What does the tracing contain if it features an unexpected shift in the baseline due to electrical interference?

The tracing associated with an unexpected shift in the baseline due to electrical interference is referred to as a wandering baseline. This term is used to describe variations in the baseline not attributed to the patient's physiological signals. When an electrical interference, such as from nearby electronic devices or poor contact with electrodes, disrupts the signal quality, it can cause the tracing to appear unstable or "wander." This can lead to difficulty in accurately interpreting the electrocardiogram (ECG) or other electrophysiological recordings.

In contrast, other terms such as somatic tremor refer specifically to movements of the patient themselves, like muscle tension or other bodily movements, while 60-cycle interference is a type of noise that occurs due to electrical sources operating at 60Hz, typically from the power supply. Artifact is a broader term that refers to any abnormal signal that is not a true representation of the physiological activity being measured, but a wandering baseline specifically describes a continuous drift of the baseline caused by external electrical factors.