What does Pre-pump arterial pressure measure?

• A. Pressure after the pump
• B. Pressure before the blood enters the pump from the access
• C. Venous pressure in the return line
• D. Average circuit pressure

Answer: (B)

Pre-pump arterial pressure is the pressure in the arterial access line just before the blood enters the pump. It tells you how hard it is to draw blood from the patient into the dialysis circuit and reflects the status of the access itself (needle position, clotting, kinking, infiltration, or other access problems). This measurement helps ensure adequate flow and early detection of access issues. It is different from the pressure after the pump and from the pressure in the return venous line, and it isn’t the circuit’s average pressure.