An improved vessel for perfusion liquids

Abstract: The vessel (1) for perfusion liquids of the type which is closed at one extremity (4) and having a filling orifice (6) at the other (5) with a zone (8) for the insertion of a syringe or abstraction needle of the catheter supply tube, the vessel (1) being characterized by having incorporated therein integrally and inviolably a microfilter (7) for wet filtration preventing the passage of air under atmospheric pressure and permitting its correct functioning without dismantling the sterilized assembly.

Description: This invention refers to an improved vessel for containing perfusion liquids offering important novel characteristics in its utilization with respect to currently known vessels used for this purpose. Perfusion liquid containers are used generally for the various types of fluids destined for perfusion or injection in the human body, their particular requirement being that they should contain the said fluid under sterile conditions which condition must be maintained up to the moment of the application of the fluid in a clinical operation. Current practice is to sterilize the vessel which already contains the fluid for therapeutic use should the fluid be able to tolerate this procedure or in the contrary case, to sterilize the vessel prior to its filling and then carry out the filling operation in a sterile enclosure so as to preserve the required sterile condition of the fluid to be fed into the vessel and that of the vessel itself. However, there have been proposed improved perfusion liquid vessels having important advantages as against existing containers in that the requirement for sterile enclosures for sterilizing the liquid to be contained in the vessel is no longer necessary (or even in the absence of this requirement ), sterility is maintained up to the moment of use and an automatic control system can be applied to ensure that the procedure has been correct. A perfusion liquid vessel of this improved type is disclosed in, e.g. EP-A-0 116 362, having a flattened form, closed at one extremity and having connected to the other extremity a filling tube with a microfilter integrally formed therein for filling the vessel with a perfusion liquid, whereby the microfilter, when still in wet condition after a perfusion liquid has been filled into the vessel, prevents the passage of air under atmospheric pressure and permits its correct functioning to be verified by a bubble point test, and the vessel having also a zone where a syringe or abstraction needle of a catheter feed tube can be inserted. However, the filling tube and the zone where the syringe can be inserted are located apart from each other at opposite ends of the vessel. US-A-4 265 242, US-A-4 265 760, DE-A-33 33 283 and WO-A-92/12697 disclose similar perfusion liquid vessels. It is the object of the invention to provide a liquid perfusion vessel as is known from EP-A-0 116 362 with a simplified bag structure and a more economical production. This object is solved by providing the vessel at its upper extremity with a detachable element having a first tubular body and essentially parallel thereto a second tubular body, the first tubular body accomodating the filling tube protruding therefrom and the second tubular body forming the zone where the syringe or abstraction needle can be inserted and having at some intermediate position a thin diaphragm and at its upper extremity a manually operable closure tab. Essentially, the vessel which is the object of this invention has built therein a tube for filling the vessel and which tube has integral with it and inalienable thereto a sterilizing membrane filter with a porosity of between 0,20 and 0,25 microns, for preference being 0,22 microns maximum, such that filling the vessel is coincident with a sterilization action and then, having filled the vessel, given the considerable capilliary force exercised in passages of this fineness, air flow is prevented unless the pressure attains some 3 bars, this phenomenum permitting verification and eventually the integrity and correct operation of the filter. This effect facilitates the control of the filter's correct operation since due to the surface tension in the fine passages of the filter the above pressure is required to overcome this tension and allow air to infiltrate the vessel. Hence after the operation of filling the vessel, in order to check the filter effectiveness an air pressure is applied equivalent to the surface tension produced in the filter and at that point no bubbles should be observed forming in the vessel. This bubble point, measured by the air pressure that the filter is resisting presents a simple method for determining the integrity of filter itself. To assist the explanation explanatory drawings are attached showing one embodiment, by way of example, of a liquid perfusion vessel in accordance with this present invention. Figure 1 shows a frontal view of the vessel in its vertical position. Figure 2 is a cross sectional view on the plane so indicated in figure 1. Figure 3 shows the detail of the filling tube assembly with its incorporated filter in cross-section. Figure 4 is a cross sectional view on the plane so indicated in figure 3. Figure 5 is a cross sectional view on the plane so indicated in figure 3. As can be seen in the drawings this invention comprises a vessel -1-, made of a synthetic material that is clinically compatible having a flattened form generally, the front and rear faces -2- and -3- respectively being generally planar with the upper -5- and lower zones -4-being formed with half round or similar ribbing or projections so as to provide an adequate stiffness and strength to those areas. The upper zone -5- has incorporated therein the filling tube -6- with the sterilization filter -7- in its upper part, integral with it and forming part of the inviolable system of a non-detachable assembly. The filter has a porosity of between 0,20 and 0,25 microns, but preferably not exceeding 0,22 microns such that the vessel can be filled with the perfusion fluid through the tube -6- while the fluid's passage through the filter -7- effects its sterilization and thereafter this same filter with its above dimensioned pores operates as a stopper or closure in that for air to infiltrate through it a pressure of some 3 bars would have to be applied, this feature also providing an effective control by which the sterilizing characteristic of the filter may be monitored. The vessel is provided with an access tube -8- parallel to the filling tube incorporating a thin diaphragm -9- which can be perforated by the needle of the perfusion catheter feed tube. There is also fitted to the upper part of the orifice -8- a further stopper or plug -10- with a tab -11- attached thereto to facilitate its opening but ensuring its closure until the time of its utilization. Figure 3 shows the filter -7- as having two flat components -12- and -13- joined together by welding or pressing, the piece -13- having as part of it the filler tube -14- and the piece -12- being extended by a tubular connection -15- for attachment by welding or adhesive to the upper end of the tubular component -6-. It is acceptable to fill the vessel -1- in surroundings which may not necessarily be sterilized thus simplifying the operation and lessening the cost thereof as well as increasing security. Nevertheless the sterilization both during and after filling is assured by the specific characteristics of the filter preventing the entry of any particles exceeding the dimensions as foreseen for the sterilization effect and at the same time providing an effective impediment to the entry of external air and permitting a monitoring of the filtration effectiveness.

Claims: A vessel (1) for filling with perfusion liquids, having a flattened form, closed at one extremity (4) and having connected to the other extremity a filling tube (6) with a microfilter (7) integrally formed therein for filling the vessel (1) with a perfusion liquid, whereby the micro-filter (7), when still in wet condition after a perfusion liquid has been filled into the vessel (1), prevents the passage of air under atmospheric pressure and permits its correct functioning to be verified by a bubble point test, and the vessel (1) having also a zone where a syringe or abstraction needle of a catheter feed tube can be inserted, characterized in that the vessel (1) is provided at its upper extremely (5) with a detachable element having a first tubular body and essentially parallel thereto a second tubular body, the first tubular body accomodating the filling tube (6) protruding therefrom and the second tubular body (8) forming the zone where the syringe or abstraction needle can be inserted and having at some intermediate position a thin diaphragm (9) and at its upper extremety a manually operable closure tab (10, 11). An improved vessel (1) for filling with perfusion liquids as claimed in claim 1 characterized in that the microfilter (7) has a porosity of approximately 0.20 to 0.25 microns. An improved vessel (1) for filling with perfusion liquids as claimed in claim 2 characterized by the microfilter (7) consisting of two plates (12, 13) mutually joined together with rounded or curved grooving on their mutually facing surfaces, one (13) of the pieces having a filling orifice and the other (14) a connecting member (15) joined to the filling tube (6) incorporated within the first tubular body of the detachable element by means of an adhesive or by welding. An improved vessel (1) for filling with perfusion liquids as claimed in any of claims 1 to 3 characterized in that its front and rear surfaces (2, 3) respectively are planar with upper and lower zones (4, 5) being formed with half round or similar ribbings or projections so as to provide stiffness and strength to those areas.

Inventors: GRIFOLS LUCAS VICTOR, GRIFOLS LUCAS, VICTOR
Applicants: GRIFOLS LUCAS VICTOR, GRIFOLS LUCAS, VICTOR
Application year: 1992
Main classification: A61J1
IPC codes: A61J1, A61M11