Carbon dioxide embolism during transanal total mesorectal excision (TaTME): two case reports

Transanal total mesorectal excision (TaTME), a new approach for rectal cancers, requires transanal carbon dioxide (CO2) high-flow insufflation to create a workplace. Two patients scheduled for TaTME experienced CO2 embolism during the anterior mesorectal dissection in contact with the prostate. CO2 embolism resulted in a sudden drop of end-tidal CO2, preceded by a short increase in one patient, and in oxygen desaturation. Hemodynamic alterations were minor. We report these two cases and discuss the pathophysiology of CO2 embolism and risk factors that promote CO2 embolism during TaTME to warn anesthetists of this serious complication, often unexpected and misdiagnosed.