Preparation of Therapeutic Foam

Abstract

A device is described for facilitating the preparation of therapeutic foam e.g. for the treatment of varicose veins. A pressurised vial contains a sclerosant liquid, e.g., polidocanol solution, and a sterile gas which is readily absorbed by the body, e.g., carbon dioxide, oxygen or a mixture of these gases. The vial is provided either with a specialised stopper/seal into which a syringe nozzle may be inserted or alternatively a septum seal which may be penetrated by a hypodermic needle. The quantities of gas and liquid and the pressure in the vial are pre-set so that, on connection of a syringe to the vial, a predetermined volume of both gas and liquid is transferred to the syringe, with the intention that the syringe is then used to make a foam by known means. The use of the vial ensures that the ratio of gas to liquid in the foam is standardized, and also provides a convenient way of packaging the gas and liquid and of filling the syringe in a sterile manner.

1 . A vessel having sterile contents, the contents comprising in predetermined proportions (i) a foamable liquid and (ii) a gas or gas mixture other than air, the contents being at a pressure substantially above atmospheric, the vessel having an outlet adapted to cooperate with a syringe nozzle, the said outlet having associated with it a breakable seal or a valve. 
   
   
       2 . A vessel as claimed in  claim 1  wherein the said breakable seal or valve is adapted to be opened by the action of inserting a syringe nozzle. 
   
   
       3 . A vessel as claimed in  claim 1  wherein the pressure of the contents is 1.3 bara or more, preferably 1.5 bara or more. 
   
   
       4 . A vessel as claimed in  claim 1  wherein the gas or gas mixture consists substantially of oxygen, carbon dioxide or a mixture thereof. 
   
   
       5 . A vessel as claimed in  claim 1  wherein the foamable liquid is sclerosant liquid solution. 
   
   
       6 . A vessel as claimed in  claim 5  wherein the foamable liquid is a solution of polidocanol. 
   
   
       7 . A vessel having substantially sterile contents comprising in predetermined proportions (i) a foamable liquid and (ii) a gas or gas mixture other than air, the contents being at a pressure substantially above atmospheric, the vessel having a resilient closure such as a rubber septum which is piercable by a hypodermic needle or similar, and which forms a seal around the needle when it is pierced. 
   
   
       8 . A vessel as claimed in  claim 7  wherein the septum has substantial thickness, e.g., between 2 and 10 mm. 
   
   
       9 . A vessel as claimed in  claim 7  wherein the pressure of the contents is 1.3 bara or more, preferably 1.5 bara or more. 
   
   
       10 . A vessel as claimed in  claim 7  wherein the gas or gas mixture consists substantially of oxygen, carbon dioxide or a mixture thereof. 
   
   
       11 . A vessel as claimed in  claim 7  wherein the foamable liquid is a sclerosant liquid solution. 
   
   
       12 . A vessel as claimed in  claim 11  wherein the foamable liquid is a solution of polidocanol.