Ambulatory patient monitoring apparatus including a portable housing including at least one physiological data input device operative to gather physiological data of the patient, location determination circuitry, and communications circuitry for communicating the physiological data and the geographic location information to a central health monitoring station wirelessly and over a data network, and control circuitry operative to simultaneously store a first portion of such physiological data in a memory in FIFO fashion and a second portion of such physiological data in such memory that is write-protected with respect to said first portion.