Patent ID: 8460189

Claim:
A method of monitoring an ambulatory patient with a monitoring system, the method comprising: adhering an adherent device to a skin of the patient, the adherent device comprising an accelerometer and at least two physiological measurement electrodes, the accelerometer comprising three orthogonal measurement vectors in a three-dimensional coordinate system XYZ and wherein each of the three orthogonal measurement vectors extends along one of the coordinate system's axes, and the at least two physiological measurement electrodes configured for measuring physiological parameters, the at least two electrodes being separated by a distance to define an electrode physiological measurement axis; measuring an accelerometer signal when the device is adhered to the patient standing or sitting upright wherein the accelerometer's axes are aligned/oriented with respect to the axes of the patient, and wherein the at least one accelerometer measurement axis is oriented with respect to the electrode measurement axis in a predetermined configuration; determining a vertical reference axis of the patient that extends vertically along the patient when the patient is standing or sitting upright, the vertical reference axis of the patient being transverse to the at least one accelerometer measurement axis; measuring an orientation of the electrode physiological measurement axis on the patient, the orientation corresponding to an inclination angle between the vertical reference axis and the electrode physiological measurement axis; and measuring physiological parameters of the patient with the at least two measurement electrodes after determining the orientation of the electrode physiological measurement axis and modifying the physiological parameter measurements with the system based on the measured orientation so as to minimize errors in the physiological parameter measurements associated with the inclination angle between the electrode measurement axis and the vertical reference axis of the patient.