Blood clots are semisolid clumps of blood that form in veins or arteries. Being aware of the signs and symptoms can help people seek treatment if they experience them.
A blood clot may be stationary (known as a thrombus) and block the flow of blood. Or, it might break free (known as an embolism) and travel through the body.
Keep reading for more information on the signs and symptoms of blood clots and how a doctor may treat them.
Certain people are at higher risk of developing a blood clot. According to the American Society of Hematology (ASH), factors that increase a person’s risk of developing blood clots include:
- taking oral contraceptives
- immobility, for example, during long hospital stays
- having obesity
- being over the age of 60 years
- family history of blood clots
- previous central line placement
- certain cancers
- chronic inflammatory diseases
People at risk for developing blood clots should be aware of the associated signs and symptoms. According to the American Blood Clot Association, symptoms vary depending on the type of blood clot.
Deep vein thrombosis (DVT) is a clot that typically occurs in a major vein in the leg, but it can also develop in the pelvis or arm.
DVT may not cause any symptoms, but if symptoms do occur, they can include:
- warmth at the site of the clot
- tenderness or pain in the affected leg or arm
- swelling in the affected leg and foot or arm and hand
- skin turning red or purple
Symptoms are often local to the blood clot and only affect one arm or leg. The National Blood Clot Alliance add that the pain or discomfort of this type of blood clot may be similar to the sensation of a pulled muscle.
A pulmonary embolism occurs when a clot or part of a clot travels through the veins and ends up in the lungs. This condition can be deadly.
According to the American Blood Clot Association, some common symptoms of a pulmonary embolism include:
- sharp pain in the chest, particularly when taking a deep breath
- a cough that produces blood
- rapid pulse
- sudden shortness of breath
- unexplained sweating
A person should seek emergency help immediately if they experience any signs of a pulmonary embolism.
Arterial clots typically produce symptoms quickly because they begin cutting off oxygen to organs faster than other types of blood clots. They can cause various symptoms and complications, including heart attack, stroke, severe pain, and paralysis.
Although DVT and pulmonary embolisms are common, blood clots can occur in other areas of the body.
According to the ASH, blood clots in other parts of the body may cause the following symptoms:
The diagnostic process can vary depending on the location of the suspected clot.
A doctor may ask questions about the person’s symptoms and perform a physical examination.
According to the National Blood Clot Alliance, some typical tests include:
- ultrasound, which doctors typically use to diagnose DVT
- venography, which uses a dye to show blood flow in the veins
- MRI scan
- pulmonary angiogram, in which doctors use dye and an X-ray of the chest to determine whether a pulmonary embolism is present
Doctors may use a CT angiography test to check for clots in the head, neck, chest, or abdomen. The test involves the injection of a contrast material into the blood and computer imaging to show blood flow and reveal any clots.
A doctor may order an X-ray of the chest to rule out other possible causes of some pulmonary embolism symptoms, such as pneumonia.
Treating blood clots involves reducing the size of the clot and preventing new clots from forming.
Typical treatments for blood clots include:
- anticoagulant medications called blood thinners, which help prevent new clots and stop existing clots from growing
- thrombolytic therapy to dissolve clots
- compression stockings
- vena cava filters, which are small devices that a surgeon can insert into veins to prevent a clot from traveling to the lungs
A person should talk to their doctor about their treatment options. When using medications, they should take the dosages that their doctor prescribed.
Certain medications, such as blood thinners, can help treat blood clots and prevent further clots from forming. Compression socks are also a helpful preventive measure.
Although not all blood clots are avoidable, a person can take steps to help prevent them. According to the Agency for Healthcare Research and Quality, these steps include:
- raising the legs 6 inches above the heart on occasion during bed rest
- wearing loose-fitting stockings, clothes, or socks
- staying active and following an exercise regimen
- wearing compression stockings regularly
- limiting salt in the diet as much as possible
- shifting positions frequently when stationary for extended periods
- avoiding sitting or standing for more than 1 hour at a time
- taking all medication as the doctor prescribed
- avoiding placing pillows under the knees
- refraining from crossing the legs
- trying to avoid bumping or injuring the legs
Blood clots can cause serious medical issues. If a blood clot breaks free, it can move to the lungs, heart, or brain, blocking blood flow to these vital organs. A person may experience a stroke or heart attack.
Blood clots are common in pregnancy, often due to limited mobility. If a blood clot occurs during pregnancy, it can lead to complications such as:
- placental insufficiency, which means that the placenta does not provide enough nutrients and oxygen to the fetus
- a blood clot in the placenta, which can cause harm to the fetus
- intrauterine growth restriction, which prevents the fetus from growing properly
These possible complications are in addition to those that are common in all people, including:
- thrombosis or a blockage, such as DVT or cerebral vein thrombosis (CVT), which occurs when the clot forms in the brain
- pulmonary embolism
- heart attack
- venous thromboembolism
Blood clots can form almost anywhere in the veins or arteries. If they occur, they can cause complications such as heart attack and stroke.
People should be aware of their risk factors for developing a blood clot, which can include obesity, being stationary for extended periods, and pregnancy.
People should talk to their doctor if they experience symptoms that could be due to a blood clot.