US Pharm. 2020;45(2):13-14. 

A Thrombis Is Life-Threatening

Blood clots are a natural part of the healing process. When an injury damages a blood vessel enough to cause bleeding, your blood will form clots to slow the blood flow and prevent blood loss. Once your injury heals, the body naturally breaks down the blood clot that is no longer needed. Sometimes, due to an underlying medical condition, blood clots form when they are not necessary or do not break down as they should. When these abnormal blood clots form inside of your veins and arteries, it is called a thrombus. A thrombus that blocks blood flow is an emergency and can result in significant tissue damage or even death.

Clots Can Block Blood Flow to Organs

 There are two different types of blood clots—a thrombus and an embolus. A thrombus forms and stays in place. It can grow large enough to cut off blood flow through the vessel. Without a blood supply, the tissue becomes damaged. Eventually, the tissue will die if the blood supply is not restored. A thrombus that forms in the blood vessels of the heart can cause a heart attack. When a thrombus forms in the blood vessels of the brain, it can cause a stroke.

An embolus is a thrombus, or a piece of a blood clot, that comes loose and travels through the bloodstream and can become lodged in a smaller vessel down the line. An example is a clot that forms in the deep veins of the legs or arms that breaks off and travels to the lungs, called a pulmonary embolism. A thrombus can also develop in the atria, a chamber of the heart, in people with atrial fibrillation. The clot can travel out of the heart (an embolus) and travel to the brain and cause a stroke.

Timely Diagnosis Is Critical

Restoring blood flow should happen as quickly as possible, which is why a person who has a heart attack or stroke is rushed to a hospital for emergency care.

The diagnosis of a blood clot is made using the information from the patient’s medical history and physical symptoms. An ultrasound image will show the areas where blood flow is blocked through the blood vessels. An electrocardiogram (ECG) and laboratory tests can help confirm the diagnosis of a heart attack. Both computed tomography (CT scan) and magnetic resonance imaging (MRI) use an injectable dye to show blood flow through the arteries. In the case of a stroke, a scan with dye helps visualize whether the condition is due to bleeding, a tumor, or a blood clot. In a heart attack, these scans help show the areas where blood flow to the coronary artery is slowed or stopped.

Treating Life-Threatening Clots

Medication is used to treat a clot and to prevent clots from forming in individuals who have an increased risk. In emergency situations where a clot has formed and is blocking a major blood vessel, the main goal is to open up the blood vessel and restore blood flow. Medications called thrombolytics, or clot busters, are given in life-threatening situations to dissolve a clot (thrombolysis). There are two ways that clot-busting agents are administered: through an IV or a catheter (thin tube) directly at the site of the clot. Owing to their ability to effectively break down blood clots, the main risk factor for thrombolytic medication use is bleeding.

Medications to Prevent Future Blood Clots

Once the clots are dissolved, anticoagulant medications (blood-thinners) are used to prevent more clots from forming. If your doctor has prescribed daily aspirin, antiplatelet drugs, anticoagulants, or other drugs to prevent blood clots, heart attack, stroke, or deep vein thrombosis, be sure to take them regularly as directed. Speak with your doctor if you are experiencing any side effects, such as abnormal bleeding and bruising.

Your pharmacist can answer any questions you may have about these and all your medications.

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