The ornamental design for a pulseoximeter, as shown and described.
FIG. 1 is a top, right, front perspective view of a pulse oximeter showing the new design;
FIG. 2 is a bottom, back, left perspective view thereof;
FIG. 3 is a front view thereof;
FIG. 4 is a back view thereof;
FIG. 5 is a side view thereof;
FIG. 6 is another side view thereof;
FIG. 7 is a top view thereof; and,
FIG. 8 is a bottom view thereof.
The broken lines illustrate portions of the pulse oximeter that form no part of the claimed design. The broken lines form no part of the claimed design.