Slbin M S, Babinski M, Maroon J C, Jannetta P J
Acta Anaesthesiol Scand. 1976;20(2):117-28. doi: 10.1111/j.1399-6576.1976.tb05018.x.
From the surgical aspect, the sitting position gives good surgical access to the operative site, improves venous drainage, gives a better view of facial area for monitoring evoked responses from cranial nerve stimulation and allows for better ventilation. Conversely, the sitting position can present complications such as air emboli, postural hypotension and serious cardiac arrhythmias due to surgical stimulation of cranial nerves and brainstem. This paper presents our clinical experience in 180 neurosurgical procedures on the posterior fossa in the sitting position. The standardized anesthetic technique consisted of narcotic, muscle relaxant, nitrous oxide and controlled ventilation. All patients were monitored with ECG, direct arterial and venous pressure, discontinuous blood gases, and expiratory CO2 and urinary output. Air embolism was detected via Doppler ultrasonic detector and evacuated through a right atrial catheter. Air was detected, visualized and aspirated in 45 cases for an incidence of 25%, with most episodes occurring early in the procedure. In 11 cases (6%) air was detected on closure. There were no deaths in this series. Fifty-eight patients (32%) had a 10-20 mmHg drop in blood pressure on reaching the sitting position, 19 became temporarily hypertensive (10.5%), and the remainder were normotensive. In 46 patients (25%), bradycardia developed during retraction-manipulation-stimulation of structures on or adjacent to brainstem as well as to cranial nerves. Surgical stress also accounted for the 13 patients (7%) having frequent premature ventricular extrasystoles. One case of profound hypotension and another case of virtual cardiac standstill were noted during the use of the bipolar electrocautery at or near the fifth nerve exit from brainstem. Additional hemodynamic data, the physiopathology, diagnosis and treatment of air embolism is discussed.
从手术角度来看，坐位能为手术部位提供良好的手术入路，改善静脉引流，能更好地观察面部区域以监测来自颅神经刺激的诱发反应，并有利于更好的通气。相反，坐位可能会出现一些并发症，如空气栓塞、体位性低血压以及由于手术刺激颅神经和脑干导致的严重心律失常。本文介绍了我们在180例坐位后颅窝神经外科手术中的临床经验。标准化的麻醉技术包括使用麻醉剂、肌肉松弛剂、氧化亚氮并进行控制通气。所有患者均通过心电图、直接动脉和静脉压、间断血气分析、呼气末二氧化碳监测以及尿量监测。通过多普勒超声探测器检测空气栓塞，并通过右心房导管进行排气。在45例患者中检测到空气并可视化及抽出，发生率为25%，大多数情况发生在手术早期。在11例（6%）患者中，关闭切口时检测到空气。本系列中无死亡病例。58例患者（32%）在达到坐位时血压下降10 - 20 mmHg，19例患者（10.5%）出现短暂高血压，其余患者血压正常。在46例患者（25%）中，在牵拉 - 操作 - 刺激脑干或其附近以及颅神经结构时出现心动过缓。手术应激还导致13例患者（7%）频繁出现室性早搏。在使用双极电凝器于脑干第五神经出口处或其附近时，记录到1例严重低血压和另1例几乎心脏停搏的病例。文中还讨论了额外的血流动力学数据、空气栓塞的生理病理学、诊断和治疗。
