b. Connect the fill lumen to the contrast infusion tubing.
2. Insert a second catheter into the bladder, via the urethra. a. Close the cap on the pressure lumen of this catheter, or allow to drain into a receptacle until connected to pressure transducer. b. Cap the fill lumen, if a dual lumen catheter.
3. Start the Whittaker test procedure on the urodynamic system, permitting transducers to zero to atmospheric pressure. 4. Connect the pressure lumen of the catheter in the renal pelvis to p2 transducer on Life-Tech urodynamic system (this channel will likely bear the pabd label). 5. Confirm that the fill lumen of the renal catheter is connect to the infusion pump tubing. 6. Begin recording the procedure. 7. Begin infusion. It is recommended that infusion start at the low end of the range for the patient and gradually increase to maximum.

Results:

The test result can be calculated manually or viewed on a subtracted pressure channel. The Whittaker Test is considered POSITIVE (for functional ureteral obstruction) when the differential pressure (p1 minus p2) is GREATER THAN 15cmH2O.