Positive end-expiratory pressure oscillation facilitates brain vascular reactivity monitoring
Positive end-expiratory pressure oscillation facilitates brain vascular reactivity monitoring
复制标题
DOI：
10.1152/japplphysiol.00853.2012
复制
发表时间：
2012-11-01
影响因子：
3.3
通讯作者：
Rusin, Craig G.
中科院分区：
文献类型：
--
作者：
Brady, Ken M.;Easley, R. Blaine;Rusin, Craig G.
Brady Km，Easley RB，Kibler K，Kaczka DW，Andrepoulos D，Fraser CD Third，Smielewski P，Zoosnyka M，Adams GJ，Rhee CJ，Rusin CG。呼气末正压振荡有助于脑血管反应性监测。应用生理学杂志113：1362-1368,2012。2012年9月13日首次出版；DOI：10.1152/japplPhysiol.00853.2012。-压力反应性指数(Prx)确定创伤性脑损伤后的最佳脑灌流压力。我们描述了一种通过使用呼气末正压(PEEP)调制(IPRx)引起动脉血压(ABP)变化来提高PRX精确度的方法。新生猪(n=10)先进行静息呼气末呼气末正压(PEEP)，然后在5~10cmH(2)O范围内振荡，频率为1次/分。记录动脉压与颅内压之间的移动相关系数，记录动脉压在PEEP时的自发活动(频率为0.05~0.003 Hz)。IPRx也同样记录到PEEP振荡诱发的ABP波。用连续皮质激光多普勒血流量监测确定自动调节下限(LLA)。PEEP振荡提高了自动调节监测精度。PRX和iPRX的中位数绝对偏差与可能值范围的比率分别为9.5%(8.3-13.7%)和6.2%(4.2%-8.7%)(P=0.006；中位数，四分位数范围)。腹主动脉压与颅内压在左右角上方相差16 1度(15 0度~16 6度)，左右角以下相差-31度(-42°~12度，P<；0.0001)。IPRx高于LLA为-0.42(-0.67~-0.29)，低于LLA为0.32(0.22~0.43，P=0.0004)。IPRx阳性对LLA以下灌流压的特异性为97%，敏感性为91%。PEEP振荡导致稳定的低频ABP振荡，从而降低了PRX中的噪声。将这些发现安全地转换到临床环境中，有望为患者更准确、更快速地描绘出个性化的最佳灌流压目标。
Brady KM, Easley RB, Kibler K, Kaczka DW, Andropoulos D, Fraser CD 3rd, Smielewski P, Czosnyka M, Adams GJ, Rhee CJ, Rusin CG. Positive end-expiratory pressure oscillation facilitates brain vascular reactivity monitoring. J Appl Physiol 113: 1362-1368, 2012. First published September 13, 2012; doi:10.1152/japplphysiol.00853.2012.-The pressure reactivity index (PRx) identifies optimal cerebral perfusion pressure after traumatic brain injury. We describe a method to improve PRx precision by induced variations in arterial blood pressure (ABP) using positive end-expiratory pressure (PEEP) modulation (iPRx). Neonatal swine (n = 10) were ventilated with static PEEP and then with PEEP oscillated between 5 and 10 cmH(2)O at a frequency of 1/min. PRx was recorded as a moving correlation coefficient between ABP and intracranial pressure (ICP) from spontaneous ABP activity (0.05-0.003 Hz) during static PEEP. iPRx was similarly recorded with PEEP oscillation-induced ABP waves. The lower limit of autoregulation (LLA) was delineated with continuous cortical laser Doppler flux monitoring. PEEP oscillation increased autoregulation-monitoring precision. The ratios of median absolute deviations to range of possible values for the PRx and iPRx were 9.5% (8.3-13.7%) and 6.2% (4.2-8.7%), respectively (P = 0.006; median, interquartile range). The phase-angle difference between ABP and ICP above LLA was 161 degrees (150 degrees-166 degrees) and below LLA, -31 degrees (-42 degrees to 12 degrees, P < 0.0001). iPRx above LLA was -0.42 (-0.67 to -0.29) and below LLA, 0.32 (0.22-0.43, P = 0.0004). A positive iPRx was 97% specific and 91% sensitive for perfusion pressure below LLA. PEEP oscillation caused stable, low-frequency ABP oscillations that reduced noise in the PRx. Safe translation of these findings to clinical settings is expected to yield more accurate and rapid delineation of individualized optimal perfusion-pressure goals for patients.