During the calibration of a transcutaneous electrode, the signal is found to be drifting. Which of the following is the most appropriate action to take?

a. Move the electrode to another site.
b. Increase the temperature of the electrode.
c. Clean off the silver deposit on the cath-ode.
d. Change the electrolyte and the sensor membrane.

ANS: D
The electrolyte and the sensor's membrane should be checked regularly and changed weekly or whenever a signal drift during calibration is noticed.