EUS allows your doctor to examine your stomach lining as well as the walls of your upper and lower gastrointestinal tract. The upper tract is the esophagus, stomach and duodenum; the lower tract includes your colon and rectum. EUS is also used to study internal organs that lie next to the gastrointestinal tract, such as the gall bladder and pancreas.
EUS provides your doctor with more information than other imaging tests by providing more detailed pictures of your digestive tract. Your doctor can use EUS to diagnose the cause of conditions such as abdominal pain or abnormal weight loss. Or, if your doctor has ruled out certain conditions, EUS can confirm your diagnosis and give you a clean bill of health.
EUS helps your doctor determine the extent of certain cancers of the digestive and respiratory systems. EUS allows your doctor to accurately assess the cancer’s depth and whether it has spread to adjacent lymph glands. In some patients, EUS can be used to obtain biopsies to help your doctor determine the proper treatment.
For EUS of the upper gastrointestinal tract, you should have nothing to eat or drink after midnight the night before your exam. For EUS of the rectum or colon, your doctor will instruct you to either consume a large volume of a special cleansing solution or to follow a clear liquid diet combined with laxatives or enemas prior to the examination. The procedure might have to be rescheduled if you don’t follow your doctor’s instructions carefully.
You can take most medications as usual until the day of the EUS examination. Tell your doctor about all medications that you’re taking and about any allergies you have to medication. Anticoagulant medications (blood thinners such as Coumadin or heparin) might need to be adjusted before EUS. Insulin also needs to be adjusted on the day of EUS. Check with your doctor in advance regarding these prescriptions. In general, you can safely take aspirin and nonsteroidal anti-inflammatories (Ibuprofen, naproxen, etc.) before an EUS examination. But it’s always best to discuss their use with your doctor. Check with your doctor about which medications you should take the morning of the EUS examination, and take essential medication with only a small cup of water.
You should inform your doctor prior to your test. Patients with latex allergies often require special equipment and might not be able to have an EUS examination.
Antibiotics aren’t generally required before or after EUS examinations. But tell your doctor if you take antibiotics before dental procedures. If your doctor feels you need antibiotics, antibiotics might be ordered during the EUS examination or after the procedure to help prevent an infection. Your doctor might prescribe antibiotics if you’re having specialized EUS procedures, such as to drain a fluid collection or a cyst using EUS guidance. Again, tell your doctor about any allergies to medications.
If you received sedatives, you won’t be allowed to drive after the procedure, even if you don’t feel tired. You should arrange for a ride home. You should also plan to have someone stay with you at home after the examination, because the sedatives could affect your judgment and reflexes for the rest of the day.
Practices vary among doctors, but for an EUS examination of the upper gastrointestinal tract, your endoscopist might spray your throat with a local anesthetic before the test begins. Most often you will receive sedatives intravenously to help you relax. You will most likely begin by lying on your left side. After you receive sedatives, your endoscopist will pass the ultrasound endoscope through your mouth, esophagus and stomach into the duodenum. The instrument does not interfere with your ability to breathe. The actual examination generally takes between 15 to 45 minutes. Most patients consider it only slightly uncomfortable, and many fall asleep during it. An EUS examination of the lower gastrointestinal tract can often be performed safely and comfortably without medications, but you’ll receive a sedative if the examination will be prolonged or if the doctor will examine a significant distance into the colon. You will start by lying on your left side with your back toward the doctor. Most EUS examinations of the rectum last from 10 to 30 minutes.
If you received sedatives, you will be monitored in the recovery area until most of the medications’ effects have worn off. If you had an upper EUS, your throat might be a little sore. You might feel bloated because of the air and water that were introduced during the examination. You’ll be able to eat after you leave the procedure area, unless you’re instructed otherwise. Your doctor generally can inform you of the results of the procedure that day, but the results of some tests will take several days.
Although complications can occur, they are rare when doctors with specialized training and experience, perform the EUS examination. Bleeding might occur at a biopsy site, but it’s usually minimal and rarely requires follow-up. You might have a slight sore throat for a day or so. Nonprescription anesthetic-type throat lozenges help soothe a sore throat.
Other potential, but uncommon, risks of EUS include a reaction to the sedatives used; aspiration of stomach contents into your lungs; infection; and complications from heart or lung diseases. One major, but very uncommon, complication of EUS is perforation. This is a tear through the lining of the intestine that might require surgery to repair.
The possibility of complications increases slightly if a deep needle biopsy is performed during the EUS examination. These risks must be balanced against the potential benefits of the procedure and the risks of alternative approaches to the condition.