A method and medical device for adjusting a blanking period that includes sensing cardiac signals from a plurality of electrodes, the plurality of electrodes forming a plurality of sensing vectors, determining whether to adjust a blanking period during a first operating state, advancing from the first operating state to a second operating state in response to the sensed cardiac signals, determining, while in the second operating state, whether the blanking period was adjusted while in the first operating state, and adjusting the blanking period while in the second operating state in response to the blanking period being adjusted while in the first operating state.