How is an intraoperative air embolism detected and managed on CPB?

• A. Detected by bubble detectors and reservoir changes; flooded field, aspirating air from lines, and deairing
• B. Detected by EKG changes; managed by flooding the field
• C. Not detectable
• D. Managed by diuretics

Answer: (A)

Air embolism on CPB is detected and managed by directly addressing the bubbles in the circuit. Bubble detectors placed in the CPB circuit (in the oxygenator and lines) will sense microbubbles, and changes in the venous reservoir level signal gas entering the system. When bubbles are detected, the team works to prevent more air from entering the circuit by flooding the surgical field, then actively removes air by aspirating it from cannulas and circuit lines, and performing deairing maneuvers to eliminate air from the circuit and the heart (using vents and other deairing techniques). EKG changes are not a reliable primary detection method for this scenario, and diuretics do not address the presence of intravascular air.