What is the correct cuff pressure used during the Simplate Bleeding Time Test?

• A. 20 mmHg
• B. 30 mmHg
• C. 40 mmHg
• D. 50 mmHg

Answer: (C)

Bleeding time testing relies on a standardized condition where the arm is cuffed to occlude venous outflow while still allowing arterial inflow. Setting the cuff at 40 mmHg achieves that balance: it stops venous drainage, which helps produce a reproducible bleed that reflects platelet function, but it doesn’t compress the brachial artery, so arterial inflow continues and the wound bleeds in a controlled way. If the pressure were lower, venous outflow wouldn’t be adequately occluded, making results more variable and often shorter. If it were higher, arterial inflow could be hindered, lengthening the bleed time and causing unnecessary discomfort or ischemia. Therefore, 40 mmHg is the standard, best setting for this test.