Abstract: A catheter having a body made from elastomeric material and including a tubular inner part defining a fluid passageway having an inlet end and an outlet end. A tubular outer retention sleeve integrally connected only at the inlet end to the inner part extends in the direction of the outlet end in axially surrounding relation to the inner part. The retention sleeve is biased to a normal retention configuration for engaging the peripheral wall of an associated body passageway to releasably retain the catheter in preselected position therein and is stretchable to an insertion configuration to permit the catheter to be freely inserted into the body passageway and removed therefrom. A valve provides a closure for the outlet end. A frangible wall portion of the inner part between the inlet opening and the valve is constructed and arranged to rupture in response to predetermined fluid pressure within the passageway to vent fluid therefrom.