September 9, 2015
What is a Endoscopic Ultrasound (EUS)?
A procedure that combines an endoscope and high frequency sound waves to obtain high quality ultrasound images of the upper digestive tract in order to screen for diseases like hidden gallstones, and to evaluate possible tumors. EUS is a very sensitive test. It may be helpful in obtaining more information for a diagnosis when other tests are inconclusive. It is also very important in deciding what the best course of treatment should be (e.g.. when and if to start chemotherapy or surgery) in both precancerous and cancer diseases.
How do I prepare for my procedure?
Your doctor will want to know about your health status especially if you have any allergies, other significant health problems such as heart disease, lung disease, or diabetes mellitus.You will also be asked about allergies to iodine or shellfish as, under certain circumstances, iodine containing contrast material may be used. If there is a possibility of fine needle aspiration (FNA), which is a type of tissue sampling done during EUS, the doctor will want to check your blood for proper clotting. It is important to inform your doctor of any family history of bleeding problems or if you are taking medications that interfere with blood clotting (such as Coumadin, Xarelto) or platelet function (such as aspirin, Plavix, Advil, Aleve, or other NSAIDs). The wisest approach is to inform your doctor of ANY prescription or non-prescription medication you might be taking. Antibiotics are usually not required. EUS is performed with propofol sedation given by an anesthesia professional, so you will not be able to return to work or to drive until the following day. It also means that you will need someone to take you home, since EUS is usually an outpatient procedure. You will need to have an empty stomach, which means no food intake for 6 or more hours and no liquids for at least 2 hours. In case of a rectal EUS, you will probably need to take some enemas or laxatives. In either case, full instructions will be given to you.
How is the procedure performed?
Upon arrival at the endoscopy center, the nurse or the doctor will discuss the procedure and answer any questions. You will then be asked to sign consent forms indicating you were informed about the procedure, its alternatives, its risks and about sedation to be given. You will change into a hospital gown. An IV will be placed in a vein for giving fluid and medication needed. General Anesthesia is rarely used. You will then be taken into the procedure room and, after the administration of the sedation, the EUS will be carried out. Heart rhythm, blood pressure, pulse, and blood oxygen are monitored. Once sleepy, the special endoscope will be inserted by mouth for upper GI procedures ore rectally to examin parts of the colon. Due to the sedation, you will ordinarily have no significant awareness of the procedure going on, but wake up quickly and nearly completely right after it is finished. The physician observes the inside of your intestinal tract on a monitor and the ultrasound image on special equipment, and findings are recorded. The entire procedure generally takes 30 to 60 minutes depending on the complexity and whether fine needle aspiration (FNA) is performed. Sometimes, medications are injected into deep nerves to deaden them if pain is being caused, for example as part of pancreatic cancer treatment.
What can I expect after my procedure?
After the procedure, you will be sleepy for up to one hour and then be able to drink fluid and start to get up and dressed to go home. Once you are awake enough, the doctor will discuss with you the findings of the procedure. Tissue sample results if involved will be analyzed by the pathology lab and results reported to you in a couple of days.
What are the risks involved with the procedure?
P Like other endoscopy procedures, EUS is safe and well tolerated. No procedure is without risk, but complications with EUS are quite rare. Complication rate for EUS without the fine needle aspiration is about one in two thousand. This is similar to the complication rate of other endoscopy procedures. Sometimes, patients can develop reactions such as hives, rash, or nausea, to the medications used during EUS. A lump may appear in the area of the vein where the IV was placed. This usually resolves over time. Should it persist, you should contact your physician. The main complication of serious note is perforation (a tear) in the intestinal wall that commonly would require surgical repair. This is quite rare and precautions are taken to avoid it. Infection or bleeding would be very unusual. Extreme precautions are taken to clean scopes meticulously to avoid transmitting infection.
What are my alternatives to this procedure?
In patients with suspected cancer, biopsies are needed to confirm the diagnosis before any treatment can be started. CT scan or conventional ultrasound-guided biopsies are good methods for tumors close to the skin. However, EUS is safer and more accurate for “deep” tumors, such as those in pancreas or bile ducts. EUS can obtain biopsies by extracting a small number of cells with a very fine needle from across the digestive tract (esophagus, stomach, intestines and rectum) avoiding damage to overlying vital organs and blood vessels. Surgery for a diagnosis is an alternative to EUS but is much more invasive and requires general surgical procedures with general anesthesia.