Therapeutic nonambient temperature fluid circulation system

A device is provided for therapeutically treating a desired region of a patient's body with a nonambient temperature fluid which is circulated through a pad having a tortuous fluid pathway which is positioned on the treatment region. The device has fluid inlet and outlet lines, each having an end connected to the pad and an opposite end positioned in a reservoir containing the nonambient temperature fluid, thereby providing fluid communication between the pad and the reservoir, and enabling continuous circulation of the fluid therebetween. Fluid drive is provided by a submersible pump at the end of the fluid inlet line in the reservoir. Temperature control of the pad is enabled by an in-line valve and temperature monitor positioned in the outlet line.

TECHNICAL FIELD 
The present invention relates generally to therapeutic treatment of the 
body. The present invention particularly relates to an apparatus for 
treating bodily injuries and ailments by cooling or heating the affected 
body surface. The present invention more particularly, though not 
exclusively, relates to an apparatus for continuously circulating a 
nonambient temperature fluid across a desired treatment surface of the 
body. 
BACKGROUND OF THE INVENTION 
Bodily injuries and ailments are commonly treated by applying a nonambient 
temperature material to the affected area of the body. For example, a low 
temperature material, typically applied in the form of ice or a cold 
liquid, advantageously inhibits swelling in the region of the injury. A 
high temperature material, typically applied in the form of hot water or 
an active heating element, advantageously reduces pain and promotes 
healing. A number of splint devices are known in the art for applying 
nonambient temperature materials to injured or otherwise ailing areas of 
the body as evidenced by U.S. Pat. Nos. 3,548,819 to Davis et al; 
3,901,225 to Sconce; and 4,706,658 to Cronin. One disadvantage of such 
devices is that the low temperature materials become warmer as they remain 
in contact with the body during treatment and the body transfers heat 
thereto. Conversely, high temperature materials become cooler as they 
transfer heat to the body. This disadvantage can be remedied by 
periodically replacing the nonambient temperature materials. However, 
constant replenishment of these materials is cumbersome and inconvenient, 
and results in periodic treatment temperature fluctuations. 
In response to this problem, a number of systems have been developed for 
continuously circulating a cooling fluid from a low temperature reservoir 
to a desired body location. Such systems are typified by U.S. Pat. Nos. 
2,726,658 to Chessey; 3,683,902 to Artemenko et al; and 4,962,761 to 
Golden. These systems are noteworthy in that they are relatively complex 
and thus, costly to manufacture and maintain, as well as being somewhat 
difficult to operate. Accordingly, the systems are not particularly 
practical for use among the general population. 
Given the proliferation of sports and leisure activities and the 
proliferation of injuries associated therewith, a widespread need exists 
for a practical therapeutic nonambient temperature treatment device. In 
particular, a need exists for a device which circulates a nonambient 
temperature fluid across a desired surface of the body to provide 
therapeutic treatment thereto, wherein the device is relatively simple to 
operate and inexpensive to produce and maintain. As such a therapeutic 
nonambient temperature treatment device is needed which can be employed in 
the home or in the workplace to provide cost-effective treatment which 
does not significantly disrupt the daily schedule of the user. 
SUMMARY OF THE INVENTION 
The present invention is a device for therapeutically treating a desired 
region of a patient's body with a nonambient temperature fluid, i.e., a 
cooling fluid or a heating fluid, which is circulated through a pad placed 
over the desired region. The pad encloses a continuous tortuous flowpath 
for the nonambient temperature fluid which has a fluid inlet port at its 
entrance and a fluid outlet port at its exit. Corresponding fluid inlet 
and outlet lines are provided, each having an end connected to the inlet 
and outlet ports respectively. The opposite ends of the fluid inlet and 
outlet lines are placed in a nonambient temperature reservoir containing 
an excess of nonambient temperature fluid, thereby providing fluid 
communication between the pad and the reservoir, and enabling circulation 
of the fluid therebetween. 
The end of the inlet line situated in the reservoir has a pump positioned 
thereon which is submersed in the fluid to provide a drive mechanism for 
the fluid. Thus, fluid circulation is effected by pumping the fluid from 
the reservoir through the inlet line into the pad via the inlet port. The 
fluid follows a tortuous flowpath through the pad to the outlet port where 
it is discharged back to the reservoir through the outlet line. 
To provide for temperature control of the pad, an in-line valve is 
positioned in either the inlet or outlet line, but preferably the outlet 
line. The valve is an adjustable flow restrictor, which enables regulation 
of the fluid flow rate through the system. In the case of a cooling fluid, 
by closing the valve to reduce the flow rate of fluid through the system, 
the fluid residence time in the pad increases, correspondingly increasing 
the temperature in the pad due to heat transfer effects from the body. By 
opening the valve to increase the flow rate, the cooling fluid residence 
time in the pad decreases causing a temperature decrease therein. 
Conversely, in the case of a heating fluid, closing the valve decreases 
the temperature in the pad, while opening the valve increases the 
temperature in the pad. An in-line temperature monitor is further 
provided, preferably in the outlet line, to enable operator monitoring of 
the fluid temperature in the pad. The in-line valve may accordingly be 
adjusted in response to temperature readings from the monitor. 
The temperature monitor and flow restriction valve may be enclosed within a 
unitary control housing. A manual valve control knob and a temperature 
display are operator accessible on the exterior of the housing. An 
electrical connector can also be provided on the exterior of the housing 
which is connected to an internal power line extending to the pump. The 
connector enables electrical connection of the pump to an external power 
source, such as a battery or a conventional wall outlet, via an external 
power line. Alternatively, the device may have its own internal power 
source in the form of a battery. 
A joint comprising a pair of inlet and outlet couplings is provided to 
connect the fluid inlet and outlet lines and the fluid inlet and outlet 
ports, respectively. The joint enables dissociation of the pad from the 
lines and allows interchangability or removal of the pad for storage or 
cleaning. An insulative sheath may be provided along the length of the 
inlet and outlet lines which, in association with the control housing, 
fully encloses the lines within a single tubular unit for ease of handling 
and for temperature insulation of the lines. The internal power line may 
further be included within the tubular unit extending from the housing to 
the pump. 
The device as described above is designed to be portable to the extent it 
is readily transportable for set up and use at varied locations. The 
nonambient temperature reservoir may be structurally dissociable from the 
remainder of the device so that it need not be transported with the device 
to each location of use, thereby enhancing the portability of the device. 
A conventional bucket or insulated passive cooler may be used as the 
reservoir, both of which are commonly available at most locations. One 
need only fill the reservoir with a nonambient fluid, such as ice water or 
hot water, and connect the power source to render the device operable. If 
the device is used for cooling and the reservoir becomes too warm, it can 
be restored to a low temperature simply by adding ice as desired. 
Likewise, if the device is used for heating and the reservoir becomes too 
cool, hot water can be added. 
The novel features of this invention, as well as the invention itself, both 
as to its structure and its operation, will be best understood from the 
accompanying drawings, taken in conjunction with the accompanying 
description, in which similar reference characters refer to similar parts, 
and in which:

DESCRIPTION OF PREFERRED EMBODIMENTS 
Referring initially to FIG. 1, the fluid circulation system of the present 
invention is shown and generally designated as 10. For purposes of 
illustration, FIG. shows a low temperature embodiment of the fluid 
circulation system of the present invention which is generally designated 
as 10. It is understood, however, that the description of system 10 as 
shown and set forth below applies generally to high temperature 
embodiments of the present invention as well. 
Referring to FIG. 1, system 10 comprises a cooling pad 12 positionable on 
the body of a patient at the point where therapeutic low temperature 
treatment is desired. Pad 12 is shown here on the arm 14, but it is 
apparent that pad 12 can be positioned substantially anywhere on the body 
where treatment is desired. Pad 12 is preferably fabricated from a pliable 
polyurethane film such that it is at least somewhat conformable to the 
body contours of the patient. To facilitate conformance, pad 12 has a 
plurality of seams 15 formed therein. 
Pad 12 has a fluid inlet port 16 and a fluid outlet port 18 which are 
connected to a fluid inlet line 20 and a fluid outlet line 22, 
respectively. Lines 20, 22 and ports 16, 18 have substantially the same 
inside diameter of about 3/16 inches and are connected at joint 24 having 
two snap-action locking couplings 26 and 28 having lock release buttons 27 
and 29. More specifically, fluid inlet port 16 is connected to the 
proximal end 20a of fluid inlet line 20 across inlet coupling 26, and 
fluid outlet port 18 is connected to the proximal end 22a of fluid outlet 
line 22 across outlet coupling 28. 
Each coupling 26, 28 comprises a male connector on the port side of the 
coupling and a female connector on the line side of the coupling. The male 
connectors of couplings 26, 28 are housed together in a unitary molded 
mount, and the female connectors are similarly housed in a unitary mount 
to facilitate simultaneous connection of couplings 26, 28. Couplings 26, 
28 are further provided with an internal shut off valve which 
automatically closes lines 20, 22 and ports 16, 18 when the couplings are 
disconnected. 
System 10 further comprises a pumping unit 30 and a control unit 32. 
Pumping unit 30 is connected to fluid inlet and outlet lines 20, 22 at 
distal ends 20b, 22b thereof. Control unit 32 is integral with lines 20, 
22, and has a housing 34 having a manually adjustable valve control knob 
36 and a temperature display 38 mounted thereon. Housing 34 also has an 
electrical connector 40 mounted thereon which enables an electrical 
connection between pumping unit 30 and an external power source. 
Specifically, electrical connection is provided by an external power line 
42 which is connected at one end to an internal power line 44 (shown in 
FIG. 3) across electrical connector 40 and which is connected at the other 
end to a conventional ac current wall plug 46 across a transformer 48. 
Internal power line 44 is positioned within a waterproof conduit 45 which 
extends from control unit 32 to pumping unit 30. 
System 10, as shown, is reliant on an external ac current power source 
which limits its portability. As an alternate external power source to 
conventional ac current, a portable external battery pack (not shown) may 
be provided consisting of disposable dry D-cell batteries or rechargeable 
batteries. External power for system 10 may also be obtained from an 
automobile battery by providing an adaptor line (not shown) from connector 
40 which fits into an automobile cigarette lighter outlet. 
System 10 may be rendered more portable by eliminating electrical connector 
40 external power cord 42, and transformer 48 and replacing them with an 
internal power pack (not shown) in control unit 32 which is connected to 
internal power line 44. Alternatively, electrical connector 40, external 
power cord 42, and transformer 48 may be retained in parallel with an 
internal power pack to provide system 10 with the capability of utilizing 
either an external or internal power source. 
An insulative sheath 50 is provided over cooling fluid inlet and outlet 
lines 20, 22 and conduit 45 which, in conjunction with control unit 
housing 32, forms a substantially water-proof tubular unit 52 containing 
lines 20, 22 and conduit 45 from junction 24 to pump unit 30. Sheath 50 as 
well as lines 20, 22 and conduit 45 are formed from flexible materials 
which render tubular unit 52 fully flexible. Sheath 50 has a strong and 
resilient plastic exterior skin and an insulating foam interior which 
minimizes heat exchange between lines 20, 22 and the ambient atmosphere 
and further prevents condensate formation on the exterior of lines 20, 22. 
A flexible sheath 54 having a similar composition may also be provided 
over inlet and outlet ports 16, 18 extending between junction 24 and pad 
12 to form a tubular unit 56 for ports 16, 18. 
System 10 has a low temperature reservoir 58 which as shown is structurally 
independent of the remainder of system 10 such that pump unit 30 and 
distal ends 20b, 22b of lines 20a, 22a are freely positionable within 
reservoir 58. Alternatively, reservoir 58 can be structurally integral 
with system 10 by connecting line 20, 22 thereto. Reservoir 58 may be 
substantially any externally-accessible hollow fluid container, such as a 
bucket or a tub, although it is preferably an insulated container, such as 
a conventional insulated picnic cooler having a cover (not shown) for 
maintaining the low temperature therein. Cooling fluid 60, which is a 
fluid cooled below ambient room temperature and preferably ice water, is 
retained within reservoir 58. 
FIG. 2 shows the interior baffle pattern of cooling pad 12, wherein the 
polyurethane outer shell of pad 12 has been removed for purposes of 
illustration. Pad 12 contains a plurality of baffles 62 which are arranged 
to provide a tortuous flowpath 64 for cooling fluid 60 entering pad 12 via 
inlet port 16, and exiting pad 12 via outlet port 18. It is noted that 
baffles 62 engage the outer shell of pad 12 both at their tops and bottoms 
to prevent short-circuiting of baffles 62, thereby forcing cooling fluid 
60 to flow around baffles 62 in a tortuous manner. 
FIG. 3 shows pump unit 30 in detail. Pump unit 30 comprises a pump housing 
66 having a top portion 66a and a bottom portion 66b which are held 
together by screws 68 fitting into screw holes 70. Top housing portion 66a 
has a pump inlet port 72 which is perforated to allow fresh cooling fluid 
60 to pass therethrough from reservoir 58, while blocking large solid 
particles, such as crushed ice, from passing therethrough. Top housing 
portion 66a also has an opening 74 formed therein to receive tubular unit 
52 containing inlet and outlet lines 20, 22 and conduit 45. Bottom housing 
portion 66b has a pump outlet port 76 which receives cooling fluid from 
pad 12 via outlet line 22 and discharges it to reservoir 58. 
Internal to housing 66 are upper plate 78a and lower plate 78b. Upper plate 
78a has a nozzle so formed therein which provides fluid communication 
between distal end of inlet line 20b and pumping chamber 82. The space 
between plates 78a and 78b define chamber 82. Upper plate 78a also has a 
cooling fluid inlet passageway 84, outlet line opening 86, and power line 
opening 88 formed therethrough. Lower plate 78b has a nozzle 90 formed 
therein which provides fluid communication between distal end of outlet 
line 22b and pump outlet port 76. Lower plate 78b is further provided with 
a nipple 92 through which line 45 passes to pump motor 94 disposed within 
bottom housing portion 66b. Lower plate 78b is water-tight to prevent 
intrusion of water into motor 94. Pump motor 94 has a drive shaft 96 
extending into pumping chamber 82 via shaft opening 98 formed through 
lower plate 78b. Shaft 96 connects to an impeller blade 100 disposed 
within chamber 82. 
METHOD OF OPERATION 
The fluid circulation system 10 of the present invention is operated by 
filling low temperature reservoir 58 with ice water 60, which is at a 
temperature approaching the freezing point of water, and covering 
reservoir 58 to maintain the fluid temperature therein. With joint 24 
secured, pad 12 is placed on the skin of the patient at the point on the 
body where therapeutic treatment is desired. An additional padding 
material, such as a soft cloth, may be placed on the skin between the 
pliable surface of pad 12 and the skin for the comfort of the patient. 
Pump unit 30 is submerged in the ice water 60 and external power line 42 is 
connected to a power source to activate the pump motor 94. Fresh ice water 
60 is drawn from reservoir 58 into pumping chamber 82 and driven by 
impeller blade 100 through inlet line 20 and inlet port 16 into pad 12. 
The ice water travels the entirety of flowpath 64 and exits pad 12 via 
outlet port 18. The ice water is returned to reservoir 58 via outlet line 
22 and pump outlet port 76. 
This fluid circulation cycle is performed continuously for the duration of 
the desired treatment period. Temperature control of pad 12 during the 
circulation cycle is achieved by manually adjusting a conventional flow 
restrictor valve, which is preferably integral with control unit 32 and 
positioned across outlet line 22. The valve is adjusted by means of valve 
control knob 36 on control unit 32. By turning knob 36 in a direction to 
restrict flow through line 22, the temperature of pad 12 is increased, and 
conversely by turning knob 36 in the opposite direction to increase flow 
through line 22, the temperature of pad 12 is decreased. If the ice in 
reservoir 58 becomes depleted, additional amounts of ice may be added as 
needed. The valve of control unit 32 further acts to regulate the back 
pressure in system 10 as a function of the size of the valve opening. 
Temperature control is facilitated by the temperature display 38 on the 
control unit 32 which is in communication with a temperature measuring 
means. The temperature measuring means and display 38 are preferably 
provided in the form of a conventional liquid thermometer which is 
positioned in outlet line 22. Termination of the circulation cycle is 
enabled simply by disconnecting the external power line 42 from the power 
source. 
The high temperature embodiment of system 10 is primarily distinguishable 
from the low temperature embodiment described above in that a heated fluid 
is substituted for the cooling fluid. The heated fluid is preferably water 
which is heated to a temperature above room temperature, i.e., exceeding 
ambient. The temperature of the pad containing the heated fluid may be 
decreased by partially closing the valve across the outlet line to 
diminish flow therethrough, while the temperature of the pad may be 
increased by opening the valve to increase the flow. 
While the particular Therapeutic Nonambient Temperature Fluid Circulation 
System as herein shown and disclosed in detail is fully capable of 
obtaining the objects and providing the advantages herein before stated, 
it is to be understood that it is merely illustrative of the presently 
preferred embodiments of the invention and that no limitations are 
intended to the details of construction or design herein shown other than 
as described in the appended claims.