摘要 |
A filter apparatus incorporating an integral variable flow control mechanism has a housing 10 with an inlet 12 and an outlet 14 between which is arranged a filter 16. A structure 26 defining a flow channel between the inlet and the outlet is mounted within the housing; and a tube movable relative to the housing is coupled to the inlet or outlet, preferably by a screw thread. A closure member 28 is located either on the structure or on an internal end of the tube (figure 2A), such that the tube can be moved between a fully open position permitting through flow and a closed position in which it seats against the structure. Intermediate positions throttle the rate of fluid flow. Preferably a smoke evacuation catheter is attached to the external end of the tube and rotation of the housing is used to adjust the flow rate. Markings on the outside of the housing may indicate the relative venting rate associated with any particular position. The filter is for use in laparoscopic surgery. |