Question: When our anesthesiologists begin a bypass case without the pump oxygenator, then they switch to on-pump for the last hour, what is the correct way to code this? Montana Subscriber Answer: Traditional open-heart surgery cases begin without the pump oxygenator and move to on-pump — the surgeon makes a large incision in the chest and, once the heart is exposed, inserts tubes into the heart so that the blood can be pumped through the body by a heart-lung bypass machine while the heart is stopped. You typically report these with 00567 (Anesthesia for direct coronary artery bypass grafting; with pump oxygenator) unless the procedure is a reoperation within a month of the original bypass. In that case, report code 00562 (Anesthesia for procedures on heart, pericardial sac, and great vessels of chest; with pump oxygenator, age 1 year or older, for all noncoronary bypass procedures (eg, valve procedures) or for re-operation for coronary bypass more than 1 month after original operation). Tip: Remember anesthesia coronary artery bypass graft (CABG) codes 00561 (Anesthesia for procedures on heart, pericardial sac, and great vessels of chest; with pump oxygenator, younger than 1 year of age) through 00563 (Anesthesia for procedures on heart, pericardial sac, and great vessels of chest; with pump oxygenator with hypothermic circulatory arrest) and 00567 include the total body hypothermia and controlled hypotension services represented by add-on codes +99116 (Anesthesia complicated by utilization of total body hypothermia …) and +99135 (Anesthesia complicated by utilization of controlled hypotension …). Thus, you don’t want to include these qualifying circumstance codes on your claim. Working on a beating heart carries a greater risk. If the bypass is performed without a pump oxygenator (known as an off-pump bypass graft), report 00566 (Anesthesia for direct coronary artery bypass grafting; without pump oxygenator).