In this paper, a wireless system for remotely monitoring a patient's oxygen saturation (%SPO2), sphygmo (pulse) and plethysmogram levels is described. The data was continuously measured using a pulse oximeter and transferred to a central monitoring station via a IEEE 802.15.4 wireless sensor network for storage and display. MicaZ wireless motes were programmed with nesC and a graphical user interface was used to capture and display incoming measurements for all patients being monitored. Evaluation of the system was done based on the WSN performance criteria (packet loss and network lifetime) and also based on the accuracy of the collected medical data. In both respects the system performed very satisfactory and has been successfully implemented.