An electronic sensor patch includes a capacitive sensor configured to detect when the electronic sensor patch is applied to a patient. A processor may be powered down for a predetermined time interval in response to determining that the electronic patch is not in close proximity to a body. The electronic sensor patch may be activated in response to determining that the electronic patch is in close proximity to the body. The capacitance sensor may be used to determine whether the electronic sensor patch is in close proximity to a body by measuring capacitance of the capacitance sensor, comparing the measured capacitance to a threshold, and determining that the electronic sensor patch is in close proximity to a body in response to the measured capacitance of the capacitance sensor being more than the threshold.