儿童全身麻醉下心功能如何评估？动态电容法测量还是经食道心脏超声检查？

儿童全身麻醉下心功能如何评估？动态电容法测量还是经食道心脏超声检查？

摘要译文

麻醉儿童的心输出量评估：动态电容法测量与经食道多普勒超声检查

背景：

本研究的目的是比较经食道多普勒心输出量测量（esophageal Doppler cardiac output，COEDM）与参考方法有效肺血流法心输出量测量（effective pulmonary blood flow cardiac output，COEPBF），以确定绝对值的一致性以及检测小儿外科患者心输出量（cardiac output，CO）变化的能力。此外，还评估了这两种方法与无创血压（noninvasive blood pressure，NIBP）参数之间的关系。

方法：

这项前瞻性观察队列研究中共纳入15名择期手术的美国麻醉学学会（American Society of Anesthesiology，ASA）分级I和II级儿童，中位年龄8个月，中位体重9 kg。在呼气末正压（positive end-expiratory pressure，PEEP）3cm H2O下进行基线COEPBF/COEDM/NIBP测量。PEEP增加至10 cm H2O，并在1分钟和3分钟后记录COEPBF/COEDM/NIBP。然后将PEEP降至3 cm H2O，并在3分钟后重复所有测量。最后，为了增加CO，静脉注射20-µg kg-1阿托品，并在5分钟后再次记录所有测量值。检查COEDM和COEPBF配对记录的一致性和趋势能力，并分析所有参数对血流动力学挑战的反应。

结果：

COEDM和COEPBF（COEDM-COEPBF）之间的偏差为-17 mL •kg-1 •min-1（一致性限为-67至+33 mL •kg-1 •min-1），平均百分比误差为32%（95%可信区间[CI]，25-37），一致性率为71%（95%可信区间，63-80）。

PEEP操作引起的血流动力学变化导致COEPBF绝对数显著减少（155 mL •kg-1 •min-1[95%可信区间，151-159]至127 mL •kg-1 •min-1[95%可信区间，113-141]），并且在应用PEEP 10后3分钟相应相对减少18%（95%可信区间，14-22）。COEDM未检测到相应的减少。

在应用PEEP 10后1分钟和3分钟，平均动脉压分别下降5%（95%CI，2-8）和6%（95%CI，2-10）。在应用PEEP 10后3分钟，收缩压相对降低5%（95%CI，2-10）。

除心率在阿托品后5分钟相对增加4%（95%CI，1-7，P=0.02）外，所有记录的参数对阿托品给药均无反应。

结论：

COEDM无法检测到PEEP增加引起的CO减少，而COEPBF和NIBP在最小程度上检测到CO的这些变化。在NIBP出现明显变化之前，COEPBF对CO轻微减少就能产生反应，提示COEPBF可能是机械通气儿童血流动力学监测的潜在有用工具。

原文摘要

Cardiac Output Assessments in Anesthetized Children: Dynamic Capnography Versus Esophageal Doppler

Background: The objective of this study was to compare esophageal Doppler cardiac output (COEDM) against the reference method effective pulmonary blood flow cardiac output (COEPBF), for agreement of absolute values and ability to detect change in cardiac output (CO) in pediatric surgical patients. Furthermore, the relationship between these 2 methods and noninvasive blood pressure (NIBP) parameters was evaluated.

Methods: Fifteen children American Society of Anesthesiology (ASA) I and II (median age, 8 months; median weight, 9 kg) scheduled for surgery were investigated in this prospective observational cohort study. Baseline COEPBF/COEDM/NIBP measurements were made at positive end-expiratory pressure (PEEP) 3 cm H2O. PEEP was increased to 10 cm H2O and COEPBF/COEDM/NIBP was recorded after 1 and 3 minutes. PEEP was then lowered to 3 cm H2O, and all measurements were repeated after 3 minutes. Finally, 20-µg kg-1 intravenous atropine was given with the intent to increase CO, and all measurements were recorded again after 5 minutes. Paired recordings of COEDM and COEPBF were examined for agreement and trending ability, and all parameters were analyzed for their responses to the hemodynamic challenges.

Results: Bias between COEDM and COEPBF (COEDM - COEPBF) was -17 mL kg-1 min-1 (limits of agreement, -67 to +33 mL kg-1 min-1) with a mean percentage error of 32% (95% confidence interval [CI], 25-37) and a concordance rate of 71% (95% CI, 63-80). The hemodynamic interventions caused by PEEP manipulations resulted in significant decrease in COEPBF absolute numbers (155 mL kg-1 min-1 [95% CI, 151-159] to 127 mL kg-1 min-1 [95% CI, 113-141]) and a corresponding relative decrease of 18% (95% CI, 14-22) 3 minutes after application of PEEP 10. No corresponding decreases were detected by COEDM. Mean arterial pressure showed a relative decrease with 5 (95% CI, 2-8) and 6% (95% CI, 2-10) 1 and 3 minutes after the application of PEEP 10, respectively. Systolic arterial pressure showed a relative decrease of 5% (95% CI, 2-10) 3 minutes after application of PEEP 10. None of the recorded parameters responded to atropine administration except for heart rate that showed a 4% relative increase (95% CI, 1-7, P = .02) 5 minutes after atropine.

Conclusions: COEDM was unable to detect the reduction of CO cause by increased PEEP, whereas COEPBF and to a minimal extent NIBP detected these changes in CO. The ability of COEPBF to react to minor reductions in CO, before noticeable changes in NIBP are seen, suggests that COEPBF may be a potentially useful tool for hemodynamic monitoring in mechanically ventilated children.

打赏