Systems and methods for detecting intrathecal penetration are disclosed. A method in accordance with one embodiment includes detecting a value corresponding to an impedance of an electrical circuit that in turn includes an electrical contact located within the patient, and patient tissue adjacent to the electrical contact. The method further includes comparing the detected value to a predetermined criterion, and, if the detected value meets the predetermined criterion, identifying penetration of the patient's dura based at least in part on the detected value.