Background: Carbon dioxide (CO2) embolism is a rare but potentially life-threatening complication of endoscopic surgery. While endoscopic thyroidectomy is superior to traditional open thyroidectomy in terms of cosmetic results, it may lead to venous or fatal paradoxical CO2 embolism. CO2 embolism involves the inadvertent injection of carbon dioxide into a large vein, artery, or solid organ. The clinical manifestations of CO2 embolism can vary from asymptomatic to neurological damage, cardiac failure, and even death, depending on the rate and volume of CO2 entry and the patient’s general condition. This case can enhance our understanding of CO2 embolization during endoscopic surgery. Case Presentation: This case report describes an incident in which a gas embolism occurred during endoscopic right lobe and isthmus thyroidectomy, resulting in arrhythmia and dramatic fluctuations in circulation and oxygen levels. The operation was halted, and CO2 injection was stopped. The surgical wound was covered with saline gauze, and the patient inhaled 100% pure oxygen while undergoing aggressive repeated manual pulmonary recruitment maneuvers. Additionally, vasoactive drugs such as m-hydroxyamine and ephedrine were administered to aid in treating the condition. The patient’s position was adjusted using the Durant maneuver (partial left lateral and Trendelenburg position). Following the aforementioned treatments, the patient’s ventricular arrhythmia transitioned back to a normal and regular sinus rhythm, and both circulation and oxygen levels stabilized. Conclusions: Carbon dioxide embolism is an uncommon yet potentially severe complication of laparoscopic procedures. We anticipate that this particular case will enhance our comprehension of carbon dioxide embolism during endoscopic surgery.