There are times when we feel increased pressure within the abdomen with no other symptoms. It may not be painful but does cause some degree of discomfort and uneasiness. This fullness sensation may or may not be accompanied by an abnormal enlargement of the abdomen. A fullness or bursting pressure feeling in the abdomen can occur for various reasons, some of which are due to diseases. However, there are times when this fullness cannot be explained. It may be momentary, lasting for few hours or days, and then resolves with no further problem.
Why does the abdomen feel like bursting?
Pressure within the abdomen is known as the intra-abdominal pressure. When it is within normal limits, we do not feel any discomfort or unusual sensation. Unlike the chest, the abdominal cavity does not have bones surrounding it. This means that the abdominal wall is not as rigid. It is made up of skin, muscles, fat and connective tissue which allows it can stretch or shrink to some extent.
However, if the intra-abdominal pressure rises with or without any visible or measurable enlargement of the abdomen then we may feel a sensation of fullness. Depending on the increase of the pressure within, it can compress abdominal organs and even stretch the abdominal wall to uncomfortable or painful limits. As discussed below, it is important to differentiate a fullness sensation from any actual distension of the abdomen.
Read more on abdominal tightness.
Bloating vs Distension
The term abdominal fullness may either refer to a sensation of fullness or pressure within the abdomen and/or it can also refer to enlargement of the abdomen. This pressure sensation is also known as bloating while enlargement or an increase in the abdominal girth is also termed as distension. The sensation of bloating may occur with or without distension whereas distension is almost always accompanied by a bloating sensation.
However, the term bloating may sometimes be used to refer to abdominal distension even though the abdomen can enlarge signfiicantly without any discomfort, fullness or pressure being felt by a person. Distension usually indicates that fluid, a mass or sometimes gas has accumulated within the abdomen. Bloating may not necessarily be due to any space-occuping lesion and can just be a sensation elicited by certain diseases of the abdominal organs.
Causes of Abdominal Fullness
Some of the causes of abdominal fullness have been discussed below but may not include all the possible conditions responsible for bloating or abdominal distension. It is therefore important to consult with a medical professional as further diagnostic investigations may be required to identify the exact cause. Furthermore the presence of other symptoms like abdominal pain, nausea, vomiting and change in bowel habit may also be helpful in identifying he exact cause of abdominal fullness.
One of the most common causes for a feeling of fullness in the abdomen is due to trapped gas. This may occur in the upper gut when gas cannot be released as a belch or in the lower gut such as within the colon when gas cannot be expelled as flatus. Trapped gas is more likely to occur when there is excessive quantities of gas in the gut or when there is a narrowing or sudden bend in the gut, as may occur with splenic flexure syndrome.
Most of the time the gas in the upper gut is due to air swallowing (aerophagia). Gas in the intestines may also be air that was swallowed but also includes gas produced by fermentation, due to the action of colonic bacteria and some gas passed out of the bloodstream into the gut. Contrary to popula belief, gas in the gut does not cause abdominal distension but just a feeling of fullness within the abdomen.
Overeating or eating very fast can cause the excessive stretching of the upper gut, particularly of the stomach. This stretching of the stomach may cause the sensation of fullness. It may also occur with drinking carbonated beverages such as colas, fizzy drinks and beer. Foods that are high in fiber may have a similar effect as it absorbs water in the gut to bulk up and occupy more space.
Stomach and Intestines
Several conditions involving the abdominal portion of the digestive tract can cause a fullness sensation in the abdomen. From the stomach to the colon, any abnormal stretching, narrowing or growth may cause a sensation abdominal fullness. However, some of the more common causes include:
- Peptic ulcers
- Intestinal obstruction
Constipation is a common problem and may also cause fullness in the abdomen. This may be worsened when complications of constipation, like fecal impaction, arises. Some conditions of the bowels, like irritable bowel syndrome (IBS) may cause bloating for no clearly identifiable reason and this is known as functional bloating.
Read more on functional abdominal bloating.
Gallbladder and Pancreas
Both gallbladder and pancreatic conditions can also cause a fullness sensation in the upper abdomen specifically. Gallstones, gallbladder inflammation (cholecystitis) and acute pancreatitis are some of the more likely conditions to cause a feeling of abdominal fullness. In addition there may be other symptoms like upper abdominal pain, nausea, vomiting (sometimes) and change in bowel habit. Symptoms typically start a short while after eating.
Fluid accumulation in the abdomen is known as ascites and one of the leading causes is liver disease. This may include conditions such as viral hepatitis, alcoholic hepatitis, cirrhosis and liver cancer. These diseases may cause pressure to build up in the liver veins and affect the fluid balance in the body thereby leading fluid accumulation in the abdominal cavity. In addition, enlargement of the liver (hepatomegaly) with/without spleen enlargement (splenomegaly) can also cause a feeling of abdominal fullness particularly in the upper abdomen.
Ascites (fluid accumulation in the abdomen) is one of the features of an imbalance in the fluid and electrolyte levels in the body. This can occur with kidney diseases when the kidneys are unable to pass out excess water from the body. It can arise acute or chronic kidney failure, kidney infections (pyelonephritis), glomerulonephritis and other kidney diseases. Liver conditions can also impact on kidney functioning.
Fluid from the blood vessels can leak out into the abdominal cavity when the heart is unable to circulate blood efficiently. This may occur with a host of heart conditions including heart failure, cardiomyopathy and inflammation of the heart (carditis). It may also be impact by both kidney and liver disease when there is retention of fluid and the fluid load returning to the heart is higher than normal.
Peritonitis is inflammation of the membrane that covers the abdominal organs and inner abdominal wall. This membrane is known as the peritoneum. It can arise when any of the abdominal organs burst and release chemicals into the peritoneal space. Bacteria than enter this space can also infect the peritoneum. Large amounts of fluid can accumulate in this space, including blood. This may cause a bloated sensation and abdominal distension.