Abstract: A patient arrhythmia monitoring system having a plurality of bedside stations that can derive physiological data for a patient coupled thereto, a central station, a bus for providing communication between said bedside stations and said central station. A processor is provided for analyzing the data from each station. Criteria for the indication of an alarm for a bedside station can be set at that station and at the central station. When an alarm is indicated for a bedside station, the data causing it can be viewed at that station as well as at the central station. Selected alarm data is temporarily stored by said processor in such manner that the data for any bedside station can be recalled at the bedside station from which it came and at the central station, A printer is provided for printing the selected alarm data for any bedside station on a separate page.

Abstract: Light of two different wavelengths is passed through or reflected from a member of the body so as to be modulated by the pulsatile blood flow therein. The amplitudes of the alternating current components of the logarithms of the respective light modulations are compared by taking their molecular extinction coefficients into account so as to yield the degree of oxygen saturation. By adding a third wavelength of light, the percentage of other absorbers in the blood stream such as a dye or carboxyhemoglobin can be measured. Fixed absorbers reduce the amount of light that passes through or is reflected from the body member by a constant amount and so have no effect on the amplitudes of the alternating current components that are used in making the measurements.

Abstract: A perfusion meter comprising a hand-held battery operated optical plethysmograph displays an indication of blood flow rate in response to the time-varying optical transmission characteristics of an ear or other organ. This indication, called the perfusion index, is proportional to both the amplitude and frequency of variations in the dynamic optical transmission characteristics of the ear or other organ.