自主神经功能衰竭患者体位性血压变化期间脑氧合和血流动力学的变化

Changes in cerebral oxygenation and haemodynamics during postural blood pressure changes in patients with autonomic failure.

作者信息

Hunt Katharine, Tachtsidis Ilias, Bleasdale-Barr Katharine, Elwell Clare, Mathias Christopher, Smith Martin

机构信息

Department of Neuroanaesthesia and Neurocritical Care, The National Hospital for Neurology and Neurosurgery and Institute of Neurology, Queen Square, London WC1N 3BG, UK. Centre for Anaesthesia, University College London, UK.

出版信息

Physiol Meas. 2006 Sep;27(9):777-85. doi: 10.1088/0967-3334/27/9/002. Epub 2006 Jun 14.

DOI:10.1088/0967-3334/27/9/002

PMID:16868345

Abstract

Patients with autonomic failure suffer severe postural hypotension that may be associated with symptoms of cerebral hypoperfusion. This study utilized near-infrared spectroscopy (NIRS) to measure changes in cerebral oxygenation and haemodynamics during the head-up tilt table test in 18 patients with autonomic failure and 10 healthy age-matched volunteers. Heart rate, blood pressure (MAP), oxygen saturation, cerebral tissue oxygen index (TOI) and total cerebral haemoglobin concentration [HbT] were measured continuously. In patients with autonomic failure there was a mean (SD) reduction in MAP of 46.7 (26.5) mmHg (p < 0.005) associated with a reduction in TOI of 8.6 (6.2)% (p < 0.005) during the head-up tilt table test. In healthy volunteers mean (SD) MAP rose by 12.3 (8.0) mmHg (p < 0.005) and TOI fell by 2.6 (3.2)% (p < 0.05). There was a mean (SD) reduction in [HbT] of 3.09 (2.82) micromol l(-1) (p < 0.005) in patients, equivalent to a decrease in cerebral blood volume of 0.2 (0.18) ml/100 g. There were no changes in [HbT] in the healthy volunteers. Postural hypotension in patients with autonomic failure is associated with a substantial decrease in absolute cerebral oxygenation measured by NIRS and this might reflect a critical reduction in cerebral oxygen delivery.

摘要

自主神经功能衰竭患者会出现严重的体位性低血压，可能伴有脑灌注不足的症状。本研究利用近红外光谱技术（NIRS），对18例自主神经功能衰竭患者和10名年龄匹配的健康志愿者在头高位倾斜试验期间的脑氧合和血流动力学变化进行了测量。连续测量心率、血压（平均动脉压，MAP）、血氧饱和度、脑组织氧合指数（TOI）和全脑血红蛋白浓度[HbT]。在头高位倾斜试验期间，自主神经功能衰竭患者的平均动脉压（标准差）下降了46.7（26.5）mmHg（p<0.005），同时脑组织氧合指数下降了8.6（6.2）%（p<0.005）。在健康志愿者中，平均动脉压（标准差）上升了12.3（8.0）mmHg（p<0.005），脑组织氧合指数下降了2.6（3.2）%（p<0.05）。患者的全脑血红蛋白浓度[HbT]平均（标准差）下降了3.09（2.82）μmol l-1（p<0.005），相当于脑血容量减少了0.2（0.18）ml/100g。健康志愿者的全脑血红蛋白浓度[HbT]没有变化。自主神经功能衰竭患者的体位性低血压与通过近红外光谱技术测量的绝对脑氧合显著下降有关，这可能反映了脑氧输送的严重减少。