A specially trained RN inserts a small catheter, the approximate size of a small pencil eraser, into the rectum. This catheter has transducters located on the end which measures pressures at the rectal sphincter. The nurse performing this procedure then provides the physician with the results for interpretation. The patient is not sedated for this procedure which can take up to 30 - 45 minutes.
Usually the physician will have the patient administer a fleets enema prior to arrival at the hospital.