A hematoma is a collection of blood outside of a blood vessel. It occurs because of an injury to the wall of a blood vessel, allowing blood to leak out into the surrounding tissues. Small hematomas may resolve on their own, but larger ones can worsen and cause serious complications if not treated properly.
What is a hematoma?
A hematoma forms when a blood vessel gets damaged and blood leaks out. Blood pools in the surrounding tissues, forming a swelling or bruise. Common causes of hematomas include:
- Blunt trauma – a physical blow to the body from a fall, sports injury, accident, etc.
- Surgery – blood vessels may be severed during surgical procedures
- Blood thinners – anticoagulant medications prevent blood clotting, increasing bleeding
- Blood disorders – diseases like hemophilia impair blood clotting
- Vascular malformations – abnormalities of blood vessels that prone to leakage
Hematomas can occur anywhere in the body. Some of the most common sites include:
- Scalp – “goose egg” bump after a head injury
- Ear – “cauliflower ear” in wrestlers or boxers due to trauma
- Eyelid – “black eye” after an injury to the eye area
- Nose – bruising and swelling after nasal trauma
- Arms and legs – after an injury or intravenous line placement
- Buttocks and hips – in patients on blood thinners or after falls
- Abdomen – after surgery, injury, or even vigorous coughing
- Vaginal – after childbirth or surgical procedures
What happens as a hematoma worsens?
A hematoma will normally stabilize in size within a few hours after the initial bleeding. In some cases, it may continue to expand or worsen over the next several days to weeks. Here is what may occur as a hematoma gets bigger:
- Increased swelling & pain – The area becomes more swollen, firm, and painful as additional bleeding enlarges the hematoma.
- Spreading – The blood can spread along tissue planes, enlarging the hematoma further away from the original site.
- Compression – Expanding hematomas can compress nerves and blood vessels. This can cause numbness, tingling, coolness, and poor perfusion in the distal body part.
- Infection – Hematomas provide an ideal medium for bacterial growth, increasing infection risk.
- Calcification – Over time, the pooled blood calcifies into a hardened mass.
- Compartment syndrome – Increased pressure inside an enclosed muscle compartment can damage nerves, vessels, and muscles.
- Skin necrosis – The expanding hematoma can cut off blood supply to the overlying skin, causing tissue death.
- Septicemia – Bacteria from an infected hematoma can spread into the bloodstream, causing life-threatening sepsis.
- Hypovolemic shock – Significant blood loss into a large hematoma can result in low blood pressure and shock.
- Death of surrounding tissue – Compression, infection, or impaired blood supply can lead to permanent damage of muscles, nerves, skin, or organs.
Specific types of worsening hematomas
Subdural hematoma
A subdural hematoma occurs when blood pools between the dura mater and brain. It is most often caused by head trauma. As a subdural hematoma expands, it can compress the delicate brain tissue, resulting in:
- Worsening headache
- Nausea and vomiting
- Confusion and sleepiness
- Weakness on one side of the body
- Vision changes or loss of consciousness
- Life-threatening brain herniation
Retroperitoneal hematoma
The retroperitoneum refers to tissues behind the abdominal lining. A hematoma in this area is a common complication of surgeries, trauma, or anticoagulation. As it enlarges, it can cause:
- Severe abdominal, back, and/or leg pain
- Nerve compression causing numbness and weakness in the legs
- Hypovolemia and shock from blood loss
- Hypotension and kidney failure from compression of blood vessels
Rectus sheath hematoma
Rectus sheath hematomas involve bleeding into the compartment of abdominal muscles. Causes include coughing, vomiting, coagulopathy, and abdominal injuries. If untreated, worsening rectus sheath hematomas may develop:
- Worsening abdominal pain, swelling, and bruising
- Hypotension
- Abdominal compartment syndrome
- Myocardial infarction or arrhythmias from pressor release
- Peritonitis from abdominal wall ischemia
Risk factors for deterioration
Certain factors increase the chances of a hematoma expanding and causing complications:
- Anticoagulant use – blood thinners like warfarin prevent clotting needed to stabilize the hematoma.
- Large hematoma size – the bigger it is initially, the more it can expand.
- Delayed treatment – faster treatment limits further bleeding and complications.
- High impact site – the head, abdomen, and muscles have less space to accommodate swelling.
- Older age – decreased perfusion can impair healing.
- Bleeding disorders – impair the body’s ability to achieve hemostasis.
- Infection – bacteria accelerate tissue damage and complications.
Diagnosing a worsening hematoma
Doctors use a combination of assessment techniques to evaluate a hematoma including:
- Physical exam – inspection, palpation for swelling/firmness, assessment of pain, sensation, and perfusion.
- Patient history – onset, trauma mechanism, medical issues, medications.
- Imaging – CT, MRI, ultrasound to visualize size and location.
- Lab tests – CBC, PT/INR, chemistry to assess blood counts, clotting, organ function.
Worsening is indicated by increased swelling, pain, firmness, redness, warmth, numbness/tingling, or impaired perfusion on exam over time. Imaging can confirm increasing size. Labs may reflect blood loss anemia or poor organ perfusion.
Treating a progressing hematoma
Treatment focuses on halting bleeding, relieving compression, preventing complications, and allowing proper healing. Options include:
- Pressure – direct pressure stops bleeding in some cases.
- Surgical drainage – relieves pressure and allows removal of blood clots.
- Blood transfusions – replace blood loss from large hematomas.
- Medications – IV fluids, clotting factors, antibiotics if needed.
- Reducing anticoagulation – holds or reverses blood thinners until stabilized.
- Compression garments – helps prevent re-bleeding and swelling after surgery.
- Physical therapy – regains motion and strength after compression injuries.
With rapid, appropriate treatment, the outlook for most progressing hematomas is good. But delays can result in permanent nerve damage, muscle dysfunction, and tissue death.
Conclusion
Most small hematomas resolve without issue. But larger or expanding hematomas can compromise vital structures and functions. Worsening is indicated by increased swelling, pain, numbness, tissue damage, and blockage of nerves and vessels on exam. At risk groups include older patients, those on anticoagulants, or with bleeding disorders. Rapid diagnosis and treatment is key to prevent potentially devastating complications of a progressing hematoma. Options include surgical drainage, blood transfusions, medication reversal, and compression. Close follow up is important to monitor for improvement or deterioration.