Rubin’s test [Isador C. Rubin, American gynecologist, 1883–1958] , a test performed in the process of evaluating the cause of infertility to assess the patency of the fallopian tubes. Also called resistance-inducing factor test. ▪ METHOD: Carbon dioxide gas (CO2) is introduced into the tubes under pressure through a cannula inserted into the cervix. The CO2 is passed through from a syringe connected to a manometer at pressures of up to 200 mm Hg. If the tubes are open, the gas enters the abdominal cavity, and the recorded pressure falls below 180 mm Hg. A high-pitched bubbling can be heard through the abdominal wall with the stethoscope as the gas escapes from the tubes. The patient may complain of shoulder pain from diaphragmatic irritation; an x-ray film will show free gas under the diaphragm. If the tubes are blocked, gas cannot escape from the tubes into the abdominal cavity; the pressure recorded on the manometer remains at 200 mm Hg. A tracing may be made to show tubal peristalsis, any leakage in the system, tubal spasm, or partial obstruction. ▪ PATIENT CARE CONSIDERATIONS: After the test, the patient rests for 3 hours. Crampy pain, dizziness, nausea, and vomiting may occur; positioning with the pelvis higher than the head in genupectoral position or in Trendelenburg’s position allows the gas to stay in the pelvis and gives some relief by avoiding diaphragmatic irritation.
