Jung Seungho, Kim Jeongmin, Na Sungwon, Nam Won Seok, Kim Do-Hyeong
Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul 03722, Korea.
J Clin Med. 2021 Jun 17;10(12):2676. doi: 10.3390/jcm10122676.
Predicting fluid responsiveness in patients under mechanical ventilation with low tidal volume (VT) is challenging. This study evaluated the ability of carotid corrected flow time (FTc) assessed by ultrasound for predicting the fluid responsiveness during low VT ventilation. Patients under postoperative mechanical ventilation and clinically diagnosed with hypovolemia were enrolled. Carotid FTc and pulse pressure variation (PPV) were measured at VT of 6 and 10 mL/kg predicted body weight (PBW). FTc was calculated using both Bazett's (FTcB) and Wodey's (FTcW) formulas. Fluid responsiveness was defined as a ≥15% increase in the stroke volume index assessed by FloTrac/Vigileo monitor after administration of 8 mL/kg of balanced crystalloid. Among 36 patients, 16 (44.4%) were fluid responders. The areas under the receiver operating characteristic curves (AUROCs) for the FTcB at VT of 6 and 10 mL/kg PBW were 0.897 (95% confidence interval [95% CI]: 0.750-0.973) and 0.895 (95% CI: 0.748-0.972), respectively. The AUROCs for the FTcW at VT of 6 and 10 mL/kg PBW were 0.875 (95% CI: 0.722-0.961) and 0.891 (95% CI: 0.744-0.970), respectively. However, PPV at VT of 6 mL/kg PBW (AUROC: 0.714, 95% CI: 0.539-0.852) showed significantly lower accuracy than that of PPV at VT of 10 mL/kg PBW (AUROC: 0.867, 95% CI: 0.712-0.957; = 0.034). Carotid FTc can predict fluid responsiveness better than PPV during low VT ventilation. However, further studies using automated continuous monitoring system are needed before its clinical use.
预测低潮气量（VT）机械通气患者的液体反应性具有挑战性。本研究评估了通过超声评估的颈动脉校正血流时间（FTc）预测低潮气量通气期间液体反应性的能力。纳入术后机械通气且临床诊断为低血容量的患者。在预测体重（PBW）6和10 mL/kg的VT时测量颈动脉FTc和脉压变异（PPV）。使用巴泽特公式（FTcB）和沃迪公式（FTcW）计算FTc。液体反应性定义为给予8 mL/kg平衡晶体液后，经FloTrac/Vigileo监测仪评估的每搏量指数增加≥15%。36例患者中，16例（44.4%）为液体反应者。在PBW 6和10 mL/kg的VT时，FTcB的受试者工作特征曲线下面积（AUROC）分别为0.897（95%置信区间[95%CI]：0.750-0.973）和0.895（95%CI：0.748-0.972）。在PBW 6和10 mL/kg的VT时，FTcW的AUROC分别为0.875（95%CI：0.722-0.961）和0.891（95%CI：0.744-0.970）。然而，PBW 6 mL/kg的VT时PPV（AUROC：0.714，95%CI：0.539-0.852）的准确性显著低于PBW 10 mL/kg的VT时PPV（AUROC：0.867，95%CI：0.712-0.957；P = 0.034）。在低潮气量通气期间，颈动脉FTc比PPV能更好地预测液体反应性。然而，在临床应用前，需要使用自动连续监测系统进行进一步研究。
