Hemodynamic response to fluid removal during hemodialysis: categorization of causes of intradialytic hypotension
Hemodynamic response to fluid removal during hemodialysis: categorization of causes of intradialytic hypotension
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DOI：
10.1093/ndt/gfy048
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发表时间：
2018-09-01
影响因子：
6.1
通讯作者：
Williams, Caroline
中科院分区：
文献类型：
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作者：
Levin, Nathan W.;de Abreu, Marcia H. F. G.;Williams, Caroline
背景透析中低血压是一个临床上重要的问题，然而，血液动力学的基础超滤和随之而来的水肿事件还没有得到全面的研究。在美国和巴西的54例透析患者的263次血液透析中，使用新型局部阻抗心电图设备（NICaS，NI Medical，Peta Tikva，Israel）评估了透析中心输出量、心功率和外周阻力与治疗前测量值的变化，目的是确定血压降低时的各种血流动力学趋势。在736次透析中和透析后评价中，99次（13.5%）发生低血压发作。对发作的血流动力学特征进行了分类：（i）35%的发作的心脏动力指数显著降低36%，从0.66 [95%置信区间（CI）0.60-0.72]降至0.43（95% CI 0.37 -0.48）[w/m2]，总外周阻力指数略有降低。(ii)总外周阻力指数在37.4%的发作中显著降低了33%，从3342（95% CI 2824-3859）降至2251（95% CI 1900-2602）[dyn x s/cm（5）x m（2）]，心脏动力指数略有降低。(iii)在27.3%的发作中，心脏功率指数和总外周阻力指数均显著降低，心脏动力指数从0.63（95% CI 0.57-0.70）至0.48（95%CI 0.42-0.53）[w/m2]，总外周阻力指数从2964（95%CI 2428-3501）增加23%至2266（95%CI 1891-2642）。血液动力学特征明确定义了心脏功率降低和/或血管舒张的特定血液动力学机制作为基础透析中水肿发作。心功率降低（血压和心输出量降低）可能是由于高超滤率导致的前负荷降低，再充盈不足或目标体重较低。外周阻力降低（血压降低和心输出量增加）可能是相对血管舒张的结果，因为动脉不会收缩以补偿自主功能障碍引起的体积减少。由于这两种现象是独立的，它们可能同时出现。基于这些结果，降低超滤率和增加目标体重以改善前负荷或立即采取治疗措施以增加外周阻力是维持透析患者血压和预防弥漫性缺血并发症的合理措施。
Background. Intradialytic hypotension is a clinically significant problem, however, the hemodynamics that underlie ultrafiltration and consequent hypotensive episodes has not been studied comprehensively.Methods. Intradialytic cardiac output, cardiac power and peripheral resistance changes from pretreatment measurements were evaluated using a novel regional impedance cardiographic device (NICaS, NI Medical, Peta Tikva, Israel) in 263 hemodialysis sessions in 54 patients in dialysis units in the USA and Brazil with the goal of determining the various hemodynamic trends as blood pressure decreases.Results. Hypotensive episodes occurred in 99 (13.5%) of 736 intra- and postdialytic evaluations. The hemodynamic profiles of the episodes were categorized: (i) The cardiac power index significantly decreased in 35% of episodes by 36%, from 0.66 [95% confidence interval (CI) 0.60-0.72] to 0.43 (95% CI 037-0.48) [w/m(2)] with a small reduction in the total peripheral resistance index. (ii) The total peripheral resistance index significantly decreased in 37.4% of episodes by 33%, from 3342 (95% CI 2824-3859) to 2251 (95% CI 1900-2602) [dyn x s/cm(5) x m(2)] with a small reduction in the cardiac power index. (iii) Both the cardiac power index and total peripheral resistance index significantly decreased in 27.3% of episodes, the cardiac power index by 25% from 0.63 (95% CI 0.57-0.70) to 0.48 (95% CI 0.42-0.53) [w/m(2)] and the total peripheral resistance index by 23% from 2964 (95% CI 2428-3501) to 2266 (95% CI 1891-2642).Conclusions. The hemodynamic profiles clearly define specific hemodynamic mechanisms of cardiac power reduction and/or vasodilatation as underlying intradialytic hypotensive episodes. A reduction in cardiac power (reduction of both blood pressure and cardiac output) could be the result of preload reduction due to a high ultrafiltration rate with not enough refilling or low target weight. A reduction in peripheral resistance (reduction in blood pressure and increase in cardiac output) could be the result of relative vasodilatation as arteries do not contract to compensate for volume reduction due to autonomous dysfunction. As both phenomena are independent, they may appear at the same time. Based on these results, a reduction of ultrafiltration rate and an increase in target weight to improve preload or immediate therapeutic actions to increase peripheral resistance are rational measures that could be taken to maintain blood pressure and prevent hypotensive ischemic complications in dialysis patients.