PROBLEM TO BE SOLVED: To provide a circulating smoke exhaustion system capable of exhausting smoke without causing variation in the abdominal cavity pressure even when a sheath is removed from the body cavity.SOLUTION: The circulating smoke exhaustion system comprises: a circulation apparatus 2 for exhausting smoke produced within a body cavity of a patient 14 together with carbon dioxide gas in a circulating manner； a trocar 12b one end of which is pierced into an abdominal wall of the patient 14 and which has a check valve provided on the proximal side； a trocar 12c one end of which is pierced into an abdominal wall of the patient 14 and which has a check valve provided on the proximal side； a sheath 13b which is mounted to an endoscope 10 inserted through the trocar 12b, and which sends carbon dioxide gas and/or a sheath 13c which is mounted to an electrode knife 11 inserted through the trocar 12c, and which sucks carbon dioxide gas； and a processor 5 which detects whether or not the sheaths 13c, 13c are inserted into the trocar 12b and/or the trocar 12c, and which controls the operation of the circulation apparatus 2 based on the detection result.SELECTED DRAWING: Figure 1【課題】シースが体腔内から抜けた場合にも、腹腔圧を変動させることなく排煙することができる、循環排煙システムを提供する。【解決手段】循環排煙システムは、患者１４の体腔内で発生した煙を炭酸ガスとともに吸引し循環排煙する循環装置２と、一端が患者１４の腹壁に刺入され基端側に逆止弁が設けられたトラカール１２ｂと、一端が患者１４の腹壁に刺入され基端側に逆止弁が設けられたトラカール１２ｃと、トラカール１２ｂに挿通される内視鏡１０に装着され炭酸ガスを送気するシース１３ｂ、及び／又は、トラカール１２ｃに挿通される電気メス１１に装着され炭酸ガスを吸引するシース１３ｃと、シース１３ｃ、１３ｃがトラカール１２ｂ、及び／又は、トラカール１２ｃに挿入されているか否かを検知し、検知結果に基づき循環装置２の動作を制御するプロセッサ５と、を有する。【選択図】図１
