A medical device system and associated method discriminating conditions that includes a plurality of sensors, a sensing module coupled to the plurality of sensors and configured to acquire signals from the plurality of sensors, and a processor coupled to the sensing module and configured to determine a change in a respiratory related sounds in response to a signal from a sensor of the plurality of sensors, select one or more sensors of the plurality of sensors associated with the determined change, determine a respiratory signature in response to signals from the selected one or more sensors, and determine the respiratory condition in response to the determined respiratory signature.