ERCP Test

What is ERCP?

An ERCP, short for endoscopic retrograde cholangiopancreatography, is a non-invasive procedure that allows doctors to treat problems in the liver, gallbladder, bile ducts, pancreas and pancreatic duct. In children, they’re most commonly performed to remove a gallstone. "Endoscopic" refers to the user of the endoscope, "retrograde" refers to going against the direction of the flow of bile, and "cholangiopancreatography" refers to making images of the bile ducts and pancreatic duct.

The procedure combines two components: an endoscopy and fluoroscopic x-rays:

An endoscopy is a procedure that lets the doctor look at the upper parts of your child’s digestive system, including the esophagus, stomach, liver, bile ducts, pancreas, pancreatic duct and gall bladder.

During an endoscopy, while your child is under general anesthesia, the doctor guides an endoscope — a long, thin, flexible tube equipped with LED lights and a tiny video camera that transmits to several monitors in the room — into your child’s mouth and down into his upper digestive system.

Even though the endoscope is extremely narrow,  it is divided into two “channels.” The doctor can use the channels to:

  • transfer air into the GI tract, to make sure there’s enough room for what he or she needs to do
  • deliver medicine such as steroids straight into your child’s GI tract
  • slide tools through that will allow him or her to remove an obstruction or work within these tiny areas

Some areas of the body (such as the bile ducts) are so small that in order to see into them, the doctor needs to use the endoscope to inject them with a special contrast dye. This dye is visible in fluoroscopic x-rays, which show any abnormal narrowing or blockages in the duct. 

When are ERCPs performed?

Around 75 percent of patients have already been brought to the hospital (often because of severe pain or jaundice) when the doctor determines that they need an ERCP. Their symptoms may be caused by:

  • a gallbladder stone that is blocking bile (a vital fluid that helps the body break down and absorb nutrients) from flowing freely through the bile ducts. Bile ducts are tiny—about the size of a juice box straw—so it’s not uncommon for a gallbladder stone to get stuck in one.
  • being born with a duct that is too narrow, or other abnormality
  • pancreatitis (inflammation of the pancreas)

An ERCP may also be performed to investigate problems of the Sphincter of Oddi — a muscle that controls the opening and closing of the bile ducts. 

Since the gastrointestinal tract doesn’t have pain sensors, your child will not feel any pain; and our staff will be paying very close attention to make sure that he is sleeping comfortably.

What should I do to prepare my child for an ERCP?

Your child must have an empty stomach for an ERCP. After midnight the night before your child’s procedure, do not give them any:

  • solid food
  • milk
  • milk products
  • formula
  • juices with pulp, such as orange juice, pineapple juice or grapefruit juice

Your child can have clear liquids (including water, breast milk, apple juice, cranberry juice, Pedialyte® and Gastorade®) up until the times below:

  • if younger than six months — two hours before the test time
  • if older than six months — three hours before test time

What will happen during the procedure?

First, your child will be given medicine intravenously (through an IV) to help them relax or fall asleep. The doctor will spray a numbing medicine in his mouth to make the test more comfortable.

They will be attached to a heart monitor by wires connected to three stickers on their chest and also have a small lighted sticker on one of their fingers or toes that is connected to an oxygen monitor. 

The doctor will guide the endoscope down your child’s esophagus, into the stomach and into the small intestine to the ampulla of Vater, which is the opening of the common bile duct and the pancreatic duct. The common bile duct branches off into many smaller ducts. The doctor will inject a small amount of special contrasting dye into your child’s bile ducts, pancreas or pancreatic duct. This dye shows up as a blue area on the monitors, which allows the doctor to see stones or other areas of blockage that need to be removed.

Removing a stone

If the doctor sees one or more stones, they will remove them. In order to do this, they may first make a tiny cut in a nearby muscle in order to increase the width by a few millimeters. They will then insert tiny tools (that may look like a balloon or a basket) through the endoscope and use them to “sweep” the duct, pulling out any stones or other debris that may have collected there. Sometimes a stone may be too large to be swept out, so the doctor will break it up, often with a laser or with chemicals.

Dilating and stenting a duct

Whether there is a gallstone or not, the doctor might also see that a duct is too narrow for bile to pass through (stricture). Strictures may be caused by an inflammatory condition, or they may be present at birth. 

To treat a stricture, the doctor will pass a tiny balloon through the endoscope into the duct and then inflate the balloon under high pressure. When the balloon inflates, it causes a slight tear in the scar tissue that has built up in the duct and caused it to narrow. Once the balloon has created space in the duct, the doctor will insert a small plastic stent (tube) to keep it open, allowing the tear to  heal around this new, wider opening. 

For most children, the stent will stay in place for one to three months, and then the child will return to the hospital to have a procedure to remove the stent. Sometimes the doctor might find that the duct didn’t leave enough room when it healed and insert a new stent to keep it open. 

Treating pancreatitis

If a child has recurring pancreatitis (inflammation of the pancreas), scarring can build up in the pancreatic duct that can lead to strictures. Since these strictures can make the pancreatitis worse, the doctor will dilate and stent them.

Treating side effects of chemotherapy

Some chemotherapy treatments for cancer can cause the pancreatic duct to tear and bile can leak into a child’s intestine, making them very sick. The doctor can put a stent across the leak, allowing the duct to heal solidly around it.

How long does the procedure last?

An ERCP often takes about two hours from start to finish. That includes a lot of set-up time. The actual procedure can be as short as half an hour or as long as two to three hours, depending on the situation. In general, the larger the child’s body, the less time it takes.

Since manipulating a tissue of the body may cause it to swell, pancreatitis (inflammation/swelling of the pancreas) is a complication in 5 to 10 percent of ERCP. Sometimes this causes pain and vomiting. If this reaction is to occur, it usually develops within the first few hours after the procedure, and it’s common for children to stay at the hospital overnight for monitoring, just as a precaution. When pancreatitis does occur following an ERCP, it’s usually mild and short-lived.

Depending on the situation, most children are able to drink about two hours after the procedure or even in the recovery area, if they feel up to it. They can usually eat something an hour or two after the procedure.

Our approach to ERCP at Boston Children’s Hospital

Here at Boston Children’s, ERCPs are performed by the experienced clinicians of our Gastroenterology Procedure Unit (GPU) — a full-service unit providing an array of diagnostic and therapeutic endoscopy procedures in a safe, comfortable environment. Offering more than the typical gastroenterology (GI) endoscopy center, our specialists provide world-renowned care to children with gastrointestinal, pancreatic and hepatobiliary disorders. Our team attending physicians, nurses and endoscopy technicians who support the day-to-day practice of the unit. We also assist in the care of children with life-threatening cases in other areas of the hospital, such as the intensive care and surgical units, using our portable equipment. All nurses and physicians are certified in pediatric advanced life support (PALS).