Kim Mi Young, Kim Eun Joo, Lee Ji Hyang, Lee Sang Kon, Ban Jong Suk, Min Byung Woo
Department of Anesthesiology and Pain Medicine, Daegu Fatima Hospital, Daegu, Korea.
Korean J Anesthesiol. 2009 Oct;57(4):493-498. doi: 10.4097/kjae.2009.57.4.493.
Unidirectional valve malfunction causes re-breathing of expired gas during anesthesia. Capnography is a useful method for monitoring the integrity of anesthetic equipment such as the unidirectional valves in a circular system. We report, here a case in which the capnography did not sound any rebreathing alarm, but the capnogram showed a prolonged plateau, an apparently short inspiratory period and a gradually sloping descending limb that stopped just short of baseline. As a result, capnography helped to identify an inspiratory unidirectional valve malfunction during the course of anesthesia. This study emphasizes the need to analyze the capnogram during every procedure involving anesthesia, in addition to preoperative checking of the Unidirectional valve.
单向阀故障会导致麻醉期间呼出气体的重复吸入。二氧化碳描记法是监测麻醉设备完整性的一种有用方法，例如循环系统中的单向阀。在此，我们报告一例，二氧化碳描记法未发出任何重复吸入警报，但二氧化碳图显示有延长的平台期、明显缩短的吸气期以及逐渐倾斜下降至基线前停止的下降支。结果，二氧化碳描记法有助于在麻醉过程中识别吸气单向阀故障。本研究强调，除术前检查单向阀外，在每例涉及麻醉的手术过程中都需要分析二氧化碳图。
