US3853479A - Blood oxygenating device with heat exchanger - Google Patents

Blood oxygenating device with heat exchanger Download PDF

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US3853479A
US3853479A US00265864A US26586472A US3853479A US 3853479 A US3853479 A US 3853479A US 00265864 A US00265864 A US 00265864A US 26586472 A US26586472 A US 26586472A US 3853479 A US3853479 A US 3853479A
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blood
chamber
plates
reservoir chamber
combination according
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US00265864A
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D Talonn
D Cooley
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Sherwood Medical Co
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Sherwood Medical Industries Inc
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Priority to US00265864A priority Critical patent/US3853479A/en
Priority to GB2219773A priority patent/GB1398818A/en
Priority to DE2324545A priority patent/DE2324545A1/en
Priority to JP48057644A priority patent/JPS4943492A/ja
Priority to BE131593A priority patent/BE800124A/en
Priority to FR7321765A priority patent/FR2189079B1/fr
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Assigned to SHERWOOD MEDICAL COMPANY reassignment SHERWOOD MEDICAL COMPANY MERGER (SEE DOCUMENT FOR DETAILS). Assignors: SHERWOOD MEDICAL INDUSTRIES INC. (INTO)
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    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61MDEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
    • A61M5/00Devices for bringing media into the body in a subcutaneous, intra-vascular or intramuscular way; Accessories therefor, e.g. filling or cleaning devices, arm-rests
    • A61M5/44Devices for bringing media into the body in a subcutaneous, intra-vascular or intramuscular way; Accessories therefor, e.g. filling or cleaning devices, arm-rests having means for cooling or heating the devices or media
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61MDEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
    • A61M2205/00General characteristics of the apparatus
    • A61M2205/36General characteristics of the apparatus related to heating or cooling
    • A61M2205/366General characteristics of the apparatus related to heating or cooling by liquid heat exchangers
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S128/00Surgery
    • Y10S128/03Heart-lung
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S261/00Gas and liquid contact apparatus
    • Y10S261/28Blood oxygenators

Definitions

  • ABSTRACT A blood oxygenation device with a heat exchanger that includes a pair of plates disposed against the opposite sides of a flexible blood containing chamber of v 9 Claims, 5 Drawing Figures l'EMl CONTROL PATENTEMCI 01974 sum 1 nr 2 TEMP CONTROL FIG. 1 1 52 1 25 5 72 I "I 75 FIG. .3 g
  • This invention relates to blood oxygenation apparatus and more particularly to an improved temperature control device for an oxygenation device.
  • Blood oxygenation devices are generally provided with blood temperature control devices which may include heat exchangers interposed in series in the extracorporeal circulating system.
  • Various types of heat exchange devices have been proposed, however, they have not been entirely satisfactory for one reason or another.
  • Some heat exchangers result in an increase in extracorporeal blood volume due to the blood priming requirement of the exchanger, and an increase in the length of the blood flow path thereby increasing the danger of damage to the bood. With some devices there exists the danger that, should any heat exchange fluid leak from the exchanger, the blood would be subjected to contamination by such fluid.
  • Some proposed devices are lacking in other aspects such as heat transfer efficiency, and high cost.
  • the blood volume or capacity of the oxygenation device in order to alter the priming volume of blood, for example, to minimize the priming volume for given patients. It is also desirable or necessary to maintain the blood in the reservoir chamber of an oxygenation device at its designed normal operating level so that the device functions in a manner consistent with its designed characteristics. While the blood capacity or level in the reservoir chamber can be varied by pinching off a portion of the chamber, such a method is not satisfactory because it affects the normal blood flow path through the device which may damage the blood, and it is an inaccurate way to vary the capacity.
  • Another object is to provide an improved blood oxygenation device and blood temperature control in which the priming volume of blood may be readily and accurately varied and the temperature of the blooc efficiently controlled.
  • Another object is to provide a novel heat exchanger in combination with a blood oxygenation device which is highly efficient in operation to either heat or cool the blood, and which is capable of varying the bood capacity of the oxygenation device.
  • Another object is to provide a novel blood oxygenation device having a blood reservoir compartment of plastic material, and a heat exchange device which provides efficient heat transfer characteristics, is capable of adjusting the blood level, and wherein the danger of blood contamination from the heat exchanger device is eliminated.
  • Still another object is to provide improved blood oxygenation apparatus having a disposable blood oxygenation device with a reusable heat exchanger wherein blood does not come in contact with the heat exchanger and the danger of cross-infection is eliminated.
  • blood oxygenation apparatus which includes a compartment for containing blood, and a heat exchanger disposed in contact with the exterior of the blood compartment.
  • the heat exchanger includes a pair of plates positioned respectively on opposite sides of a flexible blood compartment and are relatively movable to vary the volume of the compartment and effect heat transfer therewith.
  • FIG. 1 is an elevational view of an oxygenation device and a blood temperature control in accordance with a preferred embodiment of the present invention
  • FIG. 2 is a cross-sectional view taken along the line 22 of FIG. 1;
  • FIG. 3 is a cross-sectional view taken along the line 3--3 of FIG. 1;
  • FIG. 4 is a perspective view of the heat exchanger of FIG. 1;
  • FIG. 5 is a perspective view of a modified form of heat exchanger.
  • FIG. 1 blood oxygenation apparatus including an oxygenation device 10 supported by a frame 12 connected to a standard 14, and a temperature control device, indicated generally at 16, which is also supported by the standard 14.
  • the device 10 is shown connected to frame 12 by a plurality of supporting rings 15.
  • Oxygenation device 10 is of the plastic bag type which is generally formed by uniting a pair of supple plastic sheets 17 and 18, such as by predeterminately located heat seals, to form a number of chambers or compartments such as a defoaming compartment 20, and a settling reservoir compartment or chamber 22.
  • An oxygenator 24 is connected at the upper end thereof to the defoaming chamber 20.
  • Oxygenator 24 is similar to the oxygenator shown and described in copending application S'er. No. 263,049, filed June 15, 1972, by N. W. Burlis and assigned to the same assignee as this application and now, US. Pat. No. 3,827,860, issued Aug. 8, I974.
  • Oxygenator 24 includes a hollow member 26 having interior walls forming an oxygenator column or chamber 27 which receives a movable oxygenating gas disperser and venous blood delivery member 28 shown in phantom in FIG. 1 and described in detail in the above copending application.
  • the member 28 is provided with three tubes 29, 30 and 31, two of which, such as tubes 29 and 30, may be connected to a source of venous blood while the tube 31 is connected to a source of oxygenating gas.
  • the member 26 is cylindrical and may be of plastic material and formed by cutting it to size from plastic tubing. Member 26 is connected, such as by heat sealing, to the interior of the defoaming chamber 20.
  • the disperser member 28 is provided with an upper plate and a plurality of small holes for dispersing gas into the blood in the chamber 27. It also has connections for connecting the tubes 29 and 30 through the member 28 to pass blood into chamber 27, the blood flowing over the plate with the holes and being subjected to the gas bubbles, as described in the above mentioned copending application.
  • a releasable clamp 32 is shown clamping the movable member 28 in a desired location in member 26 in sealing engagement with the walls of the chamber 27.
  • the member 28 is movable after releasing clamp 32, by pulling on the tubes 29, 30 and 31 or by working the member externally through the tube 26 where the tube 26 is sufficiently supple, or a plunger rod (not shown) may be used to engage and connect with the member 28 to move it in one or both directions within the chamber 27 as desired.
  • the oxygenator 24 can be selectively adjusted to subject the venous blood to oxygenating gas for different lengths of time so that the same oxygenation device can be used to efficiently oxygenate venous blood for different flow rates and for patients of various sizes.
  • venous blood flows in tubes 29 and/or 30 into the oxygenator chamber 27, and oxygenating gas bubbles through the blood generating a blood foam which moves upwardly into defoaming chamber 20.
  • An antifoam member 40 such as formed of plastic or metal fihers, is shown in phantom disposed in the defoaming chamber and extending into the settling reservoir chamber 22 below the designed blood level, indicated at 39 in FIG. 1.
  • the defoaming member 40 may be enclosed in a filter (not shown) such as a nylon woven stockinglike member.
  • the blood temperature control device 16 includes a heat exchanger 50 including front and rear heat exchange members 52 and 54 that engage the external sides of settling reservoir chamber 22 of device 10.
  • the members 52 and 54 as also seen in FIG. 2, are shown as hollow plates, for example, of stainless steel, having heat transfer fluid inlet conduits 56 and 58 connected to a suitable fluid temperature control device 60, and a pair of outlet conduits 62 and 64 for discharging fluid from within the members 52 and 54 for returning it to the heat exchange system.
  • the heat exchange members 52 and 54 are hinged together for pivotal movement relative to each other such as by hinges 70 and 72 connected to a vertical supporting member 74 of the standard 14.
  • the heat exchange members may be opened or moved away from each other, such as shown in FIG. 4, to allow insertion of the oxygenation device 10.
  • heat exchange members 52 and 54 are shown mounted for adjusting movement relative to each other by connecting the hinges 70 and 72 for movement relative to the supporting member 74 by rivets 75 and 76 slidable in slots 77 and 78 in member 74.
  • the space between the members 52 and 54 is accurately adjustedby a pair of threaded adjusting screws 80 and 81 provided with handles.
  • the screws 80 and 81 are shown connected for rotation on member 52 and threadedly coupled to the member 54.
  • the heat exchange members 52 and 54 are shown in FIG. 2 engaging the external, opposed sides of the blood reservoir compartment 22 for effecting a rela tively narrow reservoir chamber main portion 22a therebetween which connects at its upper end with a relatively wide, shallow reservoir chamber portion 22b at the top. It will be apparent that by varying the distance between the heat exchange members 52 and 54 by means of screws and 81, the shape and volume of the reservoir chamber portion 220 can be varied and the total capacity of the chamber 22 changed. Also, the heat exchange members 52 and 54 intimately engage opposed sides of chamber 22 and, since chamber 22 is resilient or supple, compress and cause the chamber walls to conform in shape to the shape of the facing sides of the heat exchange members to maximize the areas of contact between the chamber of blood and heat exchange members for efficient heat transfer.
  • the facing surfaces of the heat exchange members in the illustrated embodiment are planar and parallel to each other and contact the entire surface area of chamber portion 22a which constitutes the major surface area of the chamber 22.
  • the temperature control device 16 may employ a liquid, such as water, flowing into the inlet tubes 56 and 58 and out the outlet tubes 62 and 64 to control the temperature of the heat exchange members.
  • the temperature of the water is controlled by any suitable temperature monitoring and control means well known in the art to either heat or cool the water.
  • Each of the heat exchange members 52 and 54 may be provided with internal baffling such as indicated at 79 and 79' in FIG. 2.
  • the cooling or heating liquid flowing in the heat exchanger system may be used to cool or heat the blood as desired or required, and with the blood containing chamber 22 and heat exchanger disposed in the atmosphere of the operating room where they may be continuously viewed.
  • a pair of turn counters 82 and 83 are shown connected to heat exchange member 52 respectively adjacent the screws 80 and 81.
  • the counters may be of the well known tumbler type and geared to the screws to provide an indication of the number of turns that the screws have been rotated and the relative positions or spacing of the members 52 and 54.
  • the counters By correlating the turns with the spacing between the members and the volume of the portions of reservoir chamber 22, the counters give an accurate indication of the volume or blood capacity of the chamber 22 for any given setting of the screws 80 and 81.
  • the volume of the chamber 22 is readily adjusted to a desired value and can be readjusted or reset accurately by use of counters 82 and 83 which serve as volume indicating devices.
  • Heat exchanger 84 includes a rear hollow heat exchange plate member 85 connected,
  • Member 85 has fluid inlet and outlet tubes 87 and 87 for controlling the temperature of member 85.
  • a front plate member or panel 86 is hinged to support 74' or to member 85 if desired.
  • the members 85 and 86 are relatively movable toward and away from each other by means such as the sliding hinge shown and a pair of threaded adjustment screws 88 and 89.
  • the panel or front plate member 86 is formed of a transparent material such as glass or plastic, for the purpose of permitting the technician or surgeon to visually observe substantially the total blood flow in the oxygenation device, such as device 10, that is to be inserted between members 84 and 85 during use.
  • the heat exchanger 84 is capable of varying the blood carrying capacity of a supple or resilient plastic compartment, such as a settling reservoir chamber 22, in the same manner as described herein in connection with the heat exchanger 50 of FIG. 1.
  • the chamber to be disposed between members 85 and 86, such as the supple chamber 22 of oxygenation device 10, has its facing sides conform to the surfaces of these members. In this illustrated arrangement, only member 85 is connected to a source of heat transfer fluid.
  • a blood oxygenation device including an oxygenator chamber, means for introducing venous blood and oxygenation gas to said oxygenator chamber for producing gas bubbles in the blood to oxygenate the blood, a defoaming chamber connected to receive blood from said oxygenator chamber and having anti-foam means therein for assisting in the removal of excess gas and vent means for venting excess gas to atmosphere, and a supple plastic blood settling reservoir chamber connected to receive blood from said defoaming chamber, said reservoir chamber having an outlet for discharging oxygenated blood, and blood temperature control means including a heat exchanger having a pair of relatively movable plates disposed respectively on opposite sides of said reservoir chamber, adjustment means for adjustably effecting relative movement between said plates to clamp at least a portion of said reservoir chamber therebetween to selectively vary the volume of said reservoir chamber, and means for varying the temperature of at least one of said plates to control the temperature of the blood.
  • said adjustment means includes indicia to indicate the relative positions of said plates.

Abstract

A blood oxygenation device with a heat exchanger that includes a pair of plates disposed against the opposite sides of a flexible blood containing chamber of the device. The plates are relatively movable to selectively vary the volume of the chamber and the blood priming volume of the device. One or both of the plates are used as a heat exchange member to raise or lower the temperature of the blood flowing in the oxygenation device.

Description

United States Patent Talonn et a1.
[ BLOOD OXYGENATING DEVICE WITH HEAT EXCHANGER [75] Inventors: Daniel A. Talonn, University City,
Mo.; Denton A. Cooley, Houston, Tex.
[73] Assignee: Sherwood Medical Industries, Inc.,
St. Louis, Mo.
[22] Filed: June 23, 1972 [21] Appl. No.1 265,864
[52] U.S. Cl 23/258.5, 128/DIG. 3, 165/46, 261/D1G. 28 [51] Int. Cl A61m 1/03 [58] Field of Search 23/258.5; l28/DIG. 3; 261/DIG. 28; 165/46; 195/1.8
[56] References Cited UNITED STATES PATENTS 2,934,067 4/1960 Calvin 23/258.5 3,207,156 9/1965 Lerman.... 23/258.5 3,291,568 12/1966 Sautter 23/258.5 3,332,746 7/1967 Claff et al.... 23/258.5 3,374,066 3/1968 Farrant 23/258.5
[ Dec. 10, 1974 3,493,347 2/1970 Everett 1 23/25 8.5 3,578,411 5/1971 Bentley et al..... 23/258.5
3,729,377 4/1973 Leonard .1 23/258.5 R27,l00 3/1971 DeWall 23/258.5
OTHER PUBLICATIONS Galletti et al., Temperature Regulating Devices and Heat Exchangers, Heart-Lung By-Pass; 2nd Printing; 2/66; Grune & Stratton; pp. 164-170.
Primary ExaminerBarry S. Richman Attorney, Agent, or FirmStan1ey N. Garber; William R. OMeara [5 7] ABSTRACT A blood oxygenation device with a heat exchanger that includes a pair of plates disposed against the opposite sides of a flexible blood containing chamber of v 9 Claims, 5 Drawing Figures l'EMl CONTROL PATENTEMCI 01974 sum 1 nr 2 TEMP CONTROL FIG. 1 1 52 1 25 5 72 I "I 75 FIG. .3 g
I l 'I/l/l/ /II. /7 Z i 1 7p BLOOD OXYGENATING DEVICE WITH IEAT EXCHANGER BACKGROUND OF THE INVENTION This invention relates to blood oxygenation apparatus and more particularly to an improved temperature control device for an oxygenation device.
Blood oxygenation devices are generally provided with blood temperature control devices which may include heat exchangers interposed in series in the extracorporeal circulating system. Various types of heat exchange devices have been proposed, however, they have not been entirely satisfactory for one reason or another. Some heat exchangers, for example, result in an increase in extracorporeal blood volume due to the blood priming requirement of the exchanger, and an increase in the length of the blood flow path thereby increasing the danger of damage to the bood. With some devices there exists the danger that, should any heat exchange fluid leak from the exchanger, the blood would be subjected to contamination by such fluid. Some proposed devices are lacking in other aspects such as heat transfer efficiency, and high cost.
In some cases, it is desired to change the blood volume or capacity of the oxygenation device in order to alter the priming volume of blood, for example, to minimize the priming volume for given patients. It is also desirable or necessary to maintain the blood in the reservoir chamber of an oxygenation device at its designed normal operating level so that the device functions in a manner consistent with its designed characteristics. While the blood capacity or level in the reservoir chamber can be varied by pinching off a portion of the chamber, such a method is not satisfactory because it affects the normal blood flow path through the device which may damage the blood, and it is an inaccurate way to vary the capacity.
SUMMARY OF THE PRESENT INVENTION It is therefore an object of the present invention to provide an improved blood oxygenation device with a blood temperature control wherein the abovementioned disadvantages are substantially obviated.
Another object is to provide an improved blood oxygenation device and blood temperature control in which the priming volume of blood may be readily and accurately varied and the temperature of the blooc efficiently controlled.
Another object is to provide a novel heat exchanger in combination with a blood oxygenation device which is highly efficient in operation to either heat or cool the blood, and which is capable of varying the bood capacity of the oxygenation device.
Another object is to provide a novel blood oxygenation device having a blood reservoir compartment of plastic material, and a heat exchange device which provides efficient heat transfer characteristics, is capable of adjusting the blood level, and wherein the danger of blood contamination from the heat exchanger device is eliminated.
Still another object is to provide improved blood oxygenation apparatus having a disposable blood oxygenation device with a reusable heat exchanger wherein blood does not come in contact with the heat exchanger and the danger of cross-infection is eliminated.
In accordance with one form of the present invention, blood oxygenation apparatus is provided which includes a compartment for containing blood, and a heat exchanger disposed in contact with the exterior of the blood compartment. In accordance with another aspect, the heat exchanger includes a pair of plates positioned respectively on opposite sides of a flexible blood compartment and are relatively movable to vary the volume of the compartment and effect heat transfer therewith.
These and other objects and advantages of the present invention will be apparent from the following de-" tailed description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view of an oxygenation device and a blood temperature control in accordance with a preferred embodiment of the present invention;
FIG. 2 is a cross-sectional view taken along the line 22 of FIG. 1;
FIG. 3 is a cross-sectional view taken along the line 3--3 of FIG. 1;
FIG. 4 is a perspective view of the heat exchanger of FIG. 1; and
FIG. 5 is a perspective view of a modified form of heat exchanger.
DESCRIPTION OF THE PREFERRED. EMBODIMENT Referring now to the drawings, and particularly to FIG. 1, there is shown blood oxygenation apparatus including an oxygenation device 10 supported by a frame 12 connected to a standard 14, and a temperature control device, indicated generally at 16, which is also supported by the standard 14. The device 10 is shown connected to frame 12 by a plurality of supporting rings 15.
Oxygenation device 10 is of the plastic bag type which is generally formed by uniting a pair of supple plastic sheets 17 and 18, such as by predeterminately located heat seals, to form a number of chambers or compartments such as a defoaming compartment 20, and a settling reservoir compartment or chamber 22. An oxygenator 24 is connected at the upper end thereof to the defoaming chamber 20. Oxygenator 24 is similar to the oxygenator shown and described in copending application S'er. No. 263,049, filed June 15, 1972, by N. W. Burlis and assigned to the same assignee as this application and now, US. Pat. No. 3,827,860, issued Aug. 8, I974.
Oxygenator 24 includes a hollow member 26 having interior walls forming an oxygenator column or chamber 27 which receives a movable oxygenating gas disperser and venous blood delivery member 28 shown in phantom in FIG. 1 and described in detail in the above copending application. The member 28 is provided with three tubes 29, 30 and 31, two of which, such as tubes 29 and 30, may be connected to a source of venous blood while the tube 31 is connected to a source of oxygenating gas. The member 26 is cylindrical and may be of plastic material and formed by cutting it to size from plastic tubing. Member 26 is connected, such as by heat sealing, to the interior of the defoaming chamber 20. The disperser member 28 is provided with an upper plate and a plurality of small holes for dispersing gas into the blood in the chamber 27. It also has connections for connecting the tubes 29 and 30 through the member 28 to pass blood into chamber 27, the blood flowing over the plate with the holes and being subjected to the gas bubbles, as described in the above mentioned copending application. A releasable clamp 32 is shown clamping the movable member 28 in a desired location in member 26 in sealing engagement with the walls of the chamber 27. The member 28 ,is movable after releasing clamp 32, by pulling on the tubes 29, 30 and 31 or by working the member externally through the tube 26 where the tube 26 is sufficiently supple, or a plunger rod (not shown) may be used to engage and connect with the member 28 to move it in one or both directions within the chamber 27 as desired. In this way the oxygenator 24 can be selectively adjusted to subject the venous blood to oxygenating gas for different lengths of time so that the same oxygenation device can be used to efficiently oxygenate venous blood for different flow rates and for patients of various sizes.
When the oxygenation device is connected for operation and provided with a suitable amount of priming blood, venous blood flows in tubes 29 and/or 30 into the oxygenator chamber 27, and oxygenating gas bubbles through the blood generating a blood foam which moves upwardly into defoaming chamber 20. An antifoam member 40, such as formed of plastic or metal fihers, is shown in phantom disposed in the defoaming chamber and extending into the settling reservoir chamber 22 below the designed blood level, indicated at 39 in FIG. 1. The defoaming member 40 may be enclosed in a filter (not shown) such as a nylon woven stockinglike member. Blood flows into the settling chamber 22 with the excess oxygen gas and carbon dioxide leaving the defoaming chamber and settling chamber and passing to atmosphere by way of a vent indicated at 42. The oxygenated blood flows through an outlet 44 at the bottom of chamber 22, and, by means of a pump, into the arterial system of the patient to which it is connected.
The blood temperature control device 16 includes a heat exchanger 50 including front and rear heat exchange members 52 and 54 that engage the external sides of settling reservoir chamber 22 of device 10. The members 52 and 54, as also seen in FIG. 2, are shown as hollow plates, for example, of stainless steel, having heat transfer fluid inlet conduits 56 and 58 connected to a suitable fluid temperature control device 60, and a pair of outlet conduits 62 and 64 for discharging fluid from within the members 52 and 54 for returning it to the heat exchange system. The heat exchange members 52 and 54 are hinged together for pivotal movement relative to each other such as by hinges 70 and 72 connected to a vertical supporting member 74 of the standard 14. The heat exchange members may be opened or moved away from each other, such as shown in FIG. 4, to allow insertion of the oxygenation device 10.
As seen more fully in FIGS. 3 and 4, heat exchange members 52 and 54 are shown mounted for adjusting movement relative to each other by connecting the hinges 70 and 72 for movement relative to the supporting member 74 by rivets 75 and 76 slidable in slots 77 and 78 in member 74. The space between the members 52 and 54 is accurately adjustedby a pair of threaded adjusting screws 80 and 81 provided with handles. The screws 80 and 81 are shown connected for rotation on member 52 and threadedly coupled to the member 54.
The heat exchange members 52 and 54 are shown in FIG. 2 engaging the external, opposed sides of the blood reservoir compartment 22 for effecting a rela tively narrow reservoir chamber main portion 22a therebetween which connects at its upper end with a relatively wide, shallow reservoir chamber portion 22b at the top. It will be apparent that by varying the distance between the heat exchange members 52 and 54 by means of screws and 81, the shape and volume of the reservoir chamber portion 220 can be varied and the total capacity of the chamber 22 changed. Also, the heat exchange members 52 and 54 intimately engage opposed sides of chamber 22 and, since chamber 22 is resilient or supple, compress and cause the chamber walls to conform in shape to the shape of the facing sides of the heat exchange members to maximize the areas of contact between the chamber of blood and heat exchange members for efficient heat transfer. The facing surfaces of the heat exchange members in the illustrated embodiment are planar and parallel to each other and contact the entire surface area of chamber portion 22a which constitutes the major surface area of the chamber 22.
While the temperature of the plates 52 and 54 may be varied by various means other than fluids, for example, electronically, the temperature control device 16 may employ a liquid, such as water, flowing into the inlet tubes 56 and 58 and out the outlet tubes 62 and 64 to control the temperature of the heat exchange members. The temperature of the water is controlled by any suitable temperature monitoring and control means well known in the art to either heat or cool the water. Each of the heat exchange members 52 and 54 may be provided with internal baffling such as indicated at 79 and 79' in FIG. 2. The cooling or heating liquid flowing in the heat exchanger system may be used to cool or heat the blood as desired or required, and with the blood containing chamber 22 and heat exchanger disposed in the atmosphere of the operating room where they may be continuously viewed.
Because of the relatively shallow, relatively wide upper chamber portion 22b as a result of the clamping forces applied by the heat exchanger 50, bubbles entering this portion readily rise and pass upwardly and out vent 42 to atmosphere, the relatively large surface of blood in portion 22b providing an efficient pool for the escape of such bubbles.
A pair of turn counters 82 and 83 are shown connected to heat exchange member 52 respectively adjacent the screws 80 and 81. The counters may be of the well known tumbler type and geared to the screws to provide an indication of the number of turns that the screws have been rotated and the relative positions or spacing of the members 52 and 54. By correlating the turns with the spacing between the members and the volume of the portions of reservoir chamber 22, the counters give an accurate indication of the volume or blood capacity of the chamber 22 for any given setting of the screws 80 and 81. Thus, the volume of the chamber 22 is readily adjusted to a desired value and can be readjusted or reset accurately by use of counters 82 and 83 which serve as volume indicating devices.
In FIG. 5, there is shown a modification of the heat exchanger at 84. Heat exchanger 84 includes a rear hollow heat exchange plate member 85 connected,
such as by screws (not shown), to a vertical support 74'. Member 85 has fluid inlet and outlet tubes 87 and 87 for controlling the temperature of member 85. A front plate member or panel 86 is hinged to support 74' or to member 85 if desired. The members 85 and 86 are relatively movable toward and away from each other by means such as the sliding hinge shown and a pair of threaded adjustment screws 88 and 89. In this case, the panel or front plate member 86 is formed of a transparent material such as glass or plastic, for the purpose of permitting the technician or surgeon to visually observe substantially the total blood flow in the oxygenation device, such as device 10, that is to be inserted between members 84 and 85 during use. For example, it may be desirable to continuously observe the blood in the reservoir chamber, such as reservoir chamber 22 of device 10, during surgery to ensure against the flow of a hubble into the outlet 44. The heat exchanger 84 is capable of varying the blood carrying capacity of a supple or resilient plastic compartment, such as a settling reservoir chamber 22, in the same manner as described herein in connection with the heat exchanger 50 of FIG. 1. The chamber to be disposed between members 85 and 86, such as the supple chamber 22 of oxygenation device 10, has its facing sides conform to the surfaces of these members. In this illustrated arrangement, only member 85 is connected to a source of heat transfer fluid.
It will now be apparent that all of the objects and advantages of the present invention hereinbefore mentioned, as well as others, are provided by the present invention. lt should be understood that although this invention has been described with reference to the illustrated preferred embodiments, modifications thereto may be made without departing from the true spirit and scope of the invention.
What is claimed is:
1. In combination, a blood oxygenation device including an oxygenator chamber, means for introducing venous blood and oxygenation gas to said oxygenator chamber for producing gas bubbles in the blood to oxygenate the blood, a defoaming chamber connected to receive blood from said oxygenator chamber and having anti-foam means therein for assisting in the removal of excess gas and vent means for venting excess gas to atmosphere, and a supple plastic blood settling reservoir chamber connected to receive blood from said defoaming chamber, said reservoir chamber having an outlet for discharging oxygenated blood, and blood temperature control means including a heat exchanger having a pair of relatively movable plates disposed respectively on opposite sides of said reservoir chamber, adjustment means for adjustably effecting relative movement between said plates to clamp at least a portion of said reservoir chamber therebetween to selectively vary the volume of said reservoir chamber, and means for varying the temperature of at least one of said plates to control the temperature of the blood.
2. The combination according to claim 1 wherein said adjustment means includes indicia to indicate the relative positions of said plates.
3. The combination according to claim 1 wherein said reservoir chamber and the other of said plates are transparent.
4. The combination according to claim 1 wherein said reservoir chamber portion comprises the major surface area of said reservoir chamber.
5. The combination according to claim 1 wherein said plates are adjustable to compress a main portion of said reservoir chamber and effect an upper reservoir chamber portion having a greater width than the portion of the reservoir chamber between said plates when blood is disposed in said reservoir chamber.-
6. The combination according to claim 1 wherein at least one of said plates has a chamber therein, and said temperature varying means includes means for circulating heat exchange fluid through said chamber.
7. The combination according to claim 6 wherein said fluid is water.
8. The combination according to claim 1 further including upstanding frame means, and means hingedly connecting one of said plates to said frame means for pivotal movement toward and away from the other of said plates.
9. The combination according to claim 8 including means for connecting said oxygenation device to said frame means to support said oxygenation device between said plates.

Claims (9)

1. IN COMBINATION, A BLOOD OXYGENATION DEVICE INCLUDING AN OXYGENATOR CHAMBER, MEANS FOR INTRODUCING VENOUS BLOOD AND OXYGENATING GAS TO SAID OXYGENATOR CHAMBER FOR PRODUCING GAS BUBBLES IN THE BLOOD TO OXYGENATE THE BLOOD, A DEFOAMING CHAMBER CONNECTED TO RECEIVE BLOOD FROM SAID OXYGENATOR CHAMBER AND HAVING ANTI-FOAM MEANS THEREIN FOR ASSISTING IN THE REMOVAL OF EXCESS GAS AND VENT MEANS FOR VENTING EXCESS GAS TO ATMOSPHERE, AND A SUPPLE PLASTIC BLOOD SETTLING RESERVOIR CHAMBER CONNECTED TO RECEIVE BLOOD FROM SAID DEFOAMING CHAMBER, SAID RESERVOIR CHAMBER HAVING AN OUTLET FOR DISCHARGING OXYGENATED BLOOD, AND BLOOD TEMPERATURE CONTROL MEANS INCLUDING A HEAT EXCHANGER HAVING A PAIR OF RELATIVELY
2. The combination according to claim 1 wherein said adjustment means includes indicia to indicate the relative positions of said plates.
3. The combination according to claim 1 wherein said reservoir chamber and the other of said plates are transparent.
4. The combination according to claim 1 wherein said reservoir chamber portion comprises the major surface area of said reservoir chamber.
5. The combination according to claim 1 wherein said plates are adjustable to compress a main portion of said reservoir chamber and effect an upper reservoir chamber portion having a greater width than the portion of the reservoir chamber between said plates when blood is disposed in said reservoir chamber.
6. The combination according to claim 1 wherein at least one of said plates has a chamber therein, and said temperature varying means includes means for circulating heat exchange fluid through said chamber.
7. The combination according to claim 6 wherein said fluid is water.
8. The combination according to claim 1 further including upstanding frame means, and means hingedly connecting one of said plates to said frame means for pivotal movement toward and away from the other of said plates.
9. The combination according to claim 8 including means for connecting said oxygenation device to said frame means to support said oxygenation device between said plates.
US00265864A 1972-06-23 1972-06-23 Blood oxygenating device with heat exchanger Expired - Lifetime US3853479A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
US00265864A US3853479A (en) 1972-06-23 1972-06-23 Blood oxygenating device with heat exchanger
GB2219773A GB1398818A (en) 1972-06-23 1973-05-09 Blood oxygenation device
DE2324545A DE2324545A1 (en) 1972-06-23 1973-05-15 HEAT EXCHANGER
JP48057644A JPS4943492A (en) 1972-06-23 1973-05-23
BE131593A BE800124A (en) 1972-06-23 1973-05-28 BLOOD OXYGENATION DEVICE,
FR7321765A FR2189079B1 (en) 1972-06-23 1973-06-14

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US00265864A US3853479A (en) 1972-06-23 1972-06-23 Blood oxygenating device with heat exchanger

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US3853479A true US3853479A (en) 1974-12-10

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JP (1) JPS4943492A (en)
BE (1) BE800124A (en)
DE (1) DE2324545A1 (en)
FR (1) FR2189079B1 (en)
GB (1) GB1398818A (en)

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3918912A (en) * 1973-10-15 1975-11-11 Sherwood Medical Ind Inc Blood oxygenator
US4026669A (en) * 1975-07-14 1977-05-31 Baxter Laboratories, Inc. Variable capacity reservoir assembly
US4158693A (en) * 1977-12-29 1979-06-19 Texas Medical Products, Inc. Blood oxygenator
US4180896A (en) * 1977-12-29 1980-01-01 Texas Medical Products, Inc. Blood oxygenator assembly method
EP0080610A1 (en) * 1981-11-13 1983-06-08 Terumo Kabushiki Kaisha Blood circulating circuit for membrane-type artificial lung, and reservoir for use in blood circulating circuit
US4585056A (en) * 1984-04-18 1986-04-29 Norton Company Heat exchanger
US4637917A (en) * 1983-10-14 1987-01-20 Reed Charles C Bubble oxygenator
US5049146A (en) * 1989-05-31 1991-09-17 Baxter International, Inc. Blood/gas separator and flow system
US5125534A (en) * 1991-01-14 1992-06-30 Rose Barry L Beverage flavoring and dispensing apparatus and method of construction
WO1992017040A1 (en) * 1991-03-15 1992-10-01 In-Touch Products Co. Parenteral fluid warmer cassette, system and methods
US5381510A (en) * 1991-03-15 1995-01-10 In-Touch Products Co. In-line fluid heating apparatus with gradation of heat energy from inlet to outlet
US5589389A (en) * 1991-07-03 1996-12-31 Fondation Nationale De Transfusion Sanguine Apparatus for causing medicinal products to penetrate into red blood cells
US5846224A (en) * 1996-10-01 1998-12-08 Baxter International Inc. Container for use with blood warming apparatus
US6047108A (en) * 1996-10-01 2000-04-04 Baxter International Inc. Blood warming apparatus
USRE36774E (en) * 1989-10-01 2000-07-11 Baxter Healthcare Corporation Cylindrical blood heater/oxygenator
US6175688B1 (en) 1998-07-10 2001-01-16 Belmont Instrument Corporation Wearable intravenous fluid heater
US20140150991A1 (en) * 2011-05-20 2014-06-05 Equitec Holding B.V. Method for exchanging heat between a heat exchange fluid and a perishable product fluid, a removable heat exchange cartridge and a heat exchange system
US9737672B2 (en) 2007-08-07 2017-08-22 Belmont Instrument Corporation Hyperthermia, system, method, and components
US20170276402A1 (en) * 2016-03-23 2017-09-28 Wwt Technischer Geraetebau Gmbh Modular Blood Warmer
US20180274817A1 (en) * 2017-03-23 2018-09-27 Edwards Vacuum Llc Inline fluid heater
US10137257B2 (en) 2016-11-30 2018-11-27 Belmont Instrument, Llc Slack-time heating system for blood and fluid warming
US10485936B2 (en) 2016-11-30 2019-11-26 Belmont Instrument, Llc Rapid infuser with advantageous flow path for blood and fluid warming
US10507292B2 (en) 2016-11-30 2019-12-17 Belmont Instrument, Llc Rapid infuser with vacuum release valve
US11000407B2 (en) 2007-08-07 2021-05-11 Belmont Instrument, Llc Hyperthermia, system, method, and components

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3865703A (en) * 1973-04-19 1975-02-11 Diamond Shamrock Corp Electrowinning with an anode having a multicomponent coating
US3875043A (en) * 1973-04-19 1975-04-01 Electronor Corp Electrodes with multicomponent coatings
US4167663A (en) * 1977-01-24 1979-09-11 Baxter Travenol Laboratories, Inc. Blood warming apparatus
JPH0745582Y2 (en) * 1989-05-09 1995-10-18 帝人製機株式会社 Heating roller device

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US27100A (en) * 1860-02-14 Robert f
US2934067A (en) * 1957-09-12 1960-04-26 Charles L Calvin Blood oxygenating apparatus
US3207156A (en) * 1961-11-13 1965-09-21 Samuel I Lerman Heart-lung machine
US3291568A (en) * 1964-04-06 1966-12-13 Richard D Santter Cardio-pulmonary by-pass oxygenator unit
US3332746A (en) * 1963-03-29 1967-07-25 Single Cell Res Foundation Inc Pulsatile membrane oxygenator apparatus
US3374066A (en) * 1964-06-15 1968-03-19 William E. Farrant Thermostabilizer for extracorporeal oxygenator
US3493347A (en) * 1967-12-12 1970-02-03 Hazen F Everett Blood oxygenator
US3578411A (en) * 1969-07-22 1971-05-11 Bentley Lab Bubbler assembly for blood treating apparatus
US3729377A (en) * 1971-03-12 1973-04-24 Baxter Laboratories Inc Envelope oxygenator for blood having inflatable portions and process of using same

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3256883A (en) * 1963-08-08 1966-06-21 Wall Richard A De Oxygenator with heat exchanger
US3485245A (en) * 1967-06-21 1969-12-23 Ibm Portable fluid heater
US3590215A (en) * 1969-03-27 1971-06-29 Thermolyne Corp Clinical fluid warmer
US3640283A (en) * 1970-03-02 1972-02-08 Baxter Laboratories Inc Disposable blood-warming container

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US27100A (en) * 1860-02-14 Robert f
US2934067A (en) * 1957-09-12 1960-04-26 Charles L Calvin Blood oxygenating apparatus
US3207156A (en) * 1961-11-13 1965-09-21 Samuel I Lerman Heart-lung machine
US3332746A (en) * 1963-03-29 1967-07-25 Single Cell Res Foundation Inc Pulsatile membrane oxygenator apparatus
US3291568A (en) * 1964-04-06 1966-12-13 Richard D Santter Cardio-pulmonary by-pass oxygenator unit
US3374066A (en) * 1964-06-15 1968-03-19 William E. Farrant Thermostabilizer for extracorporeal oxygenator
US3493347A (en) * 1967-12-12 1970-02-03 Hazen F Everett Blood oxygenator
US3578411A (en) * 1969-07-22 1971-05-11 Bentley Lab Bubbler assembly for blood treating apparatus
US3729377A (en) * 1971-03-12 1973-04-24 Baxter Laboratories Inc Envelope oxygenator for blood having inflatable portions and process of using same

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Galletti et al., Temperature Regulating Devices and Heat Exchangers, Heart Lung By Pass; 2nd Printing; 2/66; Grune & Stratton; pp. 164 170. *

Cited By (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3918912A (en) * 1973-10-15 1975-11-11 Sherwood Medical Ind Inc Blood oxygenator
US4026669A (en) * 1975-07-14 1977-05-31 Baxter Laboratories, Inc. Variable capacity reservoir assembly
US4158693A (en) * 1977-12-29 1979-06-19 Texas Medical Products, Inc. Blood oxygenator
US4180896A (en) * 1977-12-29 1980-01-01 Texas Medical Products, Inc. Blood oxygenator assembly method
US4765959A (en) * 1981-11-13 1988-08-23 Terumo Kabushiki Kaisha Blood circulating circuit for membrane-type artificial lung, and reservoir for use in blood circulating circuit
US4717377A (en) * 1981-11-13 1988-01-05 Terumo Kabushiki Kaisha Blood circulating circuit for membrane-type artificial lung, and reservoir for use in blood circulating circuit
EP0080610A1 (en) * 1981-11-13 1983-06-08 Terumo Kabushiki Kaisha Blood circulating circuit for membrane-type artificial lung, and reservoir for use in blood circulating circuit
US4637917A (en) * 1983-10-14 1987-01-20 Reed Charles C Bubble oxygenator
US4585056A (en) * 1984-04-18 1986-04-29 Norton Company Heat exchanger
US5049146A (en) * 1989-05-31 1991-09-17 Baxter International, Inc. Blood/gas separator and flow system
USRE36774E (en) * 1989-10-01 2000-07-11 Baxter Healthcare Corporation Cylindrical blood heater/oxygenator
US5125534A (en) * 1991-01-14 1992-06-30 Rose Barry L Beverage flavoring and dispensing apparatus and method of construction
WO1992017040A1 (en) * 1991-03-15 1992-10-01 In-Touch Products Co. Parenteral fluid warmer cassette, system and methods
US5245693A (en) * 1991-03-15 1993-09-14 In-Touch Products Co. Parenteral fluid warmer apparatus and disposable cassette utilizing thin, flexible heat-exchange membrane
US5381510A (en) * 1991-03-15 1995-01-10 In-Touch Products Co. In-line fluid heating apparatus with gradation of heat energy from inlet to outlet
US5589389A (en) * 1991-07-03 1996-12-31 Fondation Nationale De Transfusion Sanguine Apparatus for causing medicinal products to penetrate into red blood cells
US6047108A (en) * 1996-10-01 2000-04-04 Baxter International Inc. Blood warming apparatus
US5846224A (en) * 1996-10-01 1998-12-08 Baxter International Inc. Container for use with blood warming apparatus
US6175688B1 (en) 1998-07-10 2001-01-16 Belmont Instrument Corporation Wearable intravenous fluid heater
US6236809B1 (en) 1998-07-10 2001-05-22 Belmont Instrument Corporation Wearable intravenous fluid heater
US6480257B2 (en) 1998-07-10 2002-11-12 Belmont Instrument Corporation Heat exchanger useable in wearable fluid heater
US11000407B2 (en) 2007-08-07 2021-05-11 Belmont Instrument, Llc Hyperthermia, system, method, and components
US9737672B2 (en) 2007-08-07 2017-08-22 Belmont Instrument Corporation Hyperthermia, system, method, and components
US20140150991A1 (en) * 2011-05-20 2014-06-05 Equitec Holding B.V. Method for exchanging heat between a heat exchange fluid and a perishable product fluid, a removable heat exchange cartridge and a heat exchange system
US10045657B2 (en) * 2011-05-20 2018-08-14 Equitec Holding B.V. Replaceable heat exchange cartridge employed in a heat exchange system for temperature control of a perishable fluid
US20170276402A1 (en) * 2016-03-23 2017-09-28 Wwt Technischer Geraetebau Gmbh Modular Blood Warmer
US10921021B2 (en) * 2016-03-23 2021-02-16 Wwt Technischer Geraetebau Gmbh Modular blood warmer
US10137257B2 (en) 2016-11-30 2018-11-27 Belmont Instrument, Llc Slack-time heating system for blood and fluid warming
US10485936B2 (en) 2016-11-30 2019-11-26 Belmont Instrument, Llc Rapid infuser with advantageous flow path for blood and fluid warming
US10507292B2 (en) 2016-11-30 2019-12-17 Belmont Instrument, Llc Rapid infuser with vacuum release valve
US11872382B2 (en) 2016-11-30 2024-01-16 Belmont Instrument, Llc Rapid infuser with advantageous flow path for blood and fluid warming, and associated components, systems, and methods
US20180274817A1 (en) * 2017-03-23 2018-09-27 Edwards Vacuum Llc Inline fluid heater

Also Published As

Publication number Publication date
BE800124A (en) 1973-09-17
FR2189079A1 (en) 1974-01-25
FR2189079B1 (en) 1976-06-11
JPS4943492A (en) 1974-04-24
DE2324545A1 (en) 1974-01-17
GB1398818A (en) 1975-06-25

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