Cui Fan, Zhao Wei, Mu Dong-Liang, Zhao Xu, Li Xue-Ying, Wang Dong-Xin, Jia Hui-Qun, Dai Feng, Meng Lingzhong
From the Department of Anesthesiology and Critical Care, Peking University First Hospital, Beijing, China.
Department of Anesthesiology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, China.
Anesth Analg. 2021 Jul 1;133(1):176-186. doi: 10.1213/ANE.0000000000005489.
The association between cerebral desaturation and postoperative delirium in thoracotomy with one-lung ventilation (OLV) has not been specifically studied.
A prospective observational study performed in thoracic surgical patients. Cerebral tissue oxygen saturation (Scto2) was monitored on the left and right foreheads using a near-infrared spectroscopy oximeter. Baseline Scto2 was measured with patients awake and breathing room air. The minimum Scto2 was the lowest measurement at any time during surgery. Cerebral desaturation and hypersaturation were an episode of Scto2 below and above a given threshold for ≥15 seconds during surgery, respectively. The thresholds based on relative changes by referring to the baseline measurement were <80%, <85%, <90%, <95%, and <100% baseline for desaturation and >105%, >110%, >115%, and >120% baseline for hypersaturation. The thresholds based on absolute values were <50%, <55%, <60%, <65%, and <70% for desaturation and >75%, >80%, >85%, and >90% for hypersaturation. The given area under the threshold (AUT)/area above the threshold (AAT) was analyzed. Delirium was assessed until postoperative day 5. The primary analysis was the association between the minimum Scto2 and delirium using multivariable logistic regression controlled for confounders (age, OLV time, use of midazolam, occurrence of hypotension, and severity of pain). The secondary analysis was the association between cerebral desaturation/hypersaturation and delirium, and between the AUT/AAT and delirium using multivariable logistic regression controlled for the same confounders. Multiple testing was corrected using the Holm-Bonferroni method. We additionally monitored somatic tissue oxygen saturation on the forearm and upper thigh.
Delirium occurred in 35 (20%) of 175 patients (65 ± 6 years old). The minimum left or right Scto2 was not associated with delirium. Cerebral desaturation defined by <90% baseline for left Scto2 (odds ratio [OR], 5.82; 95% confidence interval [CI], 2.12-19.2; corrected P =.008) and <85% baseline for right Scto2 (OR, 4.27; 95% CI, 1.77-11.0; corrected P =.01) was associated with an increased risk of delirium. Cerebral desaturation defined by other thresholds, cerebral hypersaturation, the AUT/AAT, and somatic desaturation and hypersaturation were all not associated with delirium.
Cerebral desaturation defined by <90% baseline for left Scto2 and <85% baseline for right Scto2, but not the minimum Scto2, may be associated with an increased risk of postthoracotomy delirium. The validity of these thresholds needs to be tested by randomized controlled trials.
尚未专门研究开胸单肺通气（OLV）期间脑氧饱和度降低与术后谵妄之间的关联。
对胸外科患者进行一项前瞻性观察性研究。使用近红外光谱血氧仪监测左右前额的脑组织氧饱和度（Scto2）。在患者清醒并呼吸室内空气时测量基线Scto2。最低Scto2是手术期间任何时间的最低测量值。脑氧饱和度降低和过高饱和度分别是手术期间Scto2低于和高于给定阈值≥15秒的情况。基于相对于基线测量的相对变化的阈值，氧饱和度降低的阈值为<80%、<85%、<90%、<95%和<100%基线，过高饱和度的阈值为>105%、>110%、>115%和>120%基线。基于绝对值的阈值，氧饱和度降低为<50%、<55%、<60%、<65%和<70%，过高饱和度为>75%、>80%、>85%和>90%。分析阈值以下面积（AUT）/阈值以上面积（AAT）。评估术后第5天之前的谵妄情况。主要分析是使用多变量逻辑回归控制混杂因素（年龄、OLV时间、咪达唑仑的使用、低血压的发生和疼痛严重程度）来分析最低Scto2与谵妄之间的关联。次要分析是使用多变量逻辑回归控制相同混杂因素来分析脑氧饱和度降低/过高饱和度与谵妄之间的关联，以及AUT/AAT与谵妄之间的关联。使用Holm-Bonferroni方法校正多重检验。我们还监测了前臂和大腿上部的躯体组织氧饱和度。
175例患者（65±6岁）中有35例（20%）发生谵妄。左右最低Scto2与谵妄无关。左Scto2基线<90%定义的脑氧饱和度降低（比值比[OR]，5.82；95%置信区间[CI]，2.12 - 19.2；校正P =.008）和右Scto2基线<85%定义的脑氧饱和度降低（OR，4.27；95%CI，1.77 - 11.0；校正P =.01）与谵妄风险增加相关。由其他阈值定义的脑氧饱和度降低、脑过高饱和度、AUT/AAT以及躯体氧饱和度降低和过高饱和度均与谵妄无关。
左Scto2基线<90%和右Scto2基线<85%定义的脑氧饱和度降低而非最低Scto2，可能与开胸术后谵妄风险增加相关。这些阈值的有效性需要通过随机对照试验进行检验。
