Overview of Canine Hemoabdomen & Hemoperitoneum: Abdominal Bleeding in Dogs
Hemoperitoneum (also commonly called hemoabdomen) is defined as blood within the peritoneal (abdominal) cavity. Most veterinarians use the term hemoabdomen in dogs. The blood accumulates in the space between the inner lining of the abdominal wall and the internal abdominal organs. Abdominal bleeding can occur in dogs that suffer from traumatic injuries, tumors, and hematomas.
Causes of Abdominal Bleeding in Dogs
- Traumatic injuries – these are most common
- Intra-abdominal tumors or tumors within the abdomen – these can rupture, slowly bleed, or invade into a blood vessel causing blood to enter the abdominal cavity
- Hematomas – these are organized, local collections of blood that can rupture and bleed
- Coagulopathies – these are clotting disorders that can cause bleeding within the abdomen as well as in other sites
Depending on the degree of blood loss, and how rapidly the blood is lost, a hemoperitoneum may be an emergency situation.
What to Watch For
- Abdominal distension
- Subcutaneous (under the skin) bruising
- Increased respiratory effort
- Pale mucus membranes (the best place to check is the gums or inner lining of the lips)
Other signs that might indicate a more chronic (longer term or gradual) blood loss include anorexia, lethargy, intermittent weakness, and weight loss.
Diagnosis of Hemoabdomen & Hemoperitoneum in Dogs
A thorough history and physical exam are critical for a prompt, and accurate diagnosis. Your veterinarian may also recommend:
- Abdominal radiographs (x-rays)
- Abdominocentesis (inserting a needle and syringe into the abdominal cavity) to obtain a sample for diagnostic evaluation
- Fluid analysis of the retrieved sample is required for definitive evaluation
- Complete blood count
Depending on your pet’s condition and initial test results, additional tests that may be required. These may include:
- Biochemical profile
- Coagulation panel
- Abdominal ultrasound
- Computed tomography (CT) or magnetic resonance imaging (MRI)
Treatment of Hemoabdomen & Hemoperitoneum in Dogs
The general approach to treatment varies on the clinical condition of the patient and the cause of the hemoperitoneum. Therapy generally includes:
- Intravenous fluid therapy
- Blood transfusions
- Belly wrap
- Oxygen therapy
- Analgesic therapy (pain medication)
- Vitamin K administration
- Emergency exploratory surgery
A hemoperitoneum may be an emergency situation. Veterinary care should be given as soon as possible. Keep your pet calm and comfortable. Minimize stress until you can get to a veterinary hospital. Keep your pet warm. If a traumatic injury is suspected, be careful moving your pet, as fractures may be present.
In-depth Information on Canine Hemoabdomen
A hemoperitoneum is a potential life-threatening situation. The peritoneal or abdominal cavity is a potentially large space that could contain a significant amount of blood. If a large amount of blood is lost into this space, the abdominal wall musculature is stretched and abdominal distension will be noted. Abdominal distension also may cause discomfort and pain, leading to increased agitation and stress. The rapid expansion of the abdomen may also cause pressure on the diaphragm, and thus, a decreased ability to breath comfortably.
Rapid blood loss into the abdomen will also lead to a decrease in blood pressure and tissue perfusion. This may lead to shock. As continued blood is lost, the decrease in circulating red blood cells may lead to acute (sudden) anemia. Pale mucus membranes are commonly observed. If veterinary care is not immediately available, rapid blood loss may lead to death. A slower blood loss is more common and will allow for more time to seek veterinary care.
Chronic (long standing) or intermittent blood loss generally occurs more slowly, and more subtle clinical signs might be present. If the blood loss is slow, the body can reabsorb (auto transfuse) the free blood in the abdomen. Thus, dogs may only have a small amount of blood present in the abdominal cavity. These dogs may not present as an emergency, but they still may have a serious underling disease process. Making the diagnosis of a hemoperitoneum is critical in establishing an underling cause.
If the dog has normal clotting parameters the bleeding into the abdomen will, many times, stop on it’s own. Blood clots form that stop the bleeding. Sometimes, an animal will collapse due to the acute blood loss, and then slowly recover due to clot formation, and the body’s own compensatory mechanisms. These animals will appear pale and weak initially, but with time, slowly become stronger and their mucus membranes will again become pink. Owners may describe intermitted episodes of weakness followed by spontaneous recovery. Blood clots can, however, be dislodged especially with increased movement or manipulations. If blood clots are dislodged, the bleeding may start again. In many cases of hemoperitoneum due to abdominal trauma, the bleeding will stop on its own.
Causes of Bleeding
There are several main causes of a hemoperitoneum. Probably the most common of hemoperitoneum in dogs cause is trauma. A lacerated blood vessel within the abdomen or internal organ trauma may lead to rapid or slow bleeding depending on the amount of organ or tissue damage. Outdoor dogs are at significantly greater risk then indoor animals. Younger dogs are more likely to be injured as well.
In young dogs with a hemoperitoneum and no history of trauma, a coagulopathy (bleeding disorder) should be suspected. In these animals, the bleeding usually does not stop on its own, unless vitamin K and other appropriate therapy is administered.
In older dogs with a hemoperitoneum and no history of trauma, a bleeding tumor within the abdomen is often the cause. Bleeding tumors may cause a rapid blood loss or be chronic, having intermittent smaller bleeding events.
Specific causes of hemoperitoneum include:
- Trauma. The most common traumatic injury causing a hemoperitoneum occurs when a car has hit an animal. Severe abdominal trauma may cause a rapid death if the bleeding is significant. Most of the time, bleeding occurs more slowly and there is time to seek emergency care. The spleen and liver are common internal organs that may be traumatized, and cause a hemoperitoneum. Less commonly, the bladder or kidneys may bleed into the abdomen, but this is generally also associated with an uroabdomen (urine within the peritoneal cavity). The bleeding may be mild or severe, but most of the time will stop without intervention. Other cause of trauma include gun and knife wounds.
- Tumors. Tumors in the abdomen may erode a blood vessel or simply rupture causing an acute bleed. Tumors located on the peritoneal surface of the abdomen, or more commonly associated with abdominal organs, may cause bleeding into the abdomen. The most common tumor to cause intra-abdominal bleeding is a hemangiosarcoma (a tumor of blood vessels). These tumors are aggressive and malignant. They are commonly found on the spleen or liver. Golden retrievers and German shepherd dogs are two breeds at increased risk of getting this tumor. A hemangioma is the benign form, but it is not as commonly seen. Hemangiosarcoma is a very common tumor in dogs.
- Hematomas. Hematomas are formed by broken blood vessels that cause blood to accumulate in a tissue, organ or space. They are a common cause of hemoperitoneum, and usually are associated with the spleen. They may be caused by previous trauma, or more commonly nodular regeneration (excessive production of splenic tissue). Hematomas may be quite large and are indistinguishable from hemangiosarcomas at surgery.
- Coagulopathies. Rodenticide poisoning with products containing anticoagulants is a very common cause of bleeding disorders in animals. The bleeding may be exclusively within the abdomen, or may involve other sites (e.g. under the skin). Products containing the following active ingredients may cause a hemoperitoneum: warfarin, fumarin, chlorophacinone, diphacinone, pindone, bromadiolone, or brodaficoum.
The order of diagnostic tests depends on the clinical condition of the pet. In an emergency situation, the pet would be stabilized prior to significant diagnostic procedures. A rapid but thorough veterinary evaluation is critical to prioritizing appropriate diagnostic procedures.
- Abdominal radiographs are a good test to see if fluid is present in the abdominal cavity. Although they are a good initial diagnostic, they cannot discern the type of the fluid type. Abdominal radiographs also may identify mass lesions (tumors or hematomas). Unfortunately, a large volume of fluid in the abdomen will often make the radiographic visualization of masses more difficult.
- Abdominocentesis – A small sample of fluid is withdrawn from the abdominal cavity and the fluid submitted for microscopic analysis. The bloody fluid withdrawn should not clot, since blood in the peritoneal space rapidly becomes defibrinated (loses it’s ability to form a clot). When a hemorrhagic (bloody) fluid is obtained that does clot, it usually means that a blood vessel was inadvertently aspirated. The fluid analysis will show mainly red blood cells with some white blood cells, in quantities similar to peripheral blood. The hematocrit (red blood cell count) should be similar to that of the peripheral blood.
- The complete blood count – The CBC is an important test since it evaluates the red and white blood cell lines. When a hemoperitoneum is suspected, a hematocrit is used to evaluate the degree of blood loss (anemia). The CBC also provides information on if the bleeding was acute or chronic. Red blood cell morphology (shape) changes may suggest that hemangiosarcoma or other malignancy is present.
- The biochemical profile is a useful test to evaluate if any other organ systems are affected. Animals with traumatic injuries (and sometimes, cancer) will often have elevated liver enzymes. Kidney function is also evaluated.
- Full clotting tests are especially important in young animals with no trauma history. If trauma and intra-abdominal (within the abdominal cavity) tumors are ruled out, or if the bleeding is not stopping, a clotting panel is indicated.
- An abdominal ultrasound is used to determine if there is an abdominal tumor or hematoma present. Unlike radiographs, fluid in the abdomen does not inhibit the visualization of masses. An ultrasound- guided biopsy may be considered if a mass is found; however, many times the biopsy is non-diagnostic since some masses are mostly blood. Care must be taken when these masses are biopsied, as they do tend to bleed. Animals with splenic masses have the highest incidence of these potential problems.
- CT or MRI – Rarely a mass may be too small to be visualized on ultrasound. A CT or MRI available at specialty hospitals may identify these difficult to visualize masses.
One or more of the diagnostic tests described above may be recommended by your veterinarian. In the meantime, treatment of the symptoms might be needed, especially if the problem is severe. The following nonspecific (symptomatic) treatments may be applicable to some, but not all pets with hemoperitoneum. These treatments may reduce severity of symptoms or provide relief for your pet. However, nonspecific therapy is not a substitute for treatment of the underlying disease responsible for your pet’s condition.
If possible immediate veterinary care should be sought. A hemoperitoneum may be a life threatening condition requiring immediate intervention.
- Intravenous fluids are given if there is significant or rapid blood loss. Intravenous fluids maintain blood pressure and improve tissue perfusion. With trauma or bleeding abdominal masses, animals are commonly in shock, and may have multiple organ systems affected. Fluid therapy is critical in these patients, and animals often respond to treatment dramatically.
- Blood transfusions may also be required if there is a significant amount of blood loss causing anemia. Blood loss may be only within the abdomen, or be present elsewhere in the body.
- A belly wrap is a pressure bandage placed around an animal’s abdomen. It causes an increased intra-abdominal pressure that will sometimes slow or stop an abdominal bleed.
- Oxygen therapy may be needed in animals that have lost a large volume of blood. It is especially useful early in treatment, while initial fluids or blood products are being administered. Oxygen is administered via oxygen cage, mask or nasal oxygen canula.
- Analgesic medication – Keeping the patient still and calm is very important. If an animal is painful, they will have increased stress and be more likely to re-injure themselves. Bleeding that has previously stopped may start again. Treatment with narcotics or other pain medications helps keep animals more comfortable, and potentially more stable.
- Vitamin K is sometimes given if anticoagulant intoxication is suspected, even prior to getting test results back. The treatment has few side effects and rapid therapy improves prognosis.
- Exploratory surgery – If there is an abdominal mass, an exploratory may be the only way to obtain a diagnosis and treat the condition. If the clotting panel is normal, and abdominal bleeding is continuing, an exploratory might be recommended to stop the bleeding surgically and to discover the cause of the problem.