At commencement of CPB it was noted that gas exchange was impaired. (Patency of gas flow had been checked prior to CPB).
Patient weaned from CPB and ventilated whilst issue investigated. Found gas flow into vapourizer ok, butoutflow from vaporizer minimal. Vapourizer removed from the gas circuit and CPB recommenced with no further problem (patient given propofol for anaesthesia).
None
GE Tec 7
Vaporizer removed from service and checked by GE-no problem found, but remains out of service and will be replaced. Selectatec bar that vapourizer mounted on also taken out of service and replaced (unclear which of these parts is at fault as testing produces variable results). Addition to pre-CPB checklist to check patency of gas flow with vapourizer on as well as off.