The abdomen can be injured in many ways. The abdomen alone may be injured or injuries elsewhere in the body may also occur. Injuries can be relatively mild or very severe.
Doctors often classify abdomen injuries by the type of structure that is damaged and how the injury occurred. The types of structures include the
Abdominal injuries may also be classified by whether the injury is
Blunt trauma may involve a direct blow (for example, a kick), impact with an object (for example, a fall onto bicycle handlebars), or a sudden decrease in speed (for example, a fall from a height or a motor vehicle crash). The spleen and liver are the two most commonly injured organs. Hollow organs are less likely to be injured.
Penetrating injuries occur when an object breaks the skin (for example, as a result of a gunshot or a stabbing). Some penetrating injuries involve only the fat and muscles under the skin. These penetrating injuries are much less concerning than those that enter the abdominal cavity. Gunshots that enter the abdominal cavity almost always cause significant damage. However, stab wounds that enter the abdominal cavity do not always damage organs or blood vessels. Sometimes, a penetrating injury involves both the chest and the upper part of the abdomen. For example a downward stab wound to the lower chest may go through the diaphragm into the stomach, spleen, or liver.
Blunt or penetrating injuries may cut or rupture abdominal organs and/or blood vessels. Blunt injury may cause blood to collect inside the structure of a solid organ (for example, the liver) or in the wall of a hollow organ (such as the small intestine). Such collections of blood are called hematomas. Uncontained bleeding into the abdominal cavity, in the space surrounding the organs, is called hemoperitoneum.
Cuts and tears begin bleeding immediately. Bleeding may be minimal and cause few problems. More serious injuries may cause massive bleeding with shock and sometimes death. Bleeding from abdominal injury is mostly internal (within the abdominal cavity). When there is a penetrating injury, a small amount of external bleeding may occur through the wound.
When a hollow organ is injured, the contents of the organ (for example, stomach acid, stool, or urine) may enter the abdominal cavity and cause irritation and inflammation (peritonitis).
In addition to the immediate damage, abdominal injuries may also cause problems later on. These delayed problems include
The body is usually able to reabsorb collections of blood (hematomas), although it may take several days to weeks. However, a hematoma sometimes ruptures rather than being resorbed. Rupture can occur within the first few days after injury, but sometimes rupture occurs later, occasionally even months later.
Rupture of a hematoma of the wall of the intestine can allow intestinal contents to leak into the abdomen and cause peritonitis. Intestinal wall hematomas sometimes form a scar when they heal. This scarring can cause narrowing of the intestine at that spot that leads to intestinal obstruction, typically years later.
Abscess within the abdominal cavity may occur if injury to a hollow organ is not detected. Abscesses may also form after surgery to repair a serious abdominal injury.
Sometimes scar tissue forms after an injury heals or after surgery on the abdomen. That scar tissue forms fibrous bands (adhesions) between loops of intestine. Usually, these adhesions cause no symptoms, but sometimes another loop of intestine gets twisted under an adhesion. This twisting can block the intestine (intestinal obstruction) and cause abdominal pain and vomiting. Sometimes surgery is required to remove the adhesion and unblock the intestine.
Just as a sprained ankle or broken arm swells, abdominal organs swell after an injury (particularly if there was surgery). Although there is usually enough room in the abdomen for such swelling, unchecked swelling ultimately increases pressure in the abdomen. The increased pressure squeezes the organs and restricts their blood supply, which causes pain and then organ damage. Such pressure-related damage is called abdominal compartment syndrome. It is much like compartment syndrome that can occur in the lower leg when injured by, for example, a fracture. Increased abdominal pressure may eventually also increase pressure in other body tissues, such as the lungs, kidneys, heart, blood vessels, and central nervous system. Abdominal compartment syndrome tends to develop in people with severe injuries or injuries that require surgery. Abdominal compartment syndrome is extremely serious and increases the risk of death.
People usually have abdominal pain or tenderness. However, pain can be mild, and the person may not notice or complain about it because of other more painful injuries (such as fractures) or because the person is not fully conscious (for example, because of a head injury, substance abuse, or shock). Pain from a spleen injury sometimes radiates to the left shoulder. Pain from a small intestinal tear is minimal at first but worsens steadily. People with a kidney injury or bladder injury may have blood in the urine.
People who have lost a large amount of blood may have
Blunt trauma may cause bruising (for example, people who were wearing a seat belt during a motor vehicle crash may have a bruise across the chest or the lower abdomen, called the seat belt sign). Not all people have bruising, and the presence of a bruise does not necessarily reflect the severity of the abdominal injury. In people with severe bleeding, the abdomen may be swollen because of the excess blood.
In some people, abdominal injury is obviously severe (such as many gunshot wounds). Doctors take such people directly to the operating room for exploratory surgery and do not do tests to identify the specific injuries. However, most people with an abdominal injury require testing. The testing identifies the specific injury and, combined with the findings on the physical examination, helps doctors decide which people require an operation.
The main testing options include ultrasonography and computed tomography (CT). Ultrasonography can be done quickly at the person's bedside, and is useful for finding severe bleeding. CT takes a little longer and requires moving the person to the scanner but gives more precise images. CT also can detect other injuries such as fractures to the spine or pelvis. Depending on the type of injury, x-rays of the chest or pelvis may also be needed.
Doctors also do urinalysis to detect blood in the urine, which indicates damage to some part of the urinary system. Usually a complete blood count is done so doctors have initial information to compare should the person need further treatment.
People are given intravenous fluid as needed to replace blood loss. People who have lost a significant amount of blood are given blood transfusions.
Surgery may be needed to
Although many injuries to solid organs, such as the liver and spleen, heal on their own, people with abdominal organ injury detected by CT or ultrasonography are hospitalized and examined every few hours to ensure that bleeding stops and symptoms do not worsen. Sometimes CT or ultrasonography is repeated.