| 摘要 |
An aspiration system (10) having pressure-controlled and flow-controlled modes comprises connective plumbing (26), a collector (14), a pump (12), a variable flow resistor (20), a pressure sensor (18), and a control circuit (24). The connective plumbing (26) includes a conduit (28) which communicates with the surgical site from which fluid is to be aspirated and delivered to the collector (14). The pump (12) induces flow from the surgical site to the collector (14). The variable flow resistor (20) and the pressure sensor (18) are in fluid communication with the conduit (28) by the connective plumbing (26). In the pressure-controlled mode, the variable flow resistor (26) is adjusted to maintain a pre-selected pressure according to an output signal (50) from the pressure sensor (18). In the flow controlled mode, the pump (12) is adjusted to maintain a preselected flow according to a pressure differential in the connective plumbing across the variable flow resistor (20). The system (10 ) further includes a gas source (22) which is inputted into the variable flow resistor (20) to provide a known pressure against which the pressure in the remainder of the connective plumbing is compared to establish the pressure differential. The connective plumbing (26) further includes a flow director (16) permitting flow only in one direction to avoid contamination of certain portions of the connective plumbing (26). The contaminated portions of the connective plumbing (26) are discarded. |
