US2844147A

US2844147A - Segregation chamber for transfusion sets

Info

Publication number: US2844147A
Application number: US503684A
Authority: US
Inventors: Robert C Beachman
Original assignee: Cutter Laboratories Inc
Current assignee: Bayer Corp
Priority date: 1955-04-25
Filing date: 1955-04-25
Publication date: 1958-07-22
Anticipated expiration: 1975-07-22

Description

July 22, 1958 R. c. BEACHAM SEGREGATION CHAMBER FOR TRANSFUSION SETS Filed April 25, 1955 IN VEN TOR. Poundiam? WL LM Irma/w)? United States Patent SEGREGATI ON FOR TRANSFUSION Robert C. Beachman, Richmond, Califi, assignor to Cutter Laboratories, Berkeley, Calif., a corporation of California Application April 25, 1955, Serial No. 503,684

2 Claims. (Cl. 128--214) This invention relates to transfusion sets and in general has for its object the provision of a segregation chamber for inclusion in said sets and by which air embolisms in patients receiving transfusions can be avoided.

As is well known, intravenous solutions are administered from a flask or bottle through a section of flexible tubing connected at its free end to a hypodermic needle. Since air embolisms should of course be avoided, all air contained within the flexible tubing should be completely displaced with the solution to be administered prior to the insertion of the hypodermic needle into the patient. Up to the present, this has entailed arather tedious and time consuming manipulation of the tubing. Furthermore, as the end of the administration approaches and the solution has been substantially drained from its container, care again must be taken to insure that no air becomes entrained in the solution and which might thereby result in an embolism. In short, with transfusion sets now commercially available there is danger of producing air embolisms both at the beginning as well as at the end of an administration. Furthermore, the problem has been made more acute due to two additional factors. Customarily a drip meter, oftentimes in combination with a filter, is inserted in the transfusion line, the drip meter chamber being a site at which additional air can be entrained in the intravenous solution. nous solutions are administered under pressure to give rapid transfusions. Although this pressure is not great, nevertheless it can be the cause of an increase in the amount of air entrained in the solution particularly at the site of the drip meter. p

More specifically then, it is the object of this invention to provide an air segregator in combination with a drip meter for insertion in the line of :a transfusion set, the segregator being provided adjacent its base with a guided float valve for permitting deaerated solution to pass into the'tubing leading to the injection needle and for closing off the outlet port of the segregator upon the depletion of its solution content.

The invention possesses other advantageous features, some of which, with the foregoing, will be: set forth at length in the following description where those forms of the invention which have been selected for illustration in the drawing accompanying and forming a part of the present specification, are outlined in full. In said drawing, three forms of the invention are shown, but it is to be' understood that it is not limited to such forms, since the invention as set-forth in the claims may be embodied in other forms.

Referring to the drawings:

Fig. 1 is a side elevation of an air segregator embodying the objects of my invention, the lower half thereof being shown in mid-section the better to illustrate its construction and operation.

Fig. 2 is a vertical mid-section of a modified form of my invention. 1

Fig. 3 is a transverse section takenon the section line 3-3 of Fig'. 2.

Fig. 4 is a vertical mid-section of a further modification of my invention.

Frequently intraveice Fig. '5 is a transverse section taken on the section line 5-5 of Fig. 4.

As illustrated in Fig. 1, the-objects of my invention have been embodied in a combination air segregator and drip meter comprising a transparent plastic cylindrical chamber 1 having an integrally formed top 2 and an integrally formed hollow connection spike 3 terminating at its lower end in a drip nipple 4. Extending into and sealed to the lower counterbored end of the chamber 1 is a bottom cap 5 provided with an outwardly extending marginal flange 6 overlying the lower end of the chamber and forming a labyrinth seal therewith. Depending from the cap 5 is an outlet nipple 7 having a bore 8 merging at its upper end with a counterbore 9 defined by a boss 11 having an inclined marginal valve seat 12. Mounted in the counterbore 9 is an upstanding overflow nipple 13 and which also serves as a float valve guide. Disposed over the overflow nipple 13 is an inverted cup 14 formed of any suitable material having a specific gravity somewhat less than the range of specific gravities of intravenous solutions in general use. The inner peripheral surface of the lower end of the cup or float valve 14 is inclined so as to mate with the valve seat 12 and the height of the overflow guide nipple should of course be such as to permit the valve 14 to seat on its valve seat 12.

In the use of this device the connecting spike 3 is connected either directly with an intravenous solution bottle or indirectly therewith through a section 15 of flexible tubing. The outlet nipple 7 is connected through a sec-' tion 16 of flexible tubing with a hypodermic needle, this section of tubing being provided with a pinch valve. This having been done the bottle is suspended in an inverted position whereupon solution flows into the air segregator. By then tipping the segregator the valve closure cup 14 can be unseated whereupon air disposed within its confines and above the solution level passes into the nipple 13. As soon as sufiicient solution has flowed into the segregator to float the cup 14, it can be uprighted. As this point the bottom of the cup will assume a level indicated by the dotted line 17 somewhat below the upper end of the nipple 13, the level of the solution being indicated by the line 18. In this positoin then, the cup serves to establish a liquid seal between the mouth of the nipple 13 and that portion of the segregator lying above the solution level. As a result of this liquid seal the further passage of solution through the segregator takes place without the entrainment of air therein, and this in spite of the fact that air is contained within its upper portion and also within the upper end of the cup 14. As solution continues to pass through the nipple 13, nipple 7 and the tubing section 16, it will of course displace any air contained therein. having been done, the operator or attendant can now proceed to make his injection.

When the bottle has been depleted of solution, the solution level in the segregator will of course drop, thereby allowing the lower end of the cup to seat on the valve seat 12 thereby to preclude the further passage of solution to the tube section 16.

It will therefore be seen that I have provided a device for insertion into a transfusion set whereby any air entrained in the system can be readily displaced with solution, whereby the incorporation of air into the solution during an administration is precluded and whereby the flow of solution through the tubing leading to the hypodermic needle is shut off upon the depletion of the solution from the solution bottle. Furthermore, this device, has been incorporated in combination with a drip meter, the nipple 4 serving this purpose.

As illustrated in Figs. 4 and 5, the objects of my invention can also be embodied in a segregator comprising a cylindrical chamber 21 closed at its upper end and provided at its lower portion with a counterbore 22. Formed I This integral with the top 23 ofthe chamber is a downwardly depending drip nipple 24 merging with an upwardly extending tapered spike 25 serving as an inlet to the chamber- 21. Closing the lower end of the chamber 21 is a bottom 26 having a labyrinth seal with the chamber 21in the same fashion as described with reference to the modification illustrated in Fig. 1. Depending from the bottom 26 is 'an outlet nipple 27, the lower end of which is connected to a section 28 of flexible tubing provided at its free end with a hypodermic needle and adapted to be provided intermediate its ends with a pinch valve not shown. The upper end of the bore 29 of the nipple 27 is surrounded by an annular valve seat 31. Disposed within the lower end of the chamber 21 is a cylindrical float closure member or valve 37 provided on its outer walls with longitudinally extending ribs 33, these ribs having a free sliding fit with the inner diameter of the counterbore 22 and serving to define passageways 34 for establishing communication between the free end of the chamber 21 and its lower end. The lower face of the float valve 32 is arranged to seat on the annular valve seat 31 thereby to close off the upper end of the bore 29. The upper end 35 of the counterbore serves to limit the upward movement of the float valve 32. Extending through the upper portion of the chamber 21 is a vent hole 36 for establishing communication between that portion of the chamber lying above the float and atmosphere.

In the use of this modification of my device the spike 25 is connected either directly to an intravenous solution bottle or indirectly thereto through a section 37 of flexible tubing. This having been done, the solution bottle is suspended in an inverted position thereby to permit solution to flow through the tubing section 37 and through the drip nipple 24 into the chamber 21. The solution so delivered to the chamber passes downwardly through the passageways or channels 34 to the lower end of the chamber, thereby to float the float valve 32. Here it should be noted that the cross-sectional area of the Dassageways or channels 34 should be sufliciently small so that solution contained therein serves as an air seal. In other words, once these passageways have been filled with solution, the solution contained therein will serve to block oflf the further passage of air therethrough. When the float valve 32 has been unseated, solution will be free to pass through the passageways 34 from the upper end of the chamber into the nipple 27 and through the nipple and the tubing section 28 to the hypodermic needle. The initial portions of solution passing through the nipple 27 and tubing section 28 will serve to displace all air entrained therein. Once all air has been excluded from these members the device is ready for the purpose of making an intravenous injection for the air seal constituted by the solution contained in the passageways 34 will thereafter preclude the further passage of air from the upper end of the chamber 21 to its lower end. During the initial operation of the device, that is, during the time that the float valve 32 is rising, a certain amount of air from that portion of the chamber above the valve 32 will escape through the vent 36.

It will therefore be seen that this modification like the modification shown in Fig. 1 serves as a device for readily clearing the line of entrained air prior to the administration of an intravenous injection, serves to avoid the entrainment of air with the solution during the administration and serves to close the outlet of the segregation chamber when the intravenous solution bottle has been depleted of its contents.

In Figs. 2 and 3 the objects of my invention have been embodied in a cylindrical chamber 41 closed at its upper end by a top 42 and having a labyrinth seal at its lower end with a bottom 43. Extending into the top 42 is a drip nipple 44 merging with an upwardly extending tapered spike 45 adapted to be connected either directly to an intravenous solution bottle or indirectly thereto through a section 46 of flexible tubing. .Formedat one side of the lower portion of the chamber 41 is a cylindrical float guide 47 having a slot 48 on its inner side.

Formed integral with the bottom 43 in vertical registration with the cage 47 is a connecting nipple 49, the lower end of this nipple being secured to a section 51 of flexible tubing, the free end of which is arranged to be connected with a hypodermic needle. The upper end of the nipple 49 terminates in the valve seat 52 extending upwardly into the valve cage-47. Disposed Within the valve cage 47 and freely' :slidable therein is a hollow float valve 53 arranged in its lower position to seat on the seat 52, thereby to close off communication between the. chamber 41 and the nipple 49. Extending through the thickened side wall of the chamber 41 in vertical alignment with valve cage 47 is a vent hole 54.

In the operation of this device, it is connected to an intravenous solution flask in the same manner as above explained with reference to the modifications described in Figs. 1, 4 and 5. When the intravenous solution bottle is inverted, solution passes through the drip nipple 44 to the lower end of the chamber and into the slot 48 of the valve cage. This serves to unseat the fioat valve 53 whereupon a certain amount of aircontained within the chamber passes upwardly through the vent hole 54. Simultaneously solution starts to pass downwardly through the nipple 49 and its connected tubing section 51, this solution serving to displace the air contents of these two members. When a solid column of solution has filled the nipple 49 and the tubing section 51, the device is ready for use in administering the solution. During the administration of the solution, the flow of solution through the nipple 44, drop by drop, is controlled by a pinch valve associated with the tubing section 51 and although air is contained within the chamber 41, no air is entrained with the solution passing downwardly through the nipple 49 during the administration procedure. When the contents of the intravenous solution bottle has been depleted and the level of the solution within the chamber 41 drops, the float valve 53 likewise drops to its seat 52, thereby precluding the further passage of solution through the system and thus avoiding the entrainment of air with any portion of the solution reaching the patient.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. An air segregator for transfusion sets comprising: a segregation chamber provided at its upper end with an inlet port and at its lower end with an outlet port, said outlet port being circumscribed by a valve seat extending upwardly into said chamber; an inverted cup disposed in said chamber in vertical alignment with said outlet port; and means within said chamber for constraining said cup to move into registration with said valve seat upon the downward movement of said cup.

2. An air segregator for transfusion sets comprising: a segregation chamber provided at its upper end with an inlet port and at its lower end with an outlet port, said 3 outlet port being circumscribed by an inclined valve seat extending upwardly into said chamber; an inverted cup disposed in said chamber in vertical alignment with said outlet port; and means within said chamber for constraining said cup to move into registration with said .valve seat upon the downward movement of said cup, the lower peripheral edge of said cup being tapered to mate with said valve seat.

References Cited in the file ofthis patent UNITED 'STATES PATENTS 1,788,280 Dempsey Jan. 6, 1931 2,693,801 Foreman Nov. 9, 1954 2,729,212 Butler Jan. 3, 1956 2,784,733 Martinez Mar. 12, 1957 FOREIGN PATENTS 11,074 Germany Sept. 28, 1880