EKG/ECG and SPO2 cables require cleaning but never use rubbing alcohol or peroxide to clean them!
Alcohol will dry out and penetrate the cable covering (vinyl-rubber-silicone) and in a short time the covering will harden and crack allowing air to penetrate the ribbon-like wire inside. Eventually this wire will rust and break.
Use a mild soap solution (non-abrasive) and water on the cables.
Clean the EKG/ECG connection clip or electrode with white toothpaste.
Be sure to dry the equipment to prevent potential corrosion.
TIP: To prevent EKG/ECG wire contamination, cover the cable (but not the connection point) with plastic wrap (like Saran Wrap). For SPO2 cables, cover the entire cable and connector with plastic wrap making sure the connection point to the animal has no more than one layer of plastic wrap.