Ann Junggun, Jung Sung Mee, Park Sang-Jin
Department of Anesthesiology and Pain Medicine, Yeungnam University School of Medicine, Daegu, Korea.
Korean J Anesthesiol. 2017 Apr;70(2):213-216. doi: 10.4097/kjae.2017.70.2.213. Epub 2016 Oct 25.
Severe hypercapnia can be predicted by a decrease in cerebral electrical activity. The authors describe a sudden decrease in spectral entropy due to severe hypercapnia-induced respiratory acidosis in a patient with chronic pulmonary obstructive disease during lung resection. After two and a half hours of low tidal volume ventilation in the lateral position, the state entropy suddenly dropped from 45 to 7, without any changes in the effect-site concentration of propofol, end-tidal carbon dioxide (CO) tension, oxygen saturation, or arterial pressure. However, arterial blood gas analysis showed severe respiratory acidosis (pH 7.01, PaCO 115 mmHg and PaO 246 mmHg with FIO of 0.5). Immediate hyperventilation improved the state entropy and acid-base balance. Electroencephalography-based spectral entropy can detect severe hypercapnia in chronic pulmonary obstructive disease patients with a large arterial to end-tidal CO difference due to prolonged hypoventilation during thoracic surgery.
严重高碳酸血症可通过脑电活动的降低来预测。作者描述了一名慢性阻塞性肺疾病患者在肺切除术中因严重高碳酸血症诱发呼吸性酸中毒导致频谱熵突然下降的情况。在侧卧位进行两个半小时的低潮气量通气后，状态熵突然从45降至7，而丙泊酚效应室浓度、呼气末二氧化碳（CO）分压、血氧饱和度或动脉压均无变化。然而，动脉血气分析显示严重呼吸性酸中毒（pH 7.01，PaCO₂ 115 mmHg，PaO₂ 46 mmHg，吸入氧分数为0.5）。立即进行过度通气可改善状态熵和酸碱平衡。基于脑电图的频谱熵可在胸外科手术期间因长时间通气不足导致动脉血与呼气末CO₂差值较大的慢性阻塞性肺疾病患者中检测到严重高碳酸血症。
