Abstract:
Surgical cooling may be implemented by various systems, processes, and techniques. In certain implementations, a surgical cooling device includes a shaft, a cooling assembly, and a mechanical control system. The shaft includes a pair of axial cooling channels extending through its interior. The cooling assembly includes a pair of arms pivotally attached to the shaft and a foldable thermal exchanger coupled to the pair of arms and fluidly coupled to the pair of axial cooling channels. The mechanical control system is adapted to unfold the cooling assembly from a closed position to an open position to allow a coolant to flow through a first of the pair of axial cooling channels, through one or more thermal exchange channels, and out a second of the pair of cooling channels.

Description:
RELATED APPLICATIONS 
       [0001]    This application is a 371 of PCT Application No. PCT/US11/45261, entitled “Surgical Cooling Device” and filed on Jul. 25, 2011, which claims priority to U.S. Provisional Application No. 61/367,252, entitled “Surgical Cooling Device” and filed on Jul. 23, 2010. These applications are herein incorporated by reference. 
     
    
     BACKGROUND 
       [0002]    This invention relates to the field of medicine and more particularly to a surgical cooling device. The present invention is useful for cooling organs attendant to surgery. For example, in partial nephrectomies, the kidney is often cooled prior to performing the surgery. This specification describes a novel surgical cooling device useful in surgeries where organ cooling is desired. It may be applied in any setting by any approach (open, laparoscopic, robotic and/or any minimally invasive approach) on any organ where surface hypothermia is desired. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0003]      FIG. 1  is a perspective view of a surgical cooling system with a surgical cooling device. 
           [0004]      FIG. 2  is a cut-away perspective view of a surgical cooling device with the cooling assembly in an open position. 
           [0005]      FIG. 3  is a cut-away perspective view of a surgical cooling device with the cooling assembly in a closed position. 
           [0006]      FIG. 4  is an exploded view of a surgical cooling device (thermal exchanger not shown). 
           [0007]      FIG. 5  is a top view of a cooling assembly in an open position. 
           [0008]      FIG. 6  is a perspective view of a surgical cooling device (handle assembly not shown) with the cooling assembly in a closed position. 
           [0009]      FIG. 7  is a top view of a surgical cooling device (handle assembly not shown) with the cooling assembly in an open position. 
           [0010]      FIG. 8  is a perspective view of a surgical cooling system with an alternative embodiment of a surgical cooling device. 
           [0011]      FIG. 9  is a top view of an alternative surgical cooling device. 
           [0012]      FIG. 10  is an enlarged perspective view of an alternative embodiment of a surgical cooling device (thermal exchanger not shown). 
           [0013]      FIG. 11  is a top view of an alternative embodiment of a surgical cooling device with the arms in the open position (thermal exchanger not shown). 
           [0014]      FIG. 12  is a top view of an alternative embodiment of a surgical cooling device with the arms in the closed position (thermal exchanger not shown). 
           [0015]      FIG. 13  is a perspective view of an alternative embodiment of a surgical cooling device (thermal exchanger not shown). 
           [0016]      FIG. 14  is an enlarged perspective view of an alternative embodiment of a surgical cooling device (thermal exchanger not shown). 
           [0017]      FIG. 15  is an enlarged side view of an alternative embodiment of a surgical cooling device (thermal exchanger not shown). 
           [0018]      FIG. 16  is an enlarged cross-section view of an alternative embodiment of a surgical cooling device (thermal exchanger not shown). 
           [0019]      FIG. 17  is an enlarged cross-section view of an alternative embodiment of a surgical cooling device (thermal exchanger not shown). 
       
    
    
     SUMMARY OF THE INVENTION 
       [0020]    The present invention is a surgical cooling device for cooling organs attendant to surgery. When the surgical cooling device is in use, a coolant circulates inside the device to cool the organ. 
         [0021]    An embodiment of the present surgical cooling device comprises a body having a handle and a shaft having a pair of axial cooling channels extending through the interior of the shaft; a cooling assembly comprising a pair of arms pivotally attached to the shaft and a foldable thermal exchanger mounted on the pair of arms and fluidly coupled to the pair of axial cooling, the thermal exchanger comprising an inlet port, an outlet port, and one or more exchange channels fluidly connecting the inlet port to the outlet port; and a mechanical control system for opening and closing the cooling assembly, the mechanical control system comprising a rotatable knob with a male threaded end, a plunger with a female threaded opening and an opening adapted to receive a rod, the rod engaging the plunger and a pair of wing connectors, the wing connectors attached to the rod and the pair of arms; wherein the cooling assembly unfolds from a closed position to an open position and folds from the open position to the closed position in response to rotation of the knob; and wherein a coolant flows through a first of the pair of axial cooling channels, through the one or more exchange channels, and out a second of the pair of cooling channels. 
         [0022]    An alternative embodiment of the present surgical cooling device comprises (A) a body including a handle, a shaft adjacent to the handle, a pair of shoulders adjacent to the shaft, and a pair of axial cooling channels extending through the interiors of the handle and the shaft, each of the pair of axial cooling channels having at least one inflow and one outflow port; and (B) a cooling assembly including a pair of arms pivotally attached to the pair of shoulders, a pair of fasteners attaching the pair of arms to the pair of shoulders, and a foldable thermal exchanger mounted on the pair of arms and engaging the pair of axial cooling channels; the thermal exchanger comprising an inlet port, an outlet port, one or more exchange channels fluidly connecting the inlet port to the outlet port, and a pair of sleeves at two edges of the thermal exchanger adapted to slip onto the pair of arms; wherein the cooling assembly unfolds from a closed position to an open position and folds from the open position to the closed position; and wherein a cooling media flows into a first of the pair of cooling channels, through the one or more exchange channels, and out a second of the pair of cooling channels. 
         [0023]    A surgical cooling device will now be described with more particular reference to the attached drawings. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0024]      FIG. 1  shows a surgical cooling system comprising one or more surgical cooling devices  200 , a chiller/pump system  510 , and one or more pairs of hoses or tubes  410 . Each pair of tubes  410  comprises an inlet tube for conveying coolant from the chiller/pump system  510  to a surgical cooling device  200  and an outlet tube for conveying coolant from the surgical cooling device  200  to the chiller/pump system  510 . Each tubing pair  410  fluidly connects one cooling device  200  to the chiller/pump system  510 . The one or more pairs of tubes  410  may be detachably engaged to the one or more cooling devices  200  or the chiller/pump system  510 . 
         [0025]    The surgical cooling system is a closed, self-contained system, with coolant circulating from the chiller/pump system  510 , through an inlet tube of a tubing pair  410 , through a surgical cooling device  200 , through an outlet tube of a tubing pair  410 , and back into chiller/pump system  510 . The chiller/pump system  510  circulates chilled fluid or other coolant, either continuously or in an intermittent manner, for cooling an organ to a desired temperature. Off-the-shelf equipment may be used for the chiller/pump system  510 , such as Tek-Temp Instruments, Inc.&#39;s LK-10 Light Capacity Chiller. The coolant flow rate and type of coolant may be varied according to the cooling needs of the specific surgery. 
         [0026]    As shown in  FIG. 1 , the surgical cooling device  200  may comprise a body  220  and a cooling assembly  210 . Body  220  may include a handle assembly  221 , a shaft  222 , and a knob  223 , all of which may be constructed of stainless steel, durable plastic, or other materials known in the art. Referring to  FIG. 2 , the cooling assembly  210  may comprise a pair of arms  211  and a thermal exchanger  212 . The total length of the surgical cooling device  200  may be about 300 millimeters (mm), but the total length may be varied as needed for placement of the cooling assembly  210  on the target organ. The surgical cooling device  200  may be capable of being deployed laparoscopically or in open surgeries. For example, the surgical cooling device  200  may be inserted into a trocar during use, so the diameter of shaft  222  and cooling assembly  210  (in the closed position) may be 12 mm or sized as needed to enter standard trocars. 
         [0027]    Referring to  FIG. 2 , the cooling assembly  210  comprises a pair of arms  211  and a thermal exchanger  212 . The thermal exchanger  212  may be connected to the pair of arms  211 . The design and properties of thermal exchanger  212  may be similar to the design and properties of thermal exchanger  112 , described in further detail below. In particular, the thermal exchanger  212  may be formed of foldable plastic containing a pattern of channels. The pair of arms  211  may be pivotally attached to the shaft  222  and will open into a generally V-shaped cooling surface. The pair of arms  211  may be mounted on an internal protrusion  241  in shaft  222 , with one arm mounted directly above the other, or mounted with a pin or fastener. Each arm of the pair of arms  211  may be about 150 millimeters in length. However, the pair of arms  211  need not be identical in length and may be sized as needed for the procedure.  FIG. 2  shows the pair of arms  211  in an open position. In the open position, the angle of separation between the pair of arms  211  may be about 90 degrees; however, this angle may be more or less as appropriate for the specific cooling application.  FIG. 1  shows the pair of arms  211  in a closed position, wherein the pair of arms  211  are approximately parallel. The pair of arms  211  may open either symmetrically or asymmetrically about the axis of body  220 . The pair of arms  211  may be made of the same material as body  220  or of a different suitable material. 
         [0028]    Shaft  222  contains a pair of axial cooling channels. The cooling channels may have cross-sections that are circular in shape, preferably about 5 to 6 mm in diameter. Although each of the cooling channels preferably possesses the same shape and cross-sectional area, the cooling channels may possess dissimilar shapes or cross-sectional areas. The axial cooling channels convey the coolant between the tubing pair  410  and the cooling assembly  210 . The thermal exchange  212  are fluidly coupled to the pair of axial cooling channels within shaft  222 . 
         [0029]    The cooling device  200  further comprises a plunger  224 , a rod  225 , a shaft cover  226 , and a pair of arm connectors  227 . The knob  223  has a male-threaded section that engages a female-threaded opening within plunger  224 . Knob  223  additionally comprises a rotation plate, which holds knob  223  in its axial position within the handle assembly  221  while allowing the knob  223  to rotate. The plunger of  224  moves axially in response to the rotation of knob  223 . One end of the rod  225  is connected to the plunger  224 , typically in a small opening opposite the threaded female opening of the plunger  224 . The opposite end of rod  225  connects to the pair of arm connectors  227 , typically using a pin or other fastener. The rod  225  passes through an axial rod channel in the shaft  222 . The shaft  222  contains a locking plate having a 90 degree cut-out, which holds the shaft  222  in its axial position within the handle assembly  221  and prevents rotation of the shaft  222 . One end of each of the pair of arm connectors  227  is connected to the rod  225  and the opposite end is connected to one of the arms  221 , typically using a pin or other fastener. The shaft cover  226  is attached to the shaft  222 .  FIG. 3 ,  FIG. 4 ,  FIG. 5 ,  FIG. 6 , and  FIG. 7  show further aspects of surgical cooling device  200 . Surgical cooling device  200  may be used in a manner similar to the use of surgical cooling device  100 , as described below. 
         [0030]      FIG. 8  shows a surgical cooling device  100  in a surgical cooling system. The surgical cooling system comprises one or more surgical cooling devices  100 , a chiller/pump system  500 , a graphical user interface  600 , and one or more hoses or tubes  400 . The one or more hoses or tubes  400  are coupled to the chiller/pump system  500  and detachably engage the one or more surgical cooling device  100 . The chiller/pump system  500  maintains coolant at the desired temperature and continuously pumps coolant into the one or more surgical cooling devices  100 . The coolant flow rate and coolant may be varied according to the specific surgery. The surgical cooling system is a closed, self-contained system with coolant circulating out of the chiller/pump system  500 , through the one or more hoses or tubes  400 , through the one or more surgical cooling devices  100 , back through the one or more hoses or tubes  400 , and into chiller/pump system  500 . The surgical cooling device  100  is capable of being deployed laparoscopically or in open surgeries, and may be reusable or disposed after a single-use. 
         [0031]      FIG. 9  discloses an embodiment of a surgical cooling device  100 . The surgical cooling device  100  comprises a cooling assembly  110  and a body  120 . Surgical cooling device  100  is Y-shaped when in the open position as shown in  FIG. 9 . Body  120  may include a handle  121 , a shaft  122 , and a pair of shoulders  123 , all of which are preferably made of plastic. Handle  121 , shaft  122 , and pair of shoulders  123  may be integrally manufactured, welded together, or coupled with fasteners such as screws. The total length of the surgical cooling device  100  is preferably about 300 millimeters (mm). However, the total length of surgical cooling device  100  may be optimized to allow precise extension to the target organ based on the application. 
         [0032]    When in use, the surgical cooling device  100  is capable of being inserted into and engaging a 12 mm diameter trocar. Accordingly, the diameter of body  120  is preferably at least 12 mm. Referring now to  FIG. 10 , body  120  further comprises typically a pair of axial cooling channels  125  running through handle  121  and shaft  122 . Each of the pair of cooling channels  125  has at least one inflow and one outflow port. The cooling channels  125  may have cross-sections that are circular in shape, preferably about 5.5 mm in diameter. Although each of the cooling channels  125  preferably possesses the same shape and cross-sectional area, the cooling channels  125  may possess dissimilar shapes or cross-sectional areas. 
         [0033]    Referring back to  FIG. 9 , the cooling assembly  110  comprises a pair of arms  111  and a thermal exchanger  112 . The pair of arms  111  may be pivotally attached to the pair of shoulders  123 . Fasteners  113 , such as locking pins or screws, mount the pair of arms  111  to the pair of shoulders  123 . Each arm of the pair of arms  111  is preferably about 150 millimeters in length. However, the pair of arms  111  need not be identical in length.  FIG. 9  and  FIG. 11  shows the pair of arms  111  in an open position. In the open position, the angle of separation between the pair of arms  111  in a preferred embodiment is about 90°; however, this angle may be more or less as required for the specific cooling application.  FIG. 12  shows the pair of arms  111  in a closed position, wherein the pair of arms  111  are approximately parallel. The pair of arms  111  may open either symmetrically or asymmetrically about the axis of body  120 . The pair of arms  111  may be made of the same material as body  120  or of a different suitable material. 
         [0034]    Thermal exchanger  112  may be triangular or sectoral in shape and includes an inlet port, an outlet port, one or more exchange channels fluidly connecting the inlet port to the outlet port, and typically a pair of sleeves adapted to slip onto the pair of arms  111  of the cooling assembly  110 . The pair of sleeves adapted to slip onto the pair of arms  111  are preferably positioned at or near the edges of thermal exchanger  112 . The inlet port and outlet port of thermal exchanger  112  may be permanently or removably secured to or integrated with the cooling channels  125  of the body  120 . Alternatively, the inlet port and outlet port may include a fitting or connector adapted to detachably engage the cooling channels  125  of the body  120 . Such fittings or connectors may be standard fluid fittings, such as Luer lock fittings, barbed fittings, or proprietary fittings. 
         [0035]    The one or more exchange channels of thermal exchanger  112  connect the inlet port to the outlet port, preferably without overlapping sections of exchange channel. For example, a single exchange channel may follow a generally zigzag or serpentine path from the inlet port to the outlet port without overlapping sections. A generally circular flow path may also be created without overlapping sections of channel. Alternatively, one or more sections of the one or more exchange channels may overlap within thermal exchanger  112 . The total cross-sectional area of the exchange channels of thermal exchanger  112  is preferably (A) constant along the length of the exchange channels and (B) equal to the cross-sectional area of one of the pair of axial cooling channels  125 . As the number of exchange channels increases, the cross-sectional area of each individual exchange channel may be decreased, keeping the total cross-section area of the one or more exchange channels constant. 
         [0036]    Cooling assembly  110  provides a flexible surface to facilitate heat transfer from the organ to the coolant. Thermal exchanger  112  typically folds and expands, accordion- or fan- like, as the pair of arms  111  move to the closed and open positions, respectively. Consequently, thermal exchanger  112  should be non-rigid, thermally conductive, and made from sufficiently strong material to withstand the pressure of the coolant circulating through surgical cooling device  100 . Generally, thermal exchanger  112  may be constructed of polymer film materials capable of handling the stress and pressure of the circulating coolant. Plastics, such as polyurethane film, are the preferred material for constructing thermal exchanger  112 . When polyurethane film is used, the one or more exchange channels of thermal exchanger  112  may be formed by radio-frequency welding two sheets of polyurethane in the desired exchange channel pattern. With respect to radio-frequency welding polyurethane sheets, although thermal exchanger  112  is initially empty, the one or more exchange channels will inflate with coolant as the coolant flows through the surgical cooling device  100 . To create a coolant-inflated exchange channel of approximately diameter D, the polyurethane film welds on the empty thermal exchanger  112  should be spaced approximately 1.57 D apart. An array of thermocouples may be embedded in or mounted on thermal exchanger  112  to measure the temperature distribution across all or part of thermal exchanger  112 . 
         [0037]    When surgical cooling device  100  is used, the pair of arms  111  are first moved to the open position shown in  FIG. 11 , and cooling assembly  110  is positioned on the organ to be cooled. The cooling assembly  110  may be opened and closed by manually grasping the pair of arms  111  and opening or closing the arms  111 . Coolant then flows into a first of the cooling channels  125 , through the inlet port of thermal exchanger  112 , through the one or more exchange channels of thermal exchanger  112 , through the outlet port of thermal exchanger  112 , and out a second of the cooling channels  125 . Thus, flow through thermal exchanger  112  is unidirectional. As the coolant flows through the one or more exchange channels, it absorbs heat from the organ. The coolant may be a fluid that is safe for use during surgery, such as water, ice slurry, cold air, ideal gas, or a saline solution. The coolant is circulated at a temperature and flow rate such that the organ temperature is able to drop to at least 10 degrees Celcius as the coolant flows through the thermal exchanger  112 . To measure the heat transfer, surgical cooling device  100  may include a pair of thermocouples embedded (as by insert molding) in the cooling channels  125  at or near the thermal exchanger  112 , preferably with one thermocouple in each cooling channel. The wires for the thermocouples may be routed through the cooling channels  125  or may be embedded in the body  120  of surgical cooling device  100 . 
         [0038]      FIG. 13  shows another view of surgical cooling device  100 . In surgical cooling device  200 , the handle  121  of body  120  includes a rubber grip  126  to provide a better hold. The rubber grip  126  may be smooth or textured. Referring to  FIG. 14 , surgical cooling device  200  includes a pair of torsional springs  127  at the joint between the pair of shoulders  123  and the pair of arms  111 . One purpose of torsional springs  127  is to aid in keeping the pair of arms  111  in the closed position when the surgical cooling device  200  is inserted or retracted. Thus, the pair of torsional springs  127  are oriented so as to exert a force on the pair of arms  111  toward the closed position. The torsional springs  127  are preferably of sufficient strength to force the pair of arms  111  into the closed position when the arms are unrestrained. 
         [0039]    To facilitate opening the pair of arms  111 , surgical cooling device  200  includes an opening mechanism, illustrated in  FIG. 15 ,  FIG. 16 , and  FIG. 17 . The opening mechanism comprises a pair of axial rod channels in body  120 , a pair of rods  128  positioned inside and slidable within the rod channels, and a control lever attached to the pair of rods  128 . Each rod  128  is adapted to engage a hemispherical indentation  114  on a wedge  115  on one of the pair of arms  111 . The wedge  115  on each of the pair of arms  111  protrudes inwardly toward the opposite arm. The hemispherical indentation  114  is adapted to receive a rod.  FIG. 16  shows the direction the pair of rods  128  move when opening the pair of arms  111 .  FIG. 17  shows another view of a rod  128  engaging a hemispherical indentation  114 . When the pair of arms  111  are in the open position, the arm control mechanism may be locked, for example with a cap and lock system (not shown in the Figures). Rubber grip  126  may be operable to lock the pair of arms  111  in an open position. 
         [0040]    While the subject of this specification has been described in connection with one or more exemplary embodiments, it is not intended to limit the claims to the particular forms set forth. On the contrary, the appended claims are intended to cover such alternatives, modifications and equivalents as may be included within their spirit and scope.