Huette Pierre, Ellouze Omar, Abou-Arab Osama, Guinot Pierre-Grégoire
Anaesthesiology and Critical Care Department, Cardiothoracic ICU, Amiens University Hospital, Amiens, France.
Anaesthesiology and Critical Care Department, Cardiovascular ICU, Dijon University Hospital, Dijon, France.
J Thorac Dis. 2019 Jul;11(Suppl 11):S1551-S1557. doi: 10.21037/jtd.2019.01.109.
Alteration of tissue perfusion is a main contributor to organ dysfunction in high-risk surgical patients. The difference between venous carbon dioxide and arterial carbon dioxide pressure (pCO gap) has been described as a parameter reflecting tissue hypoperfusion in critically ill patients who are insufficiently resuscitated. The pCO gap/CavO ratio has also been described as an indicator of the respiratory quotient, thus the relationship between DO and VO. Most of the knowledge about the pCO gap and the pCO gap/CavO ratio has come from studies in the literature on animal models or intensive care unit (ICU) patients. To date, publications pertaining to the operative setting are sparse. In the present review, we will first discuss the physiological background of the pCO gap and CO-O derived parameters used in the operating room. Few studies have focused on the clinical relevance of the pCO gap in high-risk non-cardiac surgical patients. Prospective observational studies with a small sample size and retrospective studies have shown that the pCO gap may be a useful complementary tool to identify patients who remain insufficiently optimized hemodynamically. In a few studies, a high pCO gap was associated with postoperative complications following non-cardiac high-risk surgery. Results of observational studies conducted in patients undergoing cardiac surgery are contradictory. We focused on the divergence between non-cardiac surgery, cardiac surgery, and septic critically ill patients. When analyzing the literature, we can find some explanations for the discrepancies in the published results between cardiac and non-cardiac surgery. Finally, we will discuss the clinical utility of the pCO gap in high-risk surgical patients.
组织灌注改变是高危手术患者器官功能障碍的主要原因。静脉血二氧化碳分压与动脉血二氧化碳分压之差（pCO₂差值）已被描述为反映复苏不足的危重症患者组织灌注不足的一个参数。pCO₂差值与中心静脉血氧饱和度（CvO₂）的比值也被描述为呼吸商的一个指标，从而反映氧输送（DO）与氧消耗（VO）之间的关系。关于pCO₂差值和pCO₂差值/CvO₂比值的大多数知识来自动物模型或重症监护病房（ICU）患者的文献研究。迄今为止，有关手术环境的相关出版物较少。在本综述中，我们将首先讨论手术室中使用的pCO₂差值和基于心输出量（CO）-氧输送（O₂）的参数的生理背景。很少有研究关注pCO₂差值在高危非心脏手术患者中的临床相关性。小样本量的前瞻性观察研究和回顾性研究表明，pCO₂差值可能是识别血流动力学仍未充分优化患者的有用补充工具立。在一些研究中，高pCO₂差值与非心脏高危手术后的术后并发症相关。在心脏手术患者中进行的观察性研究结果相互矛盾。我们关注非心脏手术、心脏手术和脓毒症危重症患者之间的差异。在分析文献时，我们可以找到一些关于心脏手术和非心脏手术已发表结果差异的解释。最后，我们将讨论pCO₂差值在高危手术患者中的临床应用。
