SurgiVet Cardio Companion. The Cardio Companion is an oesophageal lead equipped with 4 stainless steel electrodes to monitor cardiac performance during anaesthesia. Monitors core body temperature (if monitor has temperature function). Compatible with all existing ECG monitors. Colour coded leads for monitoring animals of different sizes. The Cardio Companion protects the clips inside a specially designed box preventing them from being touched while in use. When the oesophageal ECG sensor is inserted into the oesophagus and positioned over the heart, the distal electrode localises behind the left ventricle and the middle electrode behind the left atrium. The fourth electrode provides more versatility by enabling you to handle any size patient. The proximal electrode functions as a ground. Select Lead II on your ECG monitor and observe the QRS waveform. Available in two sizes: Dog Medium Blue 18FR 105cm oesophageal lead or Exotics & Cats Small 12FR Green oesophageal lead. Available individually or in a set.