Overview of Hemothorax: Bleeding in the Chest in Dogs
Hemothorax is defined as blood within the chest cavity. The most common cause of hemothorax in dogs is chest trauma, although tumors within the thorax (chest cavity) can also result in a hemothorax if they rupture, slowly bleed or invade into a blood vessel causing blood to accumulate in the thorax. Coagulopathies (clotting disorders) may also cause an animal to bleed within the chest cavity. A hemothorax is usually an emergency situation requiring rapid diagnosis.
What to Watch For
Your dog may take short, shallow, rapid breaths. Look for any observable subcutaneous (under the skin) bruising or evidence of external trauma.
Diagnosis of Hemothorax in Dogs
A thorough history and complete physical exam, emphasizing lung auscultation (listening with a stethoscope), is essential for prompt and accurate diagnosis. Your veterinarian may also recommend:
The above tests are generally the minimum required diagnostic tests needed to obtain a diagnosis. Depending on the animal’s condition, and initial test results, additional tests that may be required include:
Treatment of Hemothorax in Dogs
General approach to treatment varies depending on the clinical condition of the patient.
A hemothorax is generally an emergency situation. Veterinary care should be given as soon as possible. Keep your pet calm and comfortable and minimize stress. Keep your pet warm, and if a traumatic injury is suspected, be careful moving your pet, as fractures may be present.
In-depth Information on Hemothorax
A hemothorax is a potentially life threatening situation. In a normal animal the space between the lungs and the inner chest wall is called the pleural space. This space is more of a potential space, since a vacuum is present and the lungs are always in close contact with the pleural (inner lining) surface of the chest. Thus, as the chest or diaphragm expand, the lungs expand passively as well. If the pleural space becomes filled with blood, there is less room for the lungs to expand and fill with air. Breathing becomes more labored, and less oxygenated blood is distributed to the body. As the volume of blood increases, the ability to breath decreases and rapid intervention is needed.
Rapid blood loss into the chest can also lead to a decrease in blood pressure and tissue perfusion. This may lead to shock. As continued blood is lost, a decrease in circulating red blood cells may lead to acute (sudden) anemia. 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 the free blood in the chest. Thus, animals may only have a small amount of blood present in the chest cavity. These animals may not present as an emergency with breathing problems, but they still may have a serious underling disease process. Making the diagnosis of a hemothorax is critical in establishing an underling cause.
If the animal has normal clotting parameters the bleeding into the chest will, many times, stop on it’s own. Blood clots form that stop the bleeding. 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 hemothorax due to chest trauma, the bleeding will stop on it’s own.