Emergency Department, University Hospital of Bordeaux, Bordeaux, France; Cardiovascular Adaptation to Ischemia, National Institute of Health and Medical Research, INSERM U1034, Pessac, France; Cardiovascular Adaptation to Ischemia, University of Bordeaux, Pessac, France.
J Cardiothorac Vasc Anesth. 2013 Dec;27(6):1101-7. doi: 10.1053/j.jvca.2013.03.030. Epub 2013 Sep 21.
Infrarenal aortic cross-clamping (ACC) induces hemodynamic disturbances that may affect respiratory-induced variations in stroke volume and, therefore, affect the ability of dynamic parameters such as pulse-pressure variation (PPV) to predict fluid responsiveness. Since this issue has not been investigated yet to authors' knowledge, the hypothesis was tested that ACC may change PPV and impair its ability to predict fluid responsiveness.
Prospective laboratory experiment.
A university research laboratory.
Nineteen anesthetized and mechanically ventilated pigs.
Two courses of volume expansion were performed using 500 mL of saline before and during ACC. Animals were monitored using a systemic arterial catheter, and a pulmonary arterial catheter (stroke volume, central venous pressure, pulmonary arterial occlusion pressure). Animals were defined as responders to volume expansion if stroke volume increased ≥ 15%.
Before ACC, 13 animals were responders. Fluid responsiveness was predicted by a PPV ≥ 14% with a sensitivity of 77% (95% CI = 46%-95%) and a specificity of 83% (95% CI = 36%-97%). The area under the receiver operating characteristic curve was 0.90(95% CI = 0.67-0.99) and was higher than those generated for central venous pressure and pulmonary arterial occlusion pressure. ACC induced an increase in PPV (p<0.0005). During ACC, 8 animals were responders. An 18% PPV threshold discriminated between responders and non-responders to volume expansion, with a sensitivity of 87% (95% CI = 47%-98%) and a specificity of 54% (95% CI = 23%-83%). The area under the receiver operating characteristic curve was 0.72 (95% CI = 0.47-0.90) and was not different from those generated for central venous pressure and pulmonary arterial occlusion pressure.
ACC induced a significant increase in PPV and reduced its ability to predict fluid responsiveness.
腹主动脉阻断（ACC）会引起血流动力学紊乱，这可能会影响呼吸引起的每搏量变化，并因此影响诸如脉压变化（PPV）等动态参数预测液体反应性的能力。由于作者所知，这一问题尚未得到研究，因此假设 ACC 可能会改变 PPV 并削弱其预测液体反应性的能力。
前瞻性实验室实验。
大学研究实验室。
19 头麻醉和机械通气的猪。
在 ACC 前后使用 500 毫升生理盐水进行了两次容量扩张。通过全身动脉导管和肺动脉导管（每搏量、中心静脉压、肺动脉闭塞压）监测动物。如果每搏量增加≥15%，则将动物定义为对容量扩张有反应。
在 ACC 之前，有 13 只动物有反应。PPV≥14%预测液体反应性的灵敏度为 77%（95%置信区间=46%-95%），特异性为 83%（95%置信区间=36%-97%）。接受者操作特征曲线下的面积为 0.90（95%置信区间=0.67-0.99），高于中心静脉压和肺动脉闭塞压生成的面积。ACC 引起 PPV 增加（p<0.0005）。在 ACC 期间，有 8 只动物有反应。18%的 PPV 阈值可区分对容量扩张有反应和无反应的动物，灵敏度为 87%（95%置信区间=47%-98%），特异性为 54%（95%置信区间=23%-83%）。接受者操作特征曲线下的面积为 0.72（95%置信区间=0.47-0.90），与中心静脉压和肺动脉闭塞压生成的面积无差异。
ACC 引起 PPV 显著增加，并降低其预测液体反应性的能力。
