A medical device suitable for assisting in liquid proof shielding of a catheter application area on the body of a living creature is described. The device comprises a base element tightly placeable on a body area near the catheter application area, and a top element connectable with the base element. One of the base element or the top element is an element comprising a slit for holding a catheter tube or infusion line and the other element comprising a protrusion for closing the slit and for forming a feedthrough for the catheter when the elements are connected. A first portion for tightly fitting and a second portion for forming a liquid sealing element for the catheter is used.
