Department of Anesthesiology and Critical Care Medicine, Centre Hospitalier Universitaire Pitié-Salpêtrière, Paris, France.
Anesthesiology. 2012 Dec;117(6):1165-74. doi: 10.1097/ALN.0b013e318275561d.
Cardiac output (CO) is rarely monitored during surgery, and arterial pressure remains the only hemodynamic parameter for assessing the effects of volume expansion (VE). However, whether VE-induced changes in arterial pressure accurately reflect changes in CO has not been demonstrated. The authors studied the ability of VE-induced changes in arterial pressure and in pulse pressure variation to detect changes in CO induced by VE in the perioperative period.
The authors studied 402 patients in four centers. Hemodynamic variables were recorded before and after VE. Response to VE was defined as more than 15% increase in CO. The ability of VE-induced changes in arterial pressure to detect changes in CO was assessed using a gray zone approach.
VE increased CO of more than 15% in 205 patients (51%). Areas under the receiver operating characteristic curves for VE-induced changes in systolic, diastolic, means, and pulse pressure ranged between 0.64 and 0.70, and sensitivity and specificity ranged between 52 and 79%. For these four arterial pressure-derived parameters, large gray zones were found, and more than 60% of the patients lay within this inconclusive zone. A VE-induced decrease in pulse pressure variation of 3% or more allowed detecting a fluid-induced increase in CO of more than 15% with a sensitivity of 90% and a specificity of 77% and a gray zone between 2.2 and 4.7% decrease in pulse pressure variation including 14% of the patients.
Only changes in pulse pressure variation accurately detect VE-induced changes in CO and have a potential clinical applicability.
心脏输出量（CO）在手术中很少监测，动脉压仍然是评估容量扩张（VE）效果的唯一血流动力学参数。然而，VE 引起的动脉压变化是否准确反映 CO 的变化尚未得到证明。作者研究了 VE 引起的动脉压和脉搏压变化的能力，以检测围手术期 VE 引起的 CO 变化。
作者在四个中心研究了 402 名患者。在 VE 前后记录血流动力学变量。对 VE 的反应定义为 CO 增加超过 15%。使用灰色区域方法评估 VE 引起的动脉压变化检测 CO 变化的能力。
205 名患者（51%）的 VE 增加了超过 15%的 CO。VE 引起的收缩压、舒张压、平均压和脉搏压变化的受试者工作特征曲线下面积在 0.64 至 0.70 之间，敏感性和特异性在 52%至 79%之间。对于这四个动脉压衍生参数，发现存在较大的灰色区域，超过 60%的患者处于这个不确定的区域。VE 引起的脉搏压变化减少 3%或更多，可以检测到 15%以上的液体诱导的 CO 增加，其敏感性为 90%，特异性为 77%，灰色区域为 2.2%至 4.7%的脉搏压变化减少，包括 14%的患者。
只有脉搏压变化的变化才能准确检测 VE 引起的 CO 变化，具有潜在的临床应用价值。
