Endotracheal tube having a relief valve

Claim 1

An endotracheal tube comprising: a tubular member having a proximate and a distal end and a first lumen passing therethrough between said proximate and distal ends; an inflatable low pressure sleeve attached to said tubular member; an auxiliary tube member having a first open end, a second open end and a second lumen passing therethrough between the first and second open ends, said first open end communicating with said inflatable low pressure sleeve; a hollow body having continuous passage therethrough between a third open end and a fourth open end, said third open end communicating with said second open end of said auxiliary tube member; non-return valve means connected to said hollow body in said fourth open end for allowing inflation of the low pressure sleeve through said fourth open end, said hollow body and second lumen and for preventing deflation of said low pressure sleeve through said fourth open end; and relief valve means for allowing the deflation of said low pressure sleeve to a defined pressure when the pressure within said low pressure sleeve exceeds the defined pressure, said relief valve means including said hollow body being provided with an opening between said third and fourth open ends and an elastic tubular skin means, said skin means being substantially wider than said opening and being stretched around the outside of said hollow body for sealing said opening in the hollow body when the pressure within the pressure sleeve is below a defined pressure, for lifting away from the hollow body and allowing deflation of the low pressure sleeve to the defined pressure when said pressure in the low pressure sleeve exceeds the defined pressure and for providing resilient means for preventing deflation of the low pressure sleeve to a pressure below the defined pressure by resealing itself over the opening when the pressure in said low pressure sleeve is reduced to the defined pressure, whereby the pressure within said low pressure sleeve is maintained at the defined pressure.