ARDMS (American Registry for Diagnostic Medical Sonography) Practice Test

Which statement is true regarding these images?

1. The blood flow represented in these vessels is considered to be laminar flow.

2. The Reynolds number in these vessels is likely more than 2,000.

3. The blood flow represented in these vessels will be chaotic.

4. Eddy currents will likely be present within these blood vessels.

The correct answer is: The blood flow represented in these vessels is considered to be laminar flow.

The correct answer is A. The blood flow represented in these vessels is considered to be laminar flow. In laminar flow, the blood moves in a smooth, orderly manner in contrast to turbulent flow, where the flow is chaotic and irregular. In vessels with laminar flow, the layers of blood flow parallel to each other without significant mixing between them. This type of flow is characterized by low Reynolds number, which is typical for most blood flow in normal vessels. Reynolds number is a dimensionless value that helps predict flow patterns in different fluid flow situations. For blood flow in normal vessels, the Reynolds number is typically less than 2,000, making option B incorrect. Option C states that the blood flow represented in these vessels will be chaotic, which is incorrect as stated above. Option D mentions the presence of eddy currents in the blood vessels, which are typically associated with turbulent flow, not laminar flow as depicted in the images. Hence, option D is incorrect.