Hirota K, Hashimoto H, Kabara S, Tsubo T, Sato Y, Ishihara H, Matsuki A
Department of Anesthesiology, University of Hirosaki School of Medicine, Hirosaki, Japan.
Anesth Analg. 2001 Sep;93(3):776-80. doi: 10.1097/00000539-200109000-00044.
Near-fatal pulmonary embolism can occur immediately after tourniquet release after orthopedic surgeries. In this study, we determined the relationship between tourniquet time and the occurrence of pulmonary emboli in 30 patients undergoing arthroscopic knee surgeries, by using transesophageal echocardiography. The right atrium (RA) was continuously monitored by transesophageal echocardiography, and the number of emboli present was assessed with the following formula: Amount of emboli = 100 x [(total embolic area in the RA after tourniquet release) - (total area of emboli or artifact in the RA before tourniquet release)]/(RA area). The area was assessed 0-300 s after tourniquet release by using image-analysis software. The peak amount of emboli appeared approximately 50 s after tourniquet release. In addition, there was a significant correlation between amount of emboli (Ae [%]) and tourniquet time (Ttq [min]): (Ae = 0.1 x Ttq - 1.0, r = 0.795, P < 0.01). This study suggests that acute pulmonary embolism may occur within 1 min of tourniquet release and that the number of emboli is dependent on Ttq.
骨科手术后止血带松开后可能立即发生近乎致命的肺栓塞。在本研究中，我们通过经食管超声心动图确定了30例行关节镜膝关节手术患者的止血带时间与肺栓塞发生之间的关系。通过经食管超声心动图持续监测右心房（RA），并使用以下公式评估存在的栓子数量：栓子量 = 100×[（止血带松开后RA中的总栓塞面积）-（止血带松开前RA中的栓子或伪像总面积）]/（RA面积）。使用图像分析软件在止血带松开后0 - 300秒评估面积。栓子的峰值量出现在止血带松开后约50秒。此外，栓子量（Ae [%]）与止血带时间（Ttq [分钟]）之间存在显著相关性：（Ae = 0.1×Ttq - 1.0，r = 0.795，P < 0.01）。本研究表明，急性肺栓塞可能在止血带松开后1分钟内发生，并且栓子数量取决于止血带时间。
