An acoustic sensor attached to a medical patient can non-invasively detect acoustic vibrations indicative of physiological parameters of the medical patient and produce an acoustic signal corresponding to the acoustic vibrations. The acoustic signal can be integrated one or more times with respect to time, and a physiological monitoring system can determine pulse or respiration parameters based on the integrated acoustic signal. The physiological monitoring system can, for instance, estimate a pulse rate according to pulses in the integrated acoustic signal and a respiration rate according to a modulation of the integrated acoustic signal, among other parameters. Further, the physiological monitoring system can compare the integrated acoustic signal or parameters determined based on the integrated acoustic signal with other signals or parameters to activate alarms.