An abdominal hematoma is a collection of clotted blood within the abdominal cavity or the abdominal wall tissues. Depending on its location and the rate of bleeding, an abdominal hematoma can be fatal if not promptly treated. The severity depends on whether the bleeding is contained and stable or massive and expanding.
Defining Abdominal Hematoma
A hematoma is a localized pool of blood that has escaped from a blood vessel and clotted in an extravascular space. Abdominal hematomas are categorized by location: those within the abdominal wall and those deeper inside the abdominal cavity. The most common type of abdominal wall bleed is a rectus sheath hematoma, occurring in the muscle layers of the abdomen.
Hematomas inside the cavity, such as retroperitoneal, hepatic, or splenic hematomas, pose a greater risk. The abdominal wall space is confined, sometimes allowing surrounding tissue to tamponade, or naturally stop, the bleeding. In contrast, the abdominal cavity and retroperitoneal space can hold a large volume of blood before external signs become noticeable, allowing significant internal hemorrhage.
Physicians classify these bleeds as either stable or unstable, which dictates treatment urgency. A stable hematoma is a contained collection of blood where bleeding has stopped, and the patient’s vital signs remain normal. An unstable hematoma is actively bleeding or expanding rapidly, causing the patient’s condition to deteriorate and requiring immediate intervention.
Mechanisms of Fatal Risk
The life-threatening nature of an abdominal hematoma stems from two primary mechanisms: hypovolemic shock and pressure effects within the abdomen. Massive, ongoing internal hemorrhage is the most immediate danger. The rapid loss of blood volume outside the circulatory system causes hypovolemic shock, which depletes the body’s oxygen-carrying capacity. This leads to a swift drop in blood pressure, circulatory collapse, and insufficient oxygen delivery to vital organs.
The second danger arises from the physical volume of the expanding hematoma, which can lead to abdominal compartment syndrome (ACS). ACS is defined by a sustained intra-abdominal pressure greater than 20 mmHg accompanied by new organ dysfunction. This elevated pressure compresses the internal organs, impairing their function.
The high pressure impairs the return of blood to the heart by compressing large veins, leading to reduced cardiac output. The rising abdominal pressure also pushes the diaphragm upward, severely restricting lung expansion and compromising breathing. The kidneys are vulnerable, as the pressure decreases renal blood flow, causing acute kidney injury and a rapid drop in urine output. If this pressure is not relieved quickly, the resulting multi-organ failure can be fatal.
Recognizing the Critical Symptoms
Recognizing the signs of an unstable, potentially fatal hematoma is crucial. The onset of sudden and severe abdominal pain, often accompanied by noticeable distension or swelling, is a significant warning sign. Patients may present with a palpable mass in the abdomen that is firm and tender, and this mass may be actively expanding.
Signs of hypovolemic shock indicate life-threatening internal bleeding. Symptoms include a rapid heart rate (tachycardia) and low blood pressure (hypotension) as the body attempts to compensate for blood loss. The patient may also appear pale, clammy, and confused due to poor blood flow. Falling hemoglobin levels on blood tests confirm ongoing blood loss, signifying the need for immediate emergency care.
Emergency Management and Recovery
The emergency management of an abdominal hematoma is determined by the patient’s stability and the hematoma’s characteristics. For smaller, stable hematomas that are not actively bleeding, non-operative management is employed. This approach involves close observation in a hospital setting, strict bed rest, pain management, and monitoring of vital signs and serial blood counts.
In contrast, an unstable or rapidly expanding hematoma requires aggressive, immediate intervention. Initial steps focus on rapid fluid resuscitation with intravenous fluids and blood transfusions to stabilize blood pressure and replace lost blood volume. The definitive treatment aims to stop the source of the bleeding.
This may involve interventional radiology, where a catheter is threaded through blood vessels to the hemorrhage site to perform embolization, blocking the damaged vessel with coiling material. If embolization is unsuccessful, emergency surgery may be necessary to directly ligate, or tie off, the bleeding vessel and evacuate the large clot. A positive outcome depends on the speed of diagnosis and the swiftness of the intervention to control the hemorrhage and reverse the effects of shock or abdominal compartment syndrome.