Surgical fluid evacuator

A fluid evacuation device, comprising:

• a compressible reservoir, comprising:
• a pair of structural articulated walls, each of said walls comprising a central wall member and a pair of wing wall members, said wing wall members hinged to said central wall member on opposite sides thereof, said central wall member and said respective wing wall members shaped to form trapezoidal cut-outs on opposite sides of each of said articulated walls;
• a flexible membrane spanning over and across each of said cut-outs to seal the area between said walls from the atmosphere;
• spring means interposed between said walls for biasing said walls apart to expand said reservoir and create a vacuum therein, said spring decreasing in force as said reservoir expands and oriented with the spring axis in the direction of expansion of said reservoir, said wing members pivoting with respect to said central member as said articulated walls are biased apart by said spring means to decrease the component of atmospheric forces acting on said wing members in the direction of the force of said spring means, to at least partially offset the decreasing force of said spring means to reduce changes in reservoir vacuum;
• and
• a fluid collection tube, connected to said reservoir, for conducting fluid from a wound to said reservoir.

A surgical fluid evacuator, comprising:

• a reservoir, comprising:
• a first articulated wall;
• a second articulated wall;
• and
• means for sealing an area between said first and second articulated walls to form a reservoir between said walls while permitting said articulated walls to spread apart;
• means for biasing said articulated walls apart to create a vacuum for drawing fluid into said reservoir;
• a latch, internal to said reservoir, for holding said walls together with virtually no space therebetween, said latch releasable to permit said first and second articulated walls to spread apart;
• and
• a fluid collection tube, connection to said reservoir, for drawing fluid from a wound to said reservoir.

A fluid evacuation device, comprising:

• a reservoir, comprising:
• a first articulated wall;
• a second articulated wall;
• and
• flexible wall means for sealing an area between said first and second articulated walls to form a reservoir between said walls while permitting said articulated walls to spread apart;
• means for biasing said articulated walls apart to create a vacuum for drawing fluid into said reservoir;
• and
• a latch, internal to said reservoir, adapted to selectively hold said articulated walls together with virtually no space therebetween, said reservoir pre-evacuated with respect to the atmosphere to assist said latch in holding said articulated walls together and to prevent deformation of said latch when said surgical evacuator is stored.

A fluid evacuation device, comprising:

• a reservoir, comprising:
• a first articulated wall;
• a second articulated wall;
• and
• flexible wall means for sealing the area between said first and second articulated walls to form the reservoir between said walls while permitting said articulated walls to spread apart;
• means for biasing said articulated walls apart to create a vacuum for drawing fluid into said reservoir;
• a fluid collection tube, connected to said reservoir, for conducting fluid from a wound to said reservoir;
• and
• a latch, internal to said reservoir, adapted to selectively hold said articulated walls together with virtually no space therebetween, said latch comprising:
• a first latch hook on said first articulated wall;
• a second latch hook on said second articulated wall;
• a first biasing tab on said first articulated wall;
• a second biasing tab on said second articulated wall;
• and
• said first hook cooperating with said second biasing tab and said second hook cooperating with said first biasing tab to engage said hooks when said first articulated wall is pressed against said second articulated wall.

A fluid evacuation device, comprising:

• a reservoir, comprising:
• first articulated wall means comprising a first wing wall member pivotally connected to a first central wing member by a first hinge;
• second articulated wall means comprising a second wing wall member pivotally connected to a second central wall member by a second hinge, said first and second wing wall members fastened together to prevent them from sliding relative to each other, said first and second hinges positioned to permit said wing wall members to pivot relative to said central wall members and formed to force said first and second central wall members to slide relative to each other when said first and second wing wall members pivot relative to said central wall members;
• and
• flexible wall means for sealing the area between said first and second articulated wall means to form said reservoir between said wall means while permitting said articulated wall means to spread apart;
• means for biasing said articulated wall means apart to create a vacuum for drawing fluid into said reservoir, said articulated wall means formed to permit them to lie flat against each other when said biasing means is compressed;
• a fluid collection tube, connected to said reservoir for conducting fluid from a wound to said reservoir;
• and
• latch means internal to said reservoir, for selectively holding said first and second articulated wall means together with virtually no space therebetween, said latch means disengaged by said relative sliding of said central wall members.

A surgical evacuation device, comprising:

• a compressible skeletal articulative mechanism;
• a flexible membrane conforming in shape to said skeletal mechanism for sealing said skeletal mechanism to the atmosphere to form a reservoir, said skeletal mechanism providing a structure for controlling the shape of said reservoir;
• a fluid collection catheter sealed to said membrane;
• and
• means for biasing said skeletal mechanism to expand said reservoir to draw fluid through said catheter into said reservoir, said biasing means providing a biasing force in the direction of expansion of said reservoir, said force decreasing as said skeletal mechanism expands, the expansion of said skeletal mechanism changing the shape of said reservoir to reduce the component of atmospheric forces directed parallel to said biasing force to at least partially offset for decreases in said biasing forces.

A fluid evacuator for drawing fluid from a wound, comprising:

• a pair of structural articulated plates;
• an expandable reservoir for containing fluid, said reservoir providing means for sealing the area between said plates from the atmosphere, and conforming to the configuration of said plates as said reservoir fills;
• a spring, interposed between said plates and compressed to provide biasing force, in the direction of expansion of said reservoir, to bias said plates apart to expand said reservoir and create a vacuum therein, said spring force in the same direction as said biasing force and decreasing as said reservoir expands;
• said plates interacting with said spring and said reservoir to cause the component of atmospheric forces on said reservoir in a direction parallel to said spring biasing force to decrease as said reservoir expands, and to cause the component of atmospheric forces acting on said reservoir in a direction perpendicular to said spring biasing force to increase as said reservoir expands, to provide a supplementary force to assist said spring in biasing said plates apart, said supplementary force increasing as said reservoir expands, said decreasing atmospheric force and said increasing supplementary force cooperating with the force of said spring to reduce changes in said vacuum as said reservoir expands;
• and
• a fluid collection tube, for conducting fluid into said reservoir.

A surgical fluid evacuator, comprising:

• a reservoir, comprising:
• a pair of structural articulated plates;
• flexible wall means for sealing the area between said plates from th atmosphere to form a reservoir between said walls while permitting said plates to spread apart;
• a fluid collection catheter for conducting fluid into said reservoir;
• and
• spring means interposed between said plates, said spring means biasing said plates apart to expand said reservoir and create a vacuum therein, said plates controlling the geometry of said reservoir during expansion to provide at least partial compensation for changes in said vacuum caused by changes in the force of said spring means as said spring means expands, said compensation providing a substantially constant vacuum.

A surgical fluid evacuator, comprising:

• a reservoir;
• a fluid collection catheter for conducting fluid into said reservoir;
• and
• a spring, disposed within said reservoir, having coils comprised of wire having a uniform wire diameter, said spring providing a force to bias the walls of said reservoir to create a vacuum therein, said coils formed to permit them to nest within each other when fully compressed, and formed to permit all of said coils, when compressed, to be active.

A method of controlling changes in vacuum in a surgical evacuation reservoir, comprising:

• biasing said reservoir to expand, using a spring which provides a biasing force in the direction of expansion of said reservoir;
• causing said biasing force to reduce at a first predetermined rate as said reservoir expands;
• reducing the effective area of said reservoir, projected in the direction of said biasing force of said spring, at a second predetermined rate as said reservoir expands;
• and
• coordinating said first and second predetermined rates to limit changes in said vacuum in said reservoir.