Surgical instrument having self-regulated vapor condensation heating of its cutting edge and method of using the same

Claim 2

A blade comprising: a cutting means including a cutting edge and thermal distribution means disposed adjacent the region of said cutting edge; said thermal distribution means including a fluid-tight chamber containing therein a material which has both vapor and liquid stages within a selected temperature range; said chamber being adapted to be heated in a selected region thereof to an elevated temperature at which said material attains the vapor state; said chamber providing a channel therein which is thermally coupled to said cutting edge and which transports vapor from the location of said selected region to other locations within the chamber at which conversion from the vapor to the liquid state of said material may occur; said chamber including therein transport means for transporting liquid back to said selected region.

Claim 3

A blade as in claim 1 wherein said transport means supports capillary action of the liquid and is disposed contiguous the inner walls of the chamber in the region of said channel.

Claim 4

A blade as in claim 1 wherein said selected region is disposed along the length of the chamber walls in the region which is opposite to the region of the chamber walls which are located adjacent the cutting edge.

Claim 5

A blade as in claim 1 wherein said selected region is disposed along the length of the chamber contiguous the portion of the walls thereof which is not adjacent to said cutting edge.

Claim 6

A blade as in claim 1 comprising heating means to heat said selected region of said chamber.

Claim 7

A blade as in claim 1 comprising insulating means disposed about the portions of the walls of the chamber except the portion adjacent the region of the cutting edge.

Claim 8

A blade as in claim 1 comprising: sensing means coupled to said chamber for producing a control signal which is representative of one of the pressure and temperature of the chamber; and means coupled to the sensing means and to said heating means for altering the power output of the heating means in response to said control signal.

Claim 9

A blade as in claim 1 wherein a portion of said chamber is located remotely from the cutting edge and includes a volume which is larger than the portion of the chamber which is adjacent the region of said cutting edge for providing thermal inertia for said cutting edge.

Claim 10

A blade as in claim 1 comprising: sensing means coupled to said chamber for producing a control signal which is representative of the pressure of the chamber; and means coupled to the sensing means and to said heating means for altering the power output of the heating means in response to said control signal.

Claim 11

A blade as in claim 1 comprising cooling means thermally coupled to said chamber for selectively altering the temperature of said cutting edge.

Claim 12

A hemostatic cutting blade comprising: a cutting means including a cutting edge and thermal distribution means disposed adjacent the region of said cutting edge; said thermal distribution means including a fluid tight chamber containing therein a material which has vapor and liquid states within a temperature range between about 300° C. to about 1000° C.; said chamber being adapted to be heated in a selected region thereof to an elevated temperature at which said material attains the vapor state; said chamber providing a channel therein which is thermally coupled to said cutting edge and which transports vapor from the location of said selected region to other locations within the chamber at which conversion from the vapor to a liquid state of said material may occur; said chamber including therein transport means for transporting liquid back to said selected region.

Claim 13

A hemostatic cutting blade comprising: a cutting means including a cutting edge and thermal distribution means disposed adjacent the region of said cutting edge; said thermal distribution means including a fluid tight chamber containing therein a material which has vapor and liquid states within a temperature range between about 300° C. to about 1000° C.; said chamber being adapted to be heated in a selected region thereof to an elevated temperature at which said material attains the vapor state; said chamber providing a channel therein which is thermally coupled to said cutting edge and which transports vapor from the location of said selected region to other locations within the chamber at which conversion from the vapor to a liquid state of said material may occur; said chamber including therein transport means for transporting liquid back to said selected region.

Claim 14

A hemostatic cutting blade as in claim 11 wherein said material includes one of the elements selected from the group consisting of cesium, sodium, potassium, lithium and mercury.

Claim 15

A hemostatic cutting blade comprising: a cutting means having a cutting edge and thermal distribution means disposed adjacent the region of said cutting edge; said thermal distribution means including a fluid tight chamber containing therein a material which has liquid and vapor states within a selected temperature range; said chamber being adapted to be heated in a selected region thereof to an elevated temperature at which said material attains the vapor state; said chamber providing a channel therein which is thermally coupled to said cutting edge and which transports vapor from the location of said selected region to other locations within the chamber at which conversion from the vapor to a liquid state of said material may occur; said chamber including therein transport means for transporting liquid back to said selected region.

Claim 16

A hemostatic cutting blade comprising: a cutting means having a cutting edge and thermal distribution means disposed adjacent the region of said cutting edge; said thermal distribution means including a fluid tight chamber containing therein a material which has liquid and vapor states within a selected temperature range; said chamber being adapted to be heated in a selected region thereof to an elevated temperature at which said material attains the vapor state; said chamber providing a channel therein which is thermally coupled to said cutting edge and which transports vapor from the location of said selected region to other locations within the chamber at which conversion from the vapor to a liquid state of said material may occur; said chamber including therein transport means for transporting liquid back to said selected region.

Claim 19

A method of cutting as in claim 14 wherein in the step of selectively varying the thermal coupling, heated vapor is transported from the heat source to locations adjacent regions of the cutting edge where the vapor is condensed to liquid for return to the heat source for heating and vaporization.

Claim 22

A method of cutting as in claim 16 wherein in the step of vaporizing fluid, heat from a heat source is applied to the chamber at at least one of the locations near one end of the chamber, and the location along the chamber in regions thereabout which are substantially opposite the cutting edge.