Abstract: Apparatus for monitoring respiration and heartbeat and for processing electrical signals representative thereof, including circuits for developing a phase-shifted and amplitude-offset respiration signal for comparison with an original respiration signal for compensating for signal drift, and circuits for logically combining signals representative of the presence of respiration and heartbeat for eliminating certain false indications which may occur when only heartbeat exists.

Abstract: A blood pressure monitoring system is disclosed as comprising a pressure transducer coupled as by a catheter inserted into the blood vessels of a patient whose blood pressure is to be measured, for providing an output signal indicative of the patient's blood pressure, a filter for removing undesired high-frequency components imposed upon the transducer output, a maximum peak detector, a minimum peak detector and a mean detector for providing outputs indicative respectively of the systolic blood pressure, the diastolic blood pressure and the mean blood pressure of the patient.

Abstract: A blood pressure monitoring system is disclosed as comprising a pressure transducer coupled as by a catheter inserted into the blood vessels of a patient whose blood pressure is to be measured, for providing an output signal indicative of the patient's blood pressure, a filter for removing undesired high frequency components imposed upon the transducer output, a maximum peak detector, a minimum peak detector and a mean detector for providing outputs indicative respectively of the systolic blood pressure, the diastolic blood pressure and the mean blood pressure of the patient. Depending upon the desired indication, the output of one of the aforementioned detectors is coupled by a switch to a processing circuit for applying an output indicative of the patient's blood pressure for a selected period of time to a digital display.