Tilt Table Test
A Tilt Table Test is designed to evaluate how your body regulates blood pressure in response to gravitational challenge. Blood pressure is regulated by a set of nerves, which operate continuously and subconsciously and are part of the autonomic nervous system. This set of nerves detects certain bodily needs and they respond by causing appropriate changes in blood pressure. The purpose of this part of the autonomic nervous system is to insure that there is always enough blood going to the brain, and to distribute blood to other organs according to their needs. For example, during exercise, blood is delivered preferentially to the muscles, whereas during eating blood is delivered preferentially to the intestines. These changes in blood pressure are accomplished by making changes in the way the heart beats and by making changes in the caliber or size of certain blood vessels. At times, the nerves which control blood pressure may not operate properly and may cause a reaction that causes the blood pressure to drop suddenly. This reaction may produce a fainting spell or a number of symptoms including severe lightheadedness. Tilt table testing is designed to determine the likelihood that a patient is susceptible to this type of reaction.
Who Needs a Tilt Table Test: Patients that have symptoms suggestive of a sudden drop in blood pressure may benefit from the evaluation of blood pressure regulation with a tilt table test. The tilt table test was originally designed to evaluate patient with fainting spells because a drop in blood pressure causes many fainting spells. Tilt table testing may also be useful for patients who have symptoms of severe lightheadedness or dizziness, which don’t actually cause them to faint, but force them to sit down or lie down.
What to Expect: The first part of the study evaluates how blood pressure responds to the simple stress of standing up, or in other words how blood pressure responds to the stress of gravity. Patients are asked to remove their clothing above the waist, put on a hospital gown, and lie down on a special table. Two safety straps are placed around your waist and knees. Patients are connected to an electrocardiogram (ECG), have a small cuff placed around the arm to measure blood pressure, and have a small intravenous line (IV) placed into a vein. Once everything is set up, baseline blood pressure and ECG data is obtained while you lie quietly on the table. Once baseline data is obtained, the table will tilt at different angles for different periods of time. It is important to report any symptoms of feeling lightheaded, nausea, dizzy, palpitations (fluttering in the chest), blurred vision, or feelings of faint. For those who do not experience a drop in blood pressure after 45 minutes, the table is returned to a flat position. The second part of the tilt table test (which is not always performed) evaluates how blood pressure responds to a stress caused by a medication that is very much like your body’s own adrenaline. Adrenaline is a hormone that is produced when you exercise or when you are angry or feel stress. The medication used is called Isuprel and produces the same effects as adrenaline. A small amount of Isuprel is infused slowly and is increased if necessary according to how your heart responds. You will feel your heart beating a little faster and stronger. Once the appropriate dose of Isuprel is infused, the table will be tilted to a 60-degree angle for 15 minutes. If no symptoms of drop in blood pressure occur, the table will be returned to a flat position. Many patients who have a positive test feel a little unsettled and sometimes queasy for the first few minutes after the test. The vast majority of patients will return to feeling completely normal within 5 to 10 minutes after the test. Most patients are able to drive home after the test. However, the test can be tiring, so individuals who live a distance from the testing site, may prefer that someone drive them home. The test usually takes one to two hours.
Preparation: Patients should not eat or drink after midnight prior to the test. You are able to take your medications with sips of water. However, patients that have diabetes should check with the testing center to verify whether they should or should not take their diabetic medication. Very few medications actually interfere with a tilt table test, however patients should always check with their ordering physician to verify whether they should or should not take they medications.
Location: Tilt table tests are performed at the hospital.