Rapid identification of spontaneously resolving capnothorax using bedside M-mode ultrasonography during laparoscopic surgery: the "lung point" sign -two cases report-.

Pneumothorax during general anesthesia is more difficult to diagnose compared with that of non-anesthetized patient. Furthermore, the early diagnosis of pneumothorax is to some extent difficult due to CO2-pneumoperitoneum during laparoscopic surgery. The use of ultrasonography to diagnose pneumothorax has increased in a variety of situations, demonstrating a better diagnostic rate than conventional chest radiography. Here, we report two cases of intraoperative capnothorax that were confirmed using the M-mode "lung point" sign. However, the insertion of a chest tube could have been avoided because the spontaneous resolution of capnothorax was quickly identified using bedside lung ultrasonography.