Keidan Ilan, Arzillo Samantha, Vasilopoulos Terrie, Ben-Menachem Erez, Gravenstein Nikolaus, McGough Edward
Anesthesiology, University of Florida College of Medicine, Gainesville, USA.
Anesthesiology/Orthopedics and Rehabilitation, University of Florida College of Medicine, Gainesville, USA.
Cureus. 2021 Oct 9;13(10):e18621. doi: 10.7759/cureus.18621. eCollection 2021 Oct.
Introduction Cardiac output/pulmonary blood flow measurement is an important way to assess patients during the perioperative period, as well as patients who are critically ill. Current methods of assessing cardiac output have limitations. One indicator of cardiac output may be the expired carbon dioxide (CO) partial pressure response to intravenous sodium bicarbonate (IVSB), which is rapidly converted to CO. Methods We conducted an initial evaluation of the relationship between expired CO partial pressure and blood flow after a bolus of IVSB. To assess this relationship, we used a cardiopulmonary bypass circuit with predetermined blood flows in a laboratory trial and then assessed 18 patients undergoing surgery requiring cardiopulmonary bypass. Results For the laboratory portion of this pilot study, higher peak expired CO, faster time to reach peak, higher area under the curve, and greater kurtosis of peak were observed at higher cardiac output flow rates, and higher mean expired CO was significantly associated with higher flow rates (p < 0.001). In the human study, higher mean (p = 0.023) and peak expired CO (p = 0.028) were both significantly associated with higher cardiac output flow rates. Conclusions This technique may be a way to intermittently assess cardiac output or improve accuracy when used in conjunction with other continuous output monitors.
引言 心输出量/肺血流量测量是围手术期评估患者以及危重症患者的重要方法。目前评估心输出量的方法存在局限性。心输出量的一个指标可能是呼出二氧化碳（CO）分压对静脉注射碳酸氢钠（IVSB）的反应，IVSB会迅速转化为CO。方法 我们对静脉注射一次大剂量IVSB后呼出CO分压与血流量之间的关系进行了初步评估。为评估这种关系，我们在实验室试验中使用了具有预定血流量的体外循环回路，然后对18例接受需要体外循环的手术患者进行了评估。结果 在这项初步研究的实验室部分，在心输出量流速较高时，观察到呼出CO峰值更高、达到峰值的时间更快、曲线下面积更大以及峰值的峰度更大，并且呼出CO平均水平较高与流速较高显著相关（p < 0.001）。在人体研究中，呼出CO平均水平较高（p = 0.023）和峰值较高（p = 0.028）均与心输出量流速较高显著相关。结论 这项技术可能是一种间歇性评估心输出量的方法，或者与其他连续输出监测器联合使用时可提高准确性。
