Emergency Medical Technician (EMT) Practice Test

What happens when a thrombus forms?

1. Blood pressure decreases

2. Blood vessel bursts

3. Clot forms and blocks off circulation

4. Heart rate increases

The correct answer is: Clot forms and blocks off circulation

When a thrombus forms, it results in a clot that can obstruct blood flow within a blood vessel. A thrombus is essentially a blood clot that has formed within a blood vessel and can be a significant medical concern. When this clot blocks circulation, it may prevent oxygen and essential nutrients from reaching tissues, which can lead to serious complications, such as tissue death or organ dysfunction, depending on the location of the blockage. In some scenarios, if the thrombus grows large enough, it can completely occlude the vessel, resulting in reduced blood supply to downstream tissues. The other options describe potential consequences of blood vessel issues but do not accurately describe the direct effect of thrombus formation. Blood pressure may fluctuate due to various factors, a blood vessel bursting is more indicative of an aneurysm or severe trauma rather than thrombus formation, and while heart rate could be influenced indirectly by various circulatory issues, it does not directly reflect the phenomenon of thrombus formation itself.