Comparison of Vacuum Pressure Syringe Aspiration Technique with Penumbra Aspiration Thrombectomy System: an In Vitro Study

Objective: In aspiration thrombectomy, a 60-mL syringe has a higher aspiration force than a 20 inHg aspiration pump. The recommended pressure of a new pump (Penumbra Pump MAX) is 28.5 inHg. We evaluated and compared the negative pressure flow rates during aspiration from locked syringes to the Penumbra Pump MAX. We also sought to determine how an increase in syringe volume affects the duration and volume of aspiration phases. Methods: A Penumbra Pump MAX, a 60-mL VacLok negative pressure syringe, and a 100-mL syringe were used as negative pressure generators and were connected to catheters. The pump was allowed to reach its peak negative pressure at 28.5 inHg before aspiration. The 100-mL syringe was pulled to 60, 70, 80, and 90 mL and locked. The mean flow rates (mL/s) and standard deviations were calculated. Results: The 60-mL syringe created higher flow rates than the Penumbra Pump MAX at 28.0 inHg (5.51 vs. 5.01 mL/s). Every 10 mL increase in syringe volume extended the plateau phase by 2 s without altering the flow rate, acceleration phase, or deceleration phase. Conclusion: The aspiration power of the two negative pressure generators was comparable. Increasing syringe volume directly increases the effective aspiration time.