Two-way outdwelling slit valving of medical liquid flow through a cannula and methods

• US 5,205,834 A
• Filed: 06/24/1992
• Issued: 04/27/1993
• Est. Priority Date: 09/04/1990
• Status: Expired due to Term

• Current Assignee: Navilyst Medical Incorporated (AngioDynamics, Inc.)
• Original Assignee: Moorehead H. Robert, Thomas A. Wiita
• Inventors: Wiita, Thomas A., Moorehead, H. Robert
• Primary Examiner(s): Yasko, John D.
• Assistant Examiner(s): Gutowski, Anthony
• Application Number:
  US07/903,410
• Time in Patent Office: 307 Days
• Field of Search: 604/30, 604/31, 604/167, 604/246, 604/247, 604/257, 137/493, 137/493.1, 137/493.8, 137/493.9, 137/512.4, 137/843-845, 137/859
• US Class Current: 604/247
• CPC Class Codes: A61M 2039/242 designed to open when a predetermined pressure or flow rate has been reached, e.g. check valve actuated by fluid
• CPC Class Codes: A61M 2039/2426 Slit valve
• CPC Class Codes: A61M 39/22 Valves or arrangement of valves A61M39/02, A61M39/0247, A61M39/16 take precedence; regulating valves in infusion systems A61M5/16881; in devices worn by the patient for the reception of urine, faeces, catamenial or other discharge, or in colostomy devices A61F5/4405
• CPC Class Codes: A61M 39/24 Check- or non-return valves
• CPC Class Codes: F16K 15/147 the closure elements having specially formed slits or being of an elongated easily collapsible form
• CPC Class Codes: Y10T 137/778 Axes of ports co-axial
• CPC Class Codes: Y10T 137/7843 Integral resilient member forms plural valves
• CPC Class Codes: Y10T 137/7881 Apertured plate

Abstract

A cardiovascular outdwelling, normally closed, pressure-responsive slit valve liquid flow control and related methods wherein a diaphragm having a slit therein is flexed distally by hydrostatic pressure and proximally by negative pressure at different points in time to selectively open the slit and accommodate the flow of IV solution to a medical patient through a cannula and blood sampling from the cardiovascular system of the patient through the cannula in such a way as to prevent bleed-back and clotting of blood within the cannula.

Claims

1. A method of controlling medical liquid flow in a cannula comprising the steps of:

placing a distal end of the cannula indwelling within an internal body cavity of a medical patient;

connecting a distal end of an outdwelling slit valve housing directly to a proximal end of the cannula in selective internal medical liquid communication along a predetermined flow path solely due to pressure differential;

causing a substantially planar normally closed slit diaphragm comprising a centrally disposed slit of predetermined length comprising lips normally disposed in tight edge-to-edge relation and otherwise being impervious to be interposed across the flow path within the housing;

connecting a proximal end of the outdwelling slit valve housing directly to a distal end of a tube having a proximal end connected to an effluent only source of medical liquid which provides a predetermined distally directed pressure;

creating a negative pressure at an outdwelling site proximal of the slit diaphragm but remote from the source of a magnitude such that the diaphragm is thereby flexed proximally and the lips of the slit are opened proximally to accommodate unidirectional distal-to-proximal medical liquid flow through the slit from the body cavity of the patient to the remote site.

2. The method according to claim 1 comprising the further step of physically limiting the area of the diaphragm which is permitted to flex proximally to only a predetermined central portion of the total distal area of the diaphragm.

3. The method according to claim 1 comprising the further step of physically altering the pressure differential by altering the negative pressure to cause imposition of an opposite predetermined pressure differential across the diaphragm thereby flexing the diaphragm distally, opening the slit therein and causing proximal-to-distal flow of medical liquid through the slit directly from the effluent only source to the patient.

4. The method according to claim 1 comprising the further step of physically limiting the area of the diaphragm which is permitted to flex distally to only a predetermined central portion of the distal area of the diaphragm.

5. Two-way valve structure for disposition external of a body of a medical patient by which physiological liquid flow to and physiological liquid flow from an internal body cavity site is selectively accomplished, the valve structure comprising:

housing means comprising proximal liquid ingress and egress flow port means, distal liquid ingress and egress flow port means and a hollow interior defining a single flow path along which physiological liquid selectively flows;

slit valve means sealingly and transversely disposed within the hollow interior of the housing means and comprising substantially planar diaphragm means of generally uniform thickness in which at least one central normally closed slit comprising edge-to-edge lips is disposed, the diaphragm means further comprising peripheral means imperviously secured to the housing means and solid means interposed between the peripheral means and the lips, the lips being contiguous in tight edge-to-edge relation when the diaphragm means are unflexed, the diaphragm means being contiguous with first and second solid wall means respectively apertured only at a central location aligned with the slit, the central apertures of the first and second solid wall means in combination with said diaphragm means accommodating selective flexing of the lips from a tightly closed to an open position in either direction only when either of first and second predetermined physiological liquid pressure differential thresholds is exceeded, the first solid wall means distal of the diaphragm means controlling at least in part the flex and setting one physiological liquid pressure differential required to open the slit in a distal direction at and solely because of a relatively low differential value and the second solid wall means distal of the diaphragm means controlling at least in part the flex and setting the pressure differential required to open the slit in a proximal direction at and solely because of a relatively high pressure differential value.

6. A method of controlling liquid flow to a hollow cannula comprising the steps of:

causing a normally closed planar slit diaphragm to be disposed across a flow path in an outdwelling valve structure;

placing a distal end of the cannula indwelling within a medical patient;

connecting a distal end of the valve structure to the proximal end of the cannula, thereby placing the flow path of the valve structure in communication with the hollow of the cannula;

imposing a gravity-caused liquid pressure from a discharge only clean external source of liquid disposed above the patient for gravity liquid infusion upon a proximal side of the diaphragm;

flexing the diaphragm distally only when the collective liquid pressure upon the diaphragm is distally directed and exceeds a selectively predetermined threshold magnitude; and

opening a slit in the diaphragm distally and causing an initial one directional proximal-to-distal flow of the clean liquid only through the slit directly from the discharge only source at least in part under force of gravity to the cannula and thence to the patient;

closing the slit in the diaphragm to stop liquid infusion before flow reverses when the gravity caused pressure is reduced as liquid from the source is spent.

7. A method of controlling uncontaminated medical liquid flow in a cannula comprising the steps of:

placing a distal end of the cannula indwelling within a medical patient;

connecting a hollow distal end of an outdwelling slit valve housing to a proximal end of the cannula in selective internal liquid communication along a predetermined liquid flow path;

causing a normally closed planar slit diaphragm to be securely interposed across the flow path within the housing;

creating a liquid pressure differential across the diaphragm between a pressure internal of the patient and a pressure caused at least in part by gravity operating upon a discharge only uncontaminated liquid source;

flexing the diaphragm distally when the liquid pressure differential is controlled by the pressure of the discharge only source so as to exceed a selectively predetermined threshold pressure without human intervention; and

opening distally the slit in the diaphragm only while the flow is proximal-to-distal and causing one way proximal-to-distal flow of uncontaminated liquid through the open slit from the discharge only source directly to the patient.

8. A method of selectively controlling medical liquid flow from a discharge only uncontaminated medical liquid source along tubing directly to a patient, comprising the steps of:

placing a distal end of the tubing indwelling within a medical patient and connecting the proximal end of the tubing to the source;

placing an outdwelling slit valve housing, comprising a planar slit diaphragm, securely between distal and proximal parts of the tubing to create a one-way selectively operable internal liquid communication flow path directly to the patient;

imposing a pressure from within the patient upon a distal side of the diaphragm;

imposing a one-way only liquid pressure having at least a gravity component from the discharge only source upon a proximal portion of a diaphragm securely disposed within the slit valve housing to create a pressure differential which is controlled by the pressure of the discharge only source without human intervention so as to have sufficient selectively predetermined magnitude to flex the diaphragm distally to open a slit in the diaphragm and cause proximal-to-distal flow from the discharge only source through the slit to the patient along the tubing until the magnitude of the pressure differential falls below the selectively predetermined amount;

closing the slit of the diaphragm so as to avoid reflux in response to said lowering of the pressure differential below said selectively predetermined amount.

9. A method of selectively controlling medical liquid flow in tubing comprising the steps of:

placing a distal end of the tubing indwelling within a medical patient;

connecting a distal end of an outdwelling slit valve housing to a proximal end of the tubing in selective internal medical liquid communication along a predetermined flow path;

causing a substantially planar normally closed slit diaphragm comprising a slit of predetermined length comprising lips normally disposed in tight edge-to-edge sealed relation and otherwise being impervious to be interposed across the flow path within the housing;

connecting a one-way source of uncontaminated liquid in one-way flow relationship only to a proximal end of the housing thereby creating a liquid pressure differential, at least due in part to gravity, of at least a selectively predetermined magnitude across an area of the diaphragm in which said slit is disposed to only thereby flex the diaphragm distally to unseal and open the lips of the slit and to accommodate proximal-to-distal uncontaminated medical liquid flow across the open lips of the slit without reflux directly into the tubing and thence directly to the patient, said slit returning to a closed unflexed sealed state when the gravity caused positive liquid pressure differential is positive but falls below the selectively predetermined magnitude.

10. A method of selectively controlling medical liquid flow in tubing comprising the steps of:

placing a distal end of the tubing indwelling within a medical patient;

connecting a distal end of an outdwelling slit valve housing to a proximal end of the tubing in selective internal medical liquid communication along a predetermined flow path;

causing a substantially planar normally closed slit diaphragm comprising a slit of predetermined length comprising lips normally disposed in tight edge-to-edge sealed relation and otherwise being impervious to be interposed across the flow path within the housing;

connecting a one-way source of uncontaminated liquid in one-way flow relationship only to a proximal end of the housing thereby creating a liquid pressure differential, at least due in part to gravity, of at least a selectively predetermined magnitude across an area of the diaphragm in which said slit is disposed to only thereby flex the diaphragm distally and open the lips of the slit and to accommodate proximal-to-distal uncontaminated medical liquid flow across the open lips of the slit directly into the tubing and thence directly to the patient;

altering the liquid pressure differential across the diaphragm causing the diaphragm to flex proximally, physically limiting the area of the diaphragm which is permitted to flex proximally to only a predetermined central portion of the proximal area of the diaphragm and causing distal-to-proximal liquid flow across the diaphragm to a site other than said one-way source.

11. Two-way structure for disposition external of a body of a medical patient by which physiological liquid flow to and physiological liquid flow from an internal body site is selectively accomplished, the valve structure comprising:

housing means comprising proximal liquid ingress and egress flow port means, distal liquid ingress and egress flow port means and a hollow interior defining a single flow path along which physiological liquid flows in a desired direction;

bi-directional displaceable, pressure responsive slit valve means sealingly and transversely disposed within the hollow interior of the housing means and comprising substantially planar diaphragm means of generally uniform thickness in which at least one central normally closed slit comprising edge-to-edge lips is disposed, the diaphragm means further comprising peripheral means imperviously secured to the housing means and solid means interposed between the peripheral means and the lips, the lips being contiguous in tight edge-to-edge relation when the diaphragm means are unflexed, the slit valve means further comprising first and second solid wall means respectively apertured only at a central location aligned with the slit, the first and second solid wall means being contiguous with the diaphragm means other than at the central aperture of each of said first and second solid wall means when the diaphragm means are unflexed and which comprise peripheral edges also secured to the housing means and control apertures in combination with said diaphragm means accommodating selective flexing of the lips from a tightly closed to an open position in either direction only when either of first and second predetermined physiological liquid pressure differential thresholds is exceeded, the first solid wall means distal of the diaphragm means controlling at least in part the flex and setting one physiological liquid pressure differential required to open the slit in a distal direction at a relatively low differential value and the second solid wall means proximal of the diaphragm means controlling at least in part the flex and setting the pressure differential required to open the slit in a proximal direction at a relatively high differential value.

12. Two-way physiological valve structure for disposition external of a body of a medical patient, the valve structure comprising:

housing means comprising proximal physiological liquid ingress and egress flow port means, distal physiological liquid ingress and egress flow port means and a hollow interior defining a single flow path along which physiological liquid entering the port means selectively flows in a desired direction;

bi-directional displaceable, pressure-responsive slit valve means transversely disposed within the hollow interior of the housing means and comprising peripheral means imperviously secured at the housing means, the slit valve means further comprising normally closed slit means with memory comprising opposed lips with contiguous opposed edge held sealingly and alignedly together by said memory only when physiological liquid pressure differential across the slit valve means is within a predetermined range, the edges separating to open the slit valve means only when physiological liquid differential pressure is above or below the predetermined range to accommodate proximal and distal liquid flow respectively along the single flow path in a single direction during liquid egress flow and in the opposite direction during liquid ingress flow;

means apertured only at the center thereof contiguously associated with slit valve means and also imperviously secured at the housing means for selectively determining in combination with said slit valve means said predetermined range, said range determining means comprising a central aperture and being contiguously juxtaposed said slit valve means adjacent to said central aperture.

13. Valve structure according to claim 12 wherein the slit means comprise an elastomeric diaphragm comprising at least one slit, the diaphragm being flexed to separate the lip edges only when the physiological liquid pressure differential is above and below the range.

14. Valve structure according to claim 13, wherein the diaphragm is flat and of generally uniform thickness.

15. Valve structure according to claim 13 wherein the diaphragm comprises an elastomeric disc.

16. Valve structure according to claim 13 wherein the diaphragm is rectangularly shaped.

17. Valve structure according to claim 12 wherein the housing means comprise at least two parts and releasible fastening means holding the two parts together.

18. Valve structure according to claim 17 wherein the two parts are fastened together by threaded connectors.

19. A cardiovascular assembly comprising:

first tubing means comprising a hollow interior for placement, at a distal end thereof, in a cardiovascular system of a patient;

a source of liquid disposed external of and above the patient by which a first always positive liquid pressure caused at least in part by gravity is created in the assembly and from which an essentially uncontaminated flow of the liquid is provided directly to the patient without human manipulation;

second tubing means comprising a hollow interior and distal and proximal ends disposed external of the patient, the hollow interior of the second tubing means at the proximal end being in direct communication with the source liquid at the first liquid pressure;

two-way valve structure without selectively settable parts contiguously and directly interposed between the distal end of the second tubing means and the first tubing means at a proximal end thereof external of the patient, a proximal part of the two-way valve structure being in direct communication with the interior of the second tubing means at the distal end thereof, the source liquid therein and the first liquid pressure and a distal part of the two-way valve structure being only and directly in communication with the hollow interior of the first tubing means at a proximal end thereof and a second cardiovascular pressure therein when said first tubing means are disposed in liquid communication with the cardiovascular system of the patient;

the second tubing means further comprising means for selectively applying a third pressure across said two-way valve structure; and

the two-way valve structure comprising centrally interior normally closed bi-directionally pressure-responsive slit valve means, the slit valve means being imperviously secure at its periphery and selectively accommodating only unidirectional flow of a predetermined quantity of liquid across the valve structure directly between the first and second tubing means only directly along selectively openable/closeable centrally disposed flow path means only in a proximal to distal direction flow of said predetermined quantity of liquid to the patient without human manipulation only when the first pressure exceeds the second by a predetermined magnitude and the third pressure is not being imposed, flow in a distal to proximal direction across the two-way valve structure only when the third pressure controls and reaches a predetermined amount.

20. An assembly according to claim 19 wherein the slit valve means comprise an elastomeric diaphragm and the centrally disposed flow path means comprise a central slit having opposed lips whereby the lips of the slit are flexed open in either direction only when the difference in the first and second pressures is above a predetermined threshold value.

21. An assembly according to claim 20 wherein the diaphragm comprises an elastomeric disc.

22. An assembly according to claim 20 wherein the diaphragm is rectangularly shaped.

23. An assembly according to claim 19 wherein the two-way valve structure comprises hollow housing means comprising means which imperviously secure the slit valve means at the periphery thereof.

24. An assembly according to claim 23 wherein the hollow housing means comprise at least two parts fastened together.