The ornamental design for a patientmonitor, as shown and described.
FIG. 1 is a rear elevation view of an embodiment of the patient monitor showing our new design;
FIG. 2 is a front elevation view thereof;
FIG. 3 is a bottom plan view thereof;
FIG. 4 is a top plan view thereof;
FIG. 5 is a left side elevation view thereof; and,
FIG. 6 is a right side elevation view thereof.
The broken lines immediately adjacent the shaded areas represent the bounds of the claimed design, while all other broken lines are directed to environment and are for illustrative purposes only; the broken lines form no part of the claimed design.