Why should BP not be measured over clothing?

• A. Clothing can dampen cuff inflation and cause measurement artifacts, leading to inaccurate readings.
• B. Clothing improves insulation and improves accuracy.
• C. Clothing reduces patient comfort but does not affect readings.
• D. Clothing increases cuff pressure.

Answer: (D)

The key idea is that the cuff must be in direct contact with the skin for the cuff’s pressure to be accurately transmitted to the artery. When fabric from clothing sits between the cuff and the arm, it adds a cushion that the cuff has to compress. This extra layer alters the effective pressure reaching the brachial artery, creating artifacts and usually producing a higher-than-true reading. That’s why BP should not be measured over clothing—the measurement depends on a proper, direct cuff-to-skin interface to be reliable.

Clothing can’t improve accuracy; it can distort it. It doesn’t merely affect comfort in a way that leaves readings unchanged. And while clothing can lead to an appearant increase in the pressure you record, the core issue is the dampened, artifact-prone transfer of cuff pressure due to the fabric, not a fixed, simple increase.