ETCO₂ waveform demonstrating effects of phrenic nerve pacing

Leads II and V5 on the ECG are shown in green. The spike in the ECG (arrow) is representative of stimuli from phrenic nerve pacing. The capnogram is shown in white, with alterations in the ETCO₂ curve due to diaphragmatic contraction occurring with phrenic nerve pacing (circle). Note that the capnogram tracing speed is slower than the standard sweep speed of the ECG and SpO₂ tracing. The plethysmogram from the pulse oximeter is shown in green and represents the SpO₂ value.