An ambulatory medical device that can communicate with a vehicle is described. An example of the ambulatory medical device includes one or more sensing electrodes configured to sense cardiopulmonary signals of a patient, a network interface, and one or more processors configured to receive signals from one or more vehicle occupancy sensors, detect usage of the ambulatory medical device in a vehicle based on the received signals from the one or more vehicle occupancy sensors, detect at least one of a medical event and a medical premonitory event of the patient based on the sensed cardiopulmonary signals, and provide driving control information to the vehicle, via the network interface, based at least in part on the detected usage of the ambulatory medical device in the vehicle and the detected medical event or medical premonitory event of the patient.
