Valve controlled single needle blood processing systems
United States Patent 3896803

Herein disclosed is a blood flow control system for use with a single needle for drawing blood from and returning blood to the blood channels of a patient. A needle is included which has a body with a pair of output channels leading into separate tubes. A switch is enclosed therein which provides a passage from the needle into either of the two selected channels. A switch block is attached to the needle body and is operable to cause switching from either of the two output blood channels in the needle. The switching is caused by a control circuit coupled to the switch block. The control circuit is operable depending upon the pressure of the blood in the input line of the two selected channels and causes the blood to flow from the needle to the first channel when the pressure applied to the second channel reaches a predetermined level. Upon switching, the blood is caused to flow from the processing equipment back through the needle into the patient.

Application Number:
Publication Date:
Filing Date:
Primary Class:
Other Classes:
604/44, 604/272
International Classes:
A61M1/30; (IPC1-7): A61M5/00; A61M1/03
Field of Search:
View Patent Images:
US Patent References:
3756234SINGLE NEEDLE DIALYSIS1973-09-04Kopp
3091239Apparatus for intravasal injection of gaseous and liquid media1963-05-28Moeller
3057370Three-way valve1962-10-09Hamilton
3048192Surgical valve1962-08-07Murphy
2835252Monitor apparatus for blood transfusions1958-05-20Mauchel
2261213Syringe adapter1941-11-04Bierman

Primary Examiner:
Truluck, Dalton L.
Attorney, Agent or Firm:
Sepulveda, Victor
Having thus described but one preferred embodiment of this invention what is claimed is

1. A blood access apparatus including:

2. A blood access apparatus comprising:

3. The blood access apparatus as defined in claim 2:

4. The blood acces apparatus as defined in claim 2 wherein:

5. The blood access apparatus as defined in claim 2 and further including:

6. The blood access apparatus as defined in claim 2 wherein:

7. Blood access apparatus as defined in claim 6 wherein:


This invention relates to medical equipment and more particularly to a novel and improved single needle blood control valve system for taking blood from and returning blood to a patients blood channel for processing in blood processors or the like.

Heretofore it has been known that a patient may for one reason or the other need the blood from a blood flow channel to be removed from his system, for processing and returned to a blood flow channel. As herein used the term blood flow channels may interchangeably refer to veins or arteries. For example, in some patients there is a failure of the vital organs, such as the kidneys, and the blood must be periodically removed from the patient and processed by dialysis machines or the like and returned to the patient. Such machines for performing these processes are well known to those skilled in the art, details thereof will not be gone into in this specification but will simply be referred to herein as a blood processor.

Presently there is much equipment on the market for performing the medical processes heretofore set forth. In most cases a needle is inserted into the blood channel of a patient, to facilitate the removal of blood from a patient. A second needle is placed into the blood channel for returning the blood to the patient. This, of course, is uncomfortable for the patient to have two needles inserted into his blood channels at the same time. After continued use of such needles into the blood channels of the person, the areas become scarred, sore and very discomforted.

More recently it has been discovered that a single needle can be used on a patient to eliminate much of the discomfort, the amount of scars and injury to the patient. One method of operating this particular single needle is periodically to remove the blood and then after a certain elapsed time return the blood to the person. Prior art devices have included a method of physically clamping the flexible hoses that are used so that blood flows in one direction and then unclamping that particular hose and clamping the other hose so that blood will reverse its flow in the other direction. In this particular type of operation, certain specified materials must be used according to standards set up by law. The flexibility of the tubing that must be used according to these standards is a somewhat soft plastic and the clamping operation is very slow because of the slow memory of tubing to return to its original shape. While this system has been used to some extent, it has proved to be somewhat unsuccessful.


The present invention overcomes the disadvantages heretofore set forth specifically by the fact that it eliminates the need for more than a single needle for blood processing operation and it also eliminates the need to clamp and unclamp hoses with this slow restoration rate.

Briefly described, the present invention provides a disposable needle which has become very popular with the present medical concerns because of the fact that the need for sterilization is eliminated whereby the needles are received into the medical facilities already sterilized and thus they can be disposed of without the need for being sterilized for reuse. The needle of the present invention is coupled to a body member which has a pair of channels therefor. One channel is provided for the output flow of blood and the other is for the input flow of blood. A switching valve is constructed within the body member which includes a cylindrical member having channels therein so that when it is turned in one direction, the channel connects the needle to the output channel or when rotated again or in a different direction it connects the input channel to the needle. Operability of the switch within the body member is accomplished by a switch block which is connected directly to the body member and has facilities therein for locking the switch member to the body member.


These and other features and advantages will become more apparent to those skilled in the art when taken into consideration with the following detailed description wherein like references numeral indicate like and corresponding parts throughout the several views and wherein:

FIG. 1 is a schematic drawing of the valve control system of one embodiment of the present invention;

FIG. 2 is an exploded view of the valve and valve switch used in the system shown in FIG. 1;

FIG. 3 is a top view of the valve and valve switch 2 with the valve and valve switch disassembled;

FIG. 4 is a side view of the valve and valve switch 3 taken along the lines 4--4 of FIG. 3;

FIG. 5 is a section view of the valve and valve assembly taken along the lines 5--5 of FIG. 4;

FIG. 5A is a section view of the valve and valve assembly as shown in FIG. 5 with the valve switched to a second position; and

FIG. 6 is a section view taken along the lines 6--6 of FIG. 3.


Referring now to FIG. 1 there is shown the valve control system of the present invention showing a switch 104 which is used to transfer blood flow either into or out of the arm of the patient 100 through a needle 102. Specifically two tubes 106 and 108 leads from the switch 104 into a pump 110 which is driven by a motor 112. Pump 110 pumps the blood from the needle 102 to the switch 104 into a blood processor 113. The blood processor may be of the type such as an artificial kidney which is used to clean the blood from the system and return it via line 108.

An output tube 114 from the blood processor 113 leads through a drip chamber 116 which is connected into tube 108 back into the switch 104. The purpose of the drip chamber 116 is to give a visual indication of blood flowing in the output tube 114 and will be explained in more detail hereinafter.

The switch 104 is operated from the switch control circuit 120 by a mechanical linkage 122 therefrom. The mechanical linkage may preferrably be in the form of a cable. By manipulation of the mechanical linkage 122 blood is allowed to either flow from tube 106 with tube 108 being shut off or from tube 108 with tube 106 shut off. Thus blood may be alternately pumped from the switch 104 into the blood processor and then alternately switched so that the blood flows from the tube 108 with the tube 106 shut off. Thus, a single needle can be used into the patient's arm and blood can be alternately pumped from and back into the patient.

The switch control circuit is operable when the pressure of the blood in the line 108 raises to a predetermined level. Specifically a pressure sensing tube 124 is connected into the drip chamber 116 in a suitable manner and connected into the pressure transducer 126. Such pressure transducers are well known to those skilled in the art and provide an electrical signal when the pressure builds up in transducer to a predetermined level. After the predetermined level is reached, an electrical signal (of a certain level) is emitted from the lead 128 and activates a switch 130. Specifically, a line 128 leads through an adjustment potentiometer 132 and into a suitable electrical switch 130 which has one end coupled to a voltage source 134 and the other end of which is coupled to a solenoid 136. The other end of the solenoid 136 coupled to a ground potential 138.

Switch 130 may be a suitable time delay switch which are well known to those skilled in the art.

Solenoid 136 operates the mechanical linkage 122 into the switch 104. Specifically the solenoid can be coupled to a suitable cable which has one end thereof coupled directly into the switch 104 and when the switch 130 is activated, solenoid 136 pulls the cable in a suitable direction. The cable then may be suitably spring loaded so that when the switch is deactivated the cable 122 moves back into its original position. Thus switching the flow of blood through leads 106 or 108, respectively.

To operate the pressure transducer 126 the drip chamber 116 may be comprised of a soft clear plastic enlargement in the tubing for measuring pressure in the lines and which is also the pressure in the blood processor or artificial kidney. A certain amount of air is placed into the drip chamber which lowers the blood level 140 in order that the pressure may be checked. The pressure gage may, for example, be a set of bellows or the transducer 126 as shown.

The drip chamber 116 establishes the fact that the blood is actually flowing through the lines. For example, the level of the blood 140 can be checked by visual observation that blood is actually flowing. Without the drip chamber 116, one might observe that there is pressure in the blood flow lines 106 or 108 but not that it is actually moving.

A problem occurs in a situation where there is an air level in the drip chamber 116. It must be essential that the blood flow level does not drop to a point whereby air enters into the patient's blood system. Thus, constant observation of the blood flow level must be made. In this shown embodiment there is a system which provides automatic detection of the level of the blood. For example, a suitable light 142 is stationed on the lower end of the chamber 116 and a photo detector 144 is positioned on the opposite side of the tubing. Thus, light will not flow through the tubing 108 as long as there is blood therein because of the dark denseness of the blood. The light will not be detected by the photo detector 144. If the blood level 140 drops below the visual alignment of the photo detector 144 for light 142, an electrical signal provided by the terminal 146 will be applied to a suitable alarm 148 to alarm personnel in the facilities that the blood level has dropped to an unsafe position. Also an electrical signal from photocell 144 is applied to a line 150 which energizes a solenoid 152 which de-energizes a switch 156 to cut off all power to the blood processor 113 and the motor 112 to discontinue the flow of blood into or from the patient. The solenoid 136 is activated, causing the valve to switch to closed position so air cannot go into vein. A warning light indicator goes on indicating "air" in line.

A time delay switch 160 is coupled into a solenoid 152 so that at certain time periods the solenoid 152 will open the switch 162 which leads from a voltage source on terminal 164 into a voltage controlled amplifier 168 which is used to energize motor 112. Time delay switch 160 is automatically reset by the signal from the pressure transducer 126.

In operation the needle 102 is placed into the patient's arm 100 and a switch 104, which will be explained in more detail hereinafter, is switched to tube 106 so that when the pump 110 is energized by the motor 112, blood is pumped from the patient's arm into the blood processor 113 and into tube 108 but because the tube 108 is cut off at the switch 104, it is unable to return to the patient's arm 100. Thus, pressure builds up in the drip chamber 116 and this pressure is applied through the tube into the pressure transducer 126. When the pressure transducer 126 reaches a predetermined level, an electrical signal is generated in the transducer 126 and applied to the switch 130 which energizes the solenoid 136 and mechanically manipulating the mechanical linkage 122 which switches the switch 104 to cut blood flow in the tube 106 and start blood flow in the tube 108. Blood then starts to flow from the blood processor 113 into the patient's arm to the needle 102 until such time as preset time delay is reached, causing mechanical manipulation of the mechanical linkage 122 and reversing the switch 104. This causes periodic time onto the pressure transducer which is rhythmetic to a certain extent. As long as this same rhythm is maintained, the time delay 160 will never reach its maximum time and will be continuously reset by the signal. on lead 128 thereto. If a malfunction occurs some place in the system, for example, the needle come loose from the patient's arm, a break in the tube 106 or 108, or a failure in the blood processor, the time delay 160 will be extended because pressure fails to raise in the pressure transducer 126. If the set time of the time delay 160 is exceeded, solenoid 152 is engaged which will enable the solenoid 136 causing a change in the linkage reversing switch and also to an extent where the switches are cut off and the power supply to the entire unit is disconnected causing the pump to stop.

A further safety occurs in the present invention when the pump 110 is operating and the switch 104 is cut off to the tube 106. If the pump continues to operate, a negative pressure will be built up in the blood flow line which will cause damage to the blood, specifically it will cause certain destructive damage to the blood cells themselves. Therefore, it would be desirous to reduce the speed of the motor 112 to a bare minimum. To accomplish this a voltage control amplifier 168 is coupled between the motor 112 and the output of the switch 130. When a signal appears on the solenoid 136, it also reduces the voltage supply to motor 112 through the voltage control amplifier 168. The motor continues to operate but at a reduced speed eliminating the chance of any blood cell damage due to negative pressure.

Referring now to FIGS. 2-6 collectively, there is shown a disassembled view of the switch 104, which comprises a valve 200 and a valve body 201. The valve body 201 secures the needle 102 therein and has a hole 202 drilled in the underside thereof as shown in FIG. 2, and a pair of further holes 204 and 206 which communicate into the hole 202 by means of passages 208 and 210. Note that the passage 208 from hole 204 is slanted inwardly to communicate with the hole 202 while the passage 210 in the hole 206 is straight and communicates directly into the hole 202. The tube 106 is secured into the hole 204 and the tube 108 is secured into the hole 206 so that flow of the blood from the needle 102 can be directed into tubes 106 and 108 through the appropriate passages and holes. This is accomplished by a valve 200.

As shown in FIG. 5 the valve 200 comprises a stragiht through hole or channel 212 which when properly aligned communicates the holes through the needle 102 into the passage 210 so that blood will flow directly to tube 108. By turning the valve 200 the hole 212 communicates into the passage 210. An off-shoot passage 214 from the passage 212 communicates the hole in the needle 102 into the passage 208 so that blood is now sent into the tube 106.

Specifically the valve 200 comprises a cylindrical body which fits into the hole 202. An O ring 215 is placed around the outside periphery of the cylindrical body valve 200 to assure a seal therein so that blood will not leak around the passage but wiil be directly communicated into its proper hole 204 and 206 and its proper tube 106 and 108 respectively. The outward side of the valve 200 has a protruding tongue which is used to manipulate the rotation of the valve 200 within the hole 202 in a manner hereinafter described.

The entire valve assembly is coupled directly to the needle 102. The tubes 106 and 108 are manufactured specifically of an inexpensive material so that it can be disposed of after use. A switching member 220 or switching block comprises a plastic body which has a hole 222 therein so that the cable 122 can be placed therein to manipulate the valve 200. To accomplish manipulation of the valve 200 a channel 224 is cut in one side of the block which has a specific configuration which matches the configuration of the valve body in 201 which will be explained in more detail hereinafter. A hole 226 is drilled to the top side of the channel 224 and communicates with the hole 222 drilled therein. The hole 226 communicates with the hole 222 and receives a gear 228 therein which has a groove 230 that matches the tongue 218 on the switch 200. A rack 232 is coupled to a insert 234 by suitable pin 236 and is coupled to the cable 122 and inserted into the bore 222. The bore 222 has smaller holes 240 therein so that the insert 234 cannot slide further than necessary to accomodate operations hereinafter explained.

The rack 232 engages the teeth on the gear 228 and when the cable is moved forward or backward it causes the gear 228 to rotate and also the switch 200. When the switch 200 is moved for example as shown in FIG. 5 a straight through passage from the needle into tube 210 occurs. On the other hand when the gear is engaged and moves in the opposite direction passage 214 communicates the needle into passage way 208 as best shown in FIG. 5A.

A tubular cylinder 242 has threads 246 therein which matches the threads 248 in the hole 222. A spring 250 is placed around the cable 122 and on the outside of the insert 234. The gear 232 and insert 236 is inserted into the hole 222. The cable is then placed through the center of the cylinder 242. Thereafter the spring 255 is placed within the hole 222 and the cylinder 242 is threadly mounted to the threads 248 of the hole 222 holding the spring and rack gear in place. Thus by pulling the cable in one direction and holding it there the switch switches from one direction to the other and upon release the spring action thereof changes back to its original position.

The configuration of the valve body 201 is shaped specifically as shown in FIGS. 2, 3, 5, and 5A. This configuration matches the configuration of the channel 224 so that the valve body 201 can be snapped into the channel 224. A pair of locking lips 250 and 252 protrude inwardly from the small end 254 of the channel 224. A pair of grooves 256 and 258 are provided in the matching small end of the valve body and fit the lips 250 and 252 respectfully. Thus the body 201 can be placed in the channel 224 and pushed forward to effect locking there between. This locking prevents the body from moving outwardly from the switch body.

To further facilitate locking the valve body 201 includes a second groove 260 which is L shaped. A further lip 262 protrudes inwardly from channel 224 and engages the groove 260.