The ornamental design for a medical dressing, as shown and described.
FIG. 1 is a top plan view of an ornamental design for a medical dressing in accordance with the present invention;
FIG. 2 is an enlarged top plan view of the upper left rounded corner of the medical dressing as shown in FIG. 1, where the medical dressing comprises two sheath layers that have a regular pattern of circular pores, the two layers are forming a shell formed by a surrounding welded seam, which exhibits a pattern of circular recessions, the two sheath layers form an outer rim surrounding the welded seam, the shell comprises an absorption body which is smaller than the shell so that there is a distance between the welded seam and the outer edge of the absorption body;
FIG. 3 is a further enlarged top plan view of the upper left rounded corner of the medical dressing as shown in FIG. 1;
FIG. 4 is a bottom plan view thereof in a folded condition;
FIG. 5 is a top plan view thereof in the folded condition;
FIG. 6 is a top plan view thereof in a partially folded condition; and,
FIG. 7 is an enlarged perspective view of the bottom right rounded corner of the medical dressing as shown in FIG. 1.