The gallbladder is an important organ of the digestive system that stores bile. This is formed in the liver and released into the duodenum by the bile. Bile is primarily needed for the digestion of fat . Gallstones can form in the bile, which in rare cases can lead to serious illnesses.
Article overview
Where is the gallbladder located?
The gallbladder is located in the right upper abdomen. It sits below the liver in the gallbladder cavity.
The liver and gallbladder are connected by a connective tissue bridge. Below the gallbladder are the duodenum and the downward bend of the large intestine. Where the gallbladder is not attached to the liver directly or via the connective tissue, it is covered with peritoneum.
© Henrie / Fotolia
How is the gallbladder structured?
The gallbladder is 8 to 12 cm long and 4 to 5 centimetres wide. The wall thickness of the gallbladder is around 4 mm.
As a storage organ , the gallbladder holds 30 to 80 ml of bile. The anatomical structure of the gallbladder consists of the gallbladder floor, gallbladder body and gallbladder neck. The Heister valve located in the neck of the gallbladder and in the cystic duct prevents uncontrolled outflow of bile and only releases it when necessary.
The green-colored bile makes the gallbladder appear greenish.
What functions does the gallbladder perform?
The hollow organ, which resembles a pear in shape, serves to absorb and thicken the bile produced in the liver. This consists mainly of water, bile acids, phospholipids, cholesterol, bilirubin and other pigments. The inside of the gallbladder is lined with a mucous membrane that protects it from the digestive substances in the bile. The gallbladder wall also contains muscle tissue.
The gallbladder fluid enters the gallbladder from the liver via the common hepatic duct. From there, it later enters the duodenum through the exit of the gallbladder - the common bile duct.
In total, the liver releases between 0.5 and 1 liter of yellow bile per day. This liver bile turns into green bladder bile in the gallbladder. The color change occurs when the bile thickens in the gallbladder, whereby 50 to 60 ml of bladder bile is produced from up to one liter of liver bile.
The bile produced by the liver and released by the gallbladder plays an important role in the digestion of fat in the intestine. After a meal, the organ contracts and pushes the bile through the bile ducts into the duodenum. Bile is emptied from the gallbladder by contracting the gallbladder wall muscles. This process is triggered by hormone-active cells in the intestinal wall and acetylcholine activated by the vagus nerve.
Once in the duodenum, the bile begins its work: it dissolves the dietary fats into droplets, which are then broken down by enzymes.
Which diseases occur frequently?
Typical triggers for gallbladder diseases are gallstones and inflammation, whereby gallbladder inflammation is often caused by the presence of gallstones, and occasionally also by tumors or polyps in the gallbladder.
Gallstones
If the ratio between the bile components cholesterol and bile acid is out of balance, solidification occurs in the form of gallstones. The initially small gallstone can grow through further deposits - from the size of a grain of sand to a cherry. Most gallstones consist mainly of cholesterol.
The stones collected in the gallbladder do not cause any problems, at least not initially. Many people have no idea that they have gallstones and are spared gallstone problems for the rest of their lives. In Germany, around 15 % of all women and 7.5 % of all men have gallstones. Of these, 75% have no health problems as a result.
Health problems caused by gallstones occur when small stones get into the narrow bile ducts or a large stone rolls in front of the gallbladder outlet. Both block the outflow of bile. The pressure of the accumulated bile on the gallbladder wall causes pain in the right upper abdomen, which often increases to the point of almost unbearable colic.
Fat-heavy meals encourage the process, as the digestive system requires correspondingly large amounts of bile.
Removed gallstones © Jürgen Fälchle / Fotolia
Gallbladder inflammation
Gallbladder inflammation or cholecystitis almost always occurs as a result of gallstone complaints. The intense pressure exerted on the gallbladder wall by the accumulated bile causes the gallbladder to become inflamed.
The onset of upper abdominal pain, which is usually cramp-like or colicky, can even spread to the right shoulder. Other symptoms accompany gallbladder inflammation:
- Nausea
- vomiting
- fever
- chills
- faintness
- Brown colored urine
- jaundice
Gallbladder inflammation that is not caused by gallstones is known as "acalculous cholecystitis". It is triggered by infections, major abdominal surgery and accidents.
Inflammation of the bile ducts
The bile ducts can also become inflamed if gallstones that have gotten into them prevent the flow of bile. Tumors or infections are less common causes of bile duct inflammation.
Possible complications of gallbladder diseases
Gallbladder diseases are not simply unpleasant or annoying, but can lead to life-threatening complications. Repeated symptoms caused by gallstones in the gallbladder or bile ducts suggest surgical removal.
Through contractions, the gallbladder and bile ducts often manage to move a gallstone that is obstructing the outflow into a more favorable position, which alleviates the symptoms. However, if this is not successful, the constantly flowing bile may cause the gallbladder to burst due to excess pressure. The bile that enters the abdominal cavity as a result can lead to life-threatening peritonitis.
Chronic inflammation can also cause the gallbladder to shrink . The constant mechanical irritation of the gallbladder and bile ducts caused by gallstones also favors the development of carcinoma, i.e. a malignant tumor.
A backlog of bile can also affect the neighboring organs of the liver and pancreas.
Diagnosis of gallstones and gallbladder inflammation
When describing the symptoms, the doctor will include possible gallstones or gallbladder inflammation in his diagnosis. The following examination procedures will provide further information:
- Palpation
- sonography
- X-ray with contrast medium
- Blood test: in particular liver values and inflammation values
Removal of the gallbladder
In the case of gallbladder complaints requiring treatment, gallbladder removal is now standard medical practice, regardless of whether it is a case of gallbladder inflammation or "just" stones. As gallstones often develop congenitally, they would recur after removal. Similarly, gallbladder inflammation is almost always caused by gallstones, which means that gallbladder removal is recommended. In contrast to kidney stones, gallstones treated with shock wave therapy carry the risk that pieces of gallstone debris will remain in the tissue, making follow-up surgery necessary.
Two procedures are used for the surgical removal of the gallbladder, also known as cholecystectomy :
- conventional cholecystectomy
- laparoscopic cholecystectomy
In the conventional surgical method, which is rarely performed nowadays, the gallbladder is removed via an abdominal incision below the right costal arch.
The usual medical standard for gallbladder removal is now laparoscopy, also known as keyhole surgery or minimally invasive surgery. This involves just four tiny incisions, three of which are used to insert instruments and cameras into the abdominal cavity, while the surgeon removes the gallbladder and its contents through the fourth incision.
Patients then recover quickly and can usually leave the hospital after 2 to 4 days. The bile that continues to be produced by the liver is now passed directly into the duodenum.
Conclusion on the gallbladder
The gallbladder serves as a reservoir for the bile produced in the liver. Occasionally, this leads to the formation of gallstones. Gallbladder diseases are usually caused by such gallstones.
In many cases, the standard treatment for gallbladder diseases is minimally invasive removal of the gallbladder.