Impact of sternotomy (A) and cardiopulmonary bypass (B) on gaseous ethylene. A: typical example of real-time monitoring of ethylene following initial diathermy (DT) for skin incision and sternotomy (ST). P, patient baseline; V, ventilation hold. B: example of real-time monitoring of ethylene at onset of CPB showing influence of changing fresh gas flow, temperature (T), rewarming, and aortic cross-clamp release (XC).