Departments of Anesthesiology.
Neurosurgery.
J Neurosurg Anesthesiol. 2019 Jan;31(1):62-69. doi: 10.1097/ANA.0000000000000466.
Awake craniotomy paired with intraoperative magnetic resonance imaging (iMRI) is now the established technique for maximizing surgical resection, while preserving neurological function. However, leaving an unsecured airway patient in the iMRI gantry represents considerable risk. Our study aimed at identifying the incidence of critical adverse events in unsecured airway patients during iMRI as part of awake craniotomy.
We conducted a clinical chart review of consecutive awake craniotomies performed between November 1999 and December 2015. Sequences of iMRI performed without invasive airway management were selected for assessment and the incidence of critical adverse events, including general convulsive seizure, respiratory arrest, nausea/vomiting and agitation, was identified.
Critical adverse events occurred in 21 of 356 unsecured airway patients within 24 of the 579 iMRI sequences. In cases using the low-field strength open MRI scanner, emergency termination of scans due to patient decline was recorded in only 4 cases: no cases of cardiac arrest, accidental death, or thermal injury were recorded. Compared with cardiovascular monitoring, patient respiratory status was poorly recorded.
In terms of anesthesia, concurrent use of iMRI for awake craniotomy is clinically acceptable providing potential intraoperative complications can be controlled. Further, the configuration of the iMRI scanner as well as the reduced exposure from the lower magnetic field strength was found to impact patient safety management. Therefore when a conscious patient is left in the gantry without airway support, it is advisable that levels of oxygenation and ventilation should be monitored at all times.
清醒开颅术与术中磁共振成像(iMRI)相结合是最大限度地切除肿瘤、保留神经功能的既定技术。然而,让未固定气道的患者留在 iMRI 磁体间存在相当大的风险。我们的研究旨在确定在 iMRI 作为清醒开颅术一部分的无固定气道患者中发生严重不良事件的发生率。
我们对 1999 年 11 月至 2015 年 12 月连续进行的清醒开颅术进行了临床病历回顾。选择未进行有创气道管理的 iMRI 序列进行评估,并确定严重不良事件的发生率,包括全身惊厥发作、呼吸停止、恶心/呕吐和躁动。
在 579 次 iMRI 序列中的 24 小时内,536 例无固定气道患者中有 21 例发生严重不良事件。在使用低场强开放式 MRI 扫描仪的情况下,仅记录了 4 例由于患者病情恶化而紧急终止扫描的情况:未发生心脏骤停、意外死亡或热损伤的情况。与心血管监测相比,患者呼吸状况的记录较差。
就麻醉而言,在清醒开颅术中同时使用 iMRI 是临床可接受的,只要可以控制潜在的术中并发症。此外,iMRI 扫描仪的配置以及较低磁场强度降低的暴露度被发现会影响患者安全管理。因此,当意识清醒的患者在无气道支持的情况下留在磁体间时,建议始终监测氧合和通气水平。