Process for treatment of ascites and device to accomplish same

Abstract

A method for the transfer of body fluid which accumulates in the peritoneal cavity into the vascular system is disclosed. This accumulation occurs most frequently with patients suffering from cirrhosis of the liver and constitutes a lethal complication. An implant device is disclosed which comprises a plastic chamber and connecting tubing, said chamber containing unique valve structure comprising a flexible diaphragm seated on a shoulder and attached to this diaphragm a connector bar which is attached at its other end to the center plate of a structure composed of several lateral silicone rubber struts which radiate out from the center plate to connect to a circular peripheral ring. The circular peripheral ring is anchored fixedly to the lateral wall of the valve housing by compression between two threaded connectors of plastic also. These rubber struts place pressure constantly on the diaphragm pulling it toward the shoulder which closes the valve. The diaphragm member is thus fixed to the side wall of the valve housing by the elastomeric strut members. The seat of the diaphragm valve is adjustable and hence it can control the fluid pressure required to open the valve.

Description

BACKGROUND OF THE INVENTION

Ascites is a serious medical malady characterized by an accumulation of body fluid in the peritoneal cavity. Acitic fluid as it is called accumulates most frequently with patients who have cirrhosis and unless corrected can cause death. This fluid which accumulates is rich in body building protein and unless recovered the patient suffers from wasting malnutrition.

There is no known adequate therapy at present to induce readsorption or excretion of the ascitic fluid once it is generated. Diuretic therapy and restriction of the patient's salt intake can slow the accumulation of fluid but can do nothing about recovery of the fluid or removal from the body once it is formed. Under current techniques the only means employed in such cases is repeated paraceutesis to empty the peritoneal cavity of its accumulated fluid. But abviously this induces a loss of the fluid and its valuable body proteins.

A second clinical situation in which an abnormal amount of fluid collects in the body cavity is hydrocephalus. In this condition fluid accumulation occurs in a ventricle of the brain and the excess of fluid tends to compress the brain tissue.

Ideally both of these fluids should be returned to the circulating blood stream or in the case of the hydrocephalic fluid to the peritoneal cavity where it is not so great in quantity that unlike the acitic fluid it can be absorbed by the tissue. The aforesaid device and method of its use makes both fluid transfer objectives attainable and comprise the subject matter of this invention as will be described in elaborate detail below.

BRIEF DESCRIPTION OF THE INVENTION

A device is described which can be permanently implanted into the human body and employed as a one way valve so that accumulated acitic fluid can be drained through a silicone rubber tubing from the peritoneal cavity into the blood stream without danger of the blood leaking back in the tube from the circulation into the peritoneum.

The valve mechanism and structure of my device has been designed to meet certain requirements. First it must be positive in action and the closure of the valve cannot depend upon flow of fluid alone because low flow rates may not be sufficient to close the valve when required. Significantly the reverse flow of even a small amount of blood from the circulation into the silicone tubing would clog the tubing since the blood would undergo thrombosis.

Second therefore the valve must normally be in a closed position and differential pressure must be employed as the actuating means to cause the valve to open and close. In practice a pressure differential of at least one or two centimeters of H.sub.2 0 must exist between the venous and peritoneal fluid pressures before the valve will open and permit the peritoneal fluid to flow into the venous system. When this pressure differential disappears the valve closes.

The aforesaid mode of operation acts as a safeguard against back flow of blood and consequent thrombosis of the conduit. In addition this also slows down the delivery of fluid as the venous pressure of the receiving system rises. This prevents a sudden overloading of the circulatory system with acitic fluid. Collaterally, a normally closed valve allows the fluid accumulation to be maintained at a pressure above the venous pressure. This latter attribute is particularly important in relief of hydrocephalis where the reduction of the ventricular pressure to very low levels causes sagging of the brain tissue.

The device of the invention has a valve structure constructed of inert plastic and silicone rubber both of which materials are compatible with tissue. The device will be further described by reference to the

FIG. 1 of the attached drawing of a cross sectional view of the device and

FIG. 2 which is an exploded view.

In the drawing FIG. 1 it can be seen that the device comprises a plastic housing 1 which contains an inlet tube 2 coming from the peritoneum and an outlet tube 3 going into the jugular or some other large vein. Inside the plastic housing a molded lip 16 extends out from the interior of the housing wall at the end proximate to the inlet 2 and its extension forms a circular valve seat 4. A silicone rubber inverted cup structure comprises the valve disphragm 5. The valve diaphragm has a central connecting bar 6 which attaches at its opposite end to a wheel like arrangement which acts as a support means for the valve. The central connecting bar 6 attaches to a center plate 7 which has several radiating struts 8 which extend out from the central plate to a peripheral support ring 9 which fits compressively into an attachment groove or slot 10 in the wall of the housing 1. The support ring 9 is held compressively in the groove 10 by an interior threaded connector 11 which has also an attachment shoulder 12 in the wall of the housing to attach tubing which shoulder is located distal to the fluid inlet 13 which introduces the ascites fluid into the valve chamber.

After the fluid from the peritoneum enters the fluid inlet 13 which is usually a polyethylene tubing it passes into the inlet tube 2 which emptys it into an inlet reservoir 14. When the fluid pressure in the inlet reservoir 14 builds up to a significant level it forces the upward movement of the connecting bar 6 and diaphragm 5 because of the fluid pressure exerted on the center plate 7 by the fluid collected in the fluid actuating column 17. Since the circular peripheral ring 9 is fixed in its position the upward movement of the central valve bar 6 causes the diaphragm 5 to move upward and out of its valve seat 4 and permits the fluid to flow in column 17 under the diaphragm 5 and around the same into a central collecting cavity 18 from where the fluid passes through the opening 19 which appear between the radial struts 8 of the support wheel. From there the fluid passes into the outlet reservoir and into the outlet tube and into the fluid outlet 20 which is polyethylene tube which is inserted into a large jugular vein or other large artery for passage of the fluid into the vascular system.

Continuing with the description of the operation of the device and still refering to FIGS. 1 and 2 it should be noted that the passage of fluid through the valve halts when the pressure against the valve created by the inlet fluid drops below a certain level. This causes the diaphragm 5 to return to its abutment against the valve seat 4 and once again closes the valve.

While the aforesaid disclosure will certainly suggest to those reading the same many variations in structure of the same it is applicants intention to claim the concept which is essentially defined in the following claims.

Claims

I claim as my invention:

1. I claim a method for the transfer of body fluids which accumulates in the peritoneum cavity and into the vascular system which comprises passing fluid through a connecting tube into the inlet chamber of a hollow plastic implanted valve, causing that valve to open and passing the fluid under pressure into a second reservoir from where the fluid is conducted through a second section of tubing which tubing is connected to the jugular vein of the patient.

2. A device for use in the method of claim 1 which comprises a plastic housing having connected on opposing surfaces, thereof an inlet tube and an outlet tube respectively said inlet tube opening on one end into the peritoneum and on the other end into an inlet reservoir located within said housing, said reservoir having a pressure movable wall which comprises a flexible diaphragm which rests against a valve seat and which diaphragm moves away from said valve seat in response to pressure exerted thereon to permit flow of the body fluid from the peritoneum through the valve housing and into the outlet tube and jugular vein.

3. A device according to claim 2 wherein said pressure movable wall comprises the shape of an inverted cup and said cup is connected to a permanently attached valve support member.