Wexler Orren, Morgan Mary A M, Gough Michael S, Steinmetz Sherry D, Mack Cynthia M, Darling Denise C, Doolin Kathleen P, Apostolakos Michael J, Graves Brian T, Frampton Mark W, Chen Xucai, Pietropaoli Anthony P
Division of Pulmonary and Critical Care Medicine, Department of Medicine, University of Rochester Medical Center, 601 Elmwood Avenue, Rochester, NY 14642, USA.
Crit Care. 2012 Dec 12;16(2):R38. doi: 10.1186/cc11223.
Ultrasound measurements of brachial artery reactivity in response to stagnant ischemia provide estimates of microvascular function and conduit artery endothelial function. We hypothesized that brachial artery reactivity would independently predict severe sepsis and severe sepsis mortality.
This was a combined case-control and prospective cohort study. We measured brachial artery reactivity in 95 severe sepsis patients admitted to the medical and surgical intensive care units of an academic medical center and in 52 control subjects without acute illness. Measurements were compared in severe sepsis patients versus control subjects and in severe sepsis survivors versus nonsurvivors. Multivariable analyses were also conducted.
Hyperemic velocity (centimeters per cardiac cycle) and flow-mediated dilation (percentage) were significantly lower in severe sepsis patients versus control subjects (hyperemic velocity: severe sepsis = 34 (25 to 48) versus controls = 63 (52 to 81), P < 0.001; flow-mediated dilation: severe sepsis = 2.65 (0.81 to 4.79) versus controls = 4.11 (3.06 to 6.78), P < 0.001; values expressed as median (interquartile range)). Hyperemic velocity, but not flow-mediated dilation, was significantly lower in hospital nonsurvivors versus survivors (hyperemic velocity: nonsurvivors = 25 (16 to 28) versus survivors = 39 (30 to 50), P < 0.001; flow-mediated dilation: nonsurvivors = 1.90 (0.68 to 3.41) versus survivors = 2.96 (0.91 to 4.86), P = 0.12). Lower hyperemic velocity was independently associated with hospital mortality in multivariable analysis (odds ratio = 1.11 (95% confidence interval = 1.04 to 1.19) per 1 cm/cardiac cycle decrease in hyperemic velocity; P = 0.003).
Brachial artery hyperemic blood velocity is a noninvasive index of microvascular function that independently predicts mortality in severe sepsis. In contrast, brachial artery flow-mediated dilation, reflecting conduit artery endothelial function, was not associated with mortality in our severe sepsis cohort. Brachial artery hyperemic velocity may be a useful measurement to identify patients who could benefit from novel therapies designed to reverse microvascular dysfunction in severe sepsis and to assess the physiologic efficacy of these treatments.
超声测量肱动脉对静态缺血的反应性可提供微血管功能和传导动脉内皮功能的评估。我们假设肱动脉反应性可独立预测严重脓毒症及严重脓毒症死亡率。
这是一项病例对照与前瞻性队列相结合的研究。我们测量了95例入住一所学术医疗中心内科和外科重症监护病房的严重脓毒症患者以及52例无急性疾病的对照受试者的肱动脉反应性。对严重脓毒症患者与对照受试者、严重脓毒症幸存者与非幸存者的测量结果进行了比较。还进行了多变量分析。
严重脓毒症患者的充血速度（每心动周期厘米数）和血流介导的舒张（百分比）显著低于对照受试者（充血速度：严重脓毒症患者=34（25至48），对照受试者=63（52至81），P<0.001；血流介导的舒张：严重脓毒症患者=2.65（0.81至4.79），对照受试者=4.11（3.06至6.78），P<0.001；数值表示为中位数（四分位间距））。住院非幸存者的充血速度显著低于幸存者，但血流介导的舒张无显著差异（充血速度：非幸存者=25（16至28），幸存者=39（30至50），P<0.001；血流介导的舒张：非幸存者=1.90（0.68至3.41），幸存者=2.96（0.91至4.86），P=0.12）。在多变量分析中，较低的充血速度与住院死亡率独立相关（每充血速度每降低1厘米/心动周期，比值比=1.11（95%置信区间=1.04至1.19）；P=0.003）。
肱动脉充血血流速度是微血管功能的无创指标，可独立预测严重脓毒症的死亡率。相比之下，反映传导动脉内皮功能的肱动脉血流介导的舒张与我们严重脓毒症队列中的死亡率无关。肱动脉充血速度可能是一种有用的测量方法，用于识别可能从旨在逆转严重脓毒症微血管功能障碍的新疗法中获益的患者，并评估这些治疗的生理疗效。
