Abstract: An insertion site for a cannula (23) on a skin (8) of a patient is prepared by applying a skin cover unit (1) of the type comprising a window (2) and a wall (3) in extension of the window (2) and connected to the window (2) by a bending region (4) for bending the wall (3) into an angled orientation relatively to the window (2); wherein the win-dow (2) comprises a stabilizing frame (5) and an ultrasonic-transparent flexible sheet (6) within the frame (5). The flexible sheet (6) is glued onto the skin (8) of the patient for ultrasonic investigation of the insertion site through the flexible sheet (6). By bending the bending region (4), the angular orientation of the wall (3) is adjusted into an approximately perpendicular orientation relatively to the window (2) for separating the insertion site from the flexible sheet (6) by the wall (3).

Abstract: A cover unit for inserting a puncture device such as a cannula in an anatomical structure such as a vein or an artery and for maintaining said puncture device in said anatomical structure, comprising a flexible film having a glue provided surface, and a removable covering layer to cover said glue provided surface, wherein said cover unit comprises a patient adherent member and a barrier member connected along a connection line, which is arranged close to a puncture site in a patient; said film being made of an ultrasound transparent material; said barrier member being provided with at least one slit or weakening line extending from next to said connection line to a side edge of the cover unit and provided in said film; and said covering layer in the barrier member is removable from the film separately from the corresponding covering layer in the patient adherent member.

Abstract: A cover unit for inserting a puncture device such as a cannula in an anatomical structure such as a vein or an artery and for maintaining said puncture device in said anatomical structure, comprising a flexible film having a glue provided surface, and a removable covering layer to cover said glue provided surface, wherein said cover unit comprises a patient adherent member and a barrier member connected along a connection line, which is arranged close to a puncture site in a patient; said film being made of an ultrasound transparent material; said barrier member being provided with at least one slit or weakening line extending from next to said connection line to a side edge of the cover unit and provided in said film; and said covering layer in the barrier member is removable from the film separately from the corresponding covering layer in the patient adherent member.