We supplied oxygen via reverse delivery after the normal means of oxygen supply was discontinued because of packing damage at a reel-type outlet ; we also clarified the cause of the damage and performed a repair. An alarm on the anesthesia machine sounded at the time of a start-up inspection, and a decrease in the oxygen supply pressure was detected. We immediately asked for an alternative oxygen supply and changed the machine. Immediately after the change, the central oxygen supply pressure decreased, indicating a possible leakage. An airtight test showed a leakage on the 3rd floor of the hospital but not on the other floors including the 5th floor, on which the operating room and ward are located. Since no leakage was detected on the 5th floor, we decided to utilize a reverse delivery oxygen supply. To shut off the operating room from the central supply system, the shut-off bulb was closed. An oxygen cylinder was then connected to the wall outlet. In addition to these actions, other sections were examined and the cause of the problem was clarified. We discovered that the packing at the connection site of a reel-type outlet in the Department of Pediatric Dentistry for the Disabled on the 3rd floor had been damaged. The packing was replaced on the same day. The presently reported planned operation was successfully performed. However, depending on the size of the institution and the number of operations, patient safety should be prioritized by cancelling elective surgeries or selecting other oxygen supply methods. Preventive measures to avoid oxygen supply interruption, management at the time of oxygen supply failure, and the sharing of equipment-related knowledge are important.
