Aggarwal S, Kramer D, Yonas H, Obrist W, Kang Y, Martin M, Policare R
Department of Anesthesiology/Critical Care Medicine, School of Medicine, University of Pittsburgh, Pennsylvania 15213.
Hepatology. 1994 Jan;19(1):80-7.
The purpose of this retrospective study was to determine cerebral hemodynamic and metabolic changes in comatose patients with fulminant hepatic failure. Computerized tomography of the brain and cerebral blood flow measurements by the xenon-computerized tomography scan or intravenous xenon-133 methods were obtained in 33 patients with fulminant hepatic failure. In a subgroup of 22 patients, arteriojugular venous oxygen content difference and cerebral metabolic rate for oxygen were determined. Carbon dioxide reactivity was tested in 17 patients, and intracranial pressure was recorded by an epidural monitor in 8 patients. Cerebral blood flow and arteriojugular venous oxygen content difference were adjusted to the average arterial carbon dioxide pressure of the sample (32 mm Hg). Adjusted cerebral blood flow varied from 16.5 to 94.7 ml/100 gm/min; 52% of the patients had reduced adjusted cerebral blood flows (less than 33 ml/100 gm/min), whereas 24% had hyperemic values (greater than 50 ml/100 gm/min). Patients with higher adjusted cerebral blood flows showed cerebral swelling on computerized tomography scan (p < 0.002), were in deeper coma (p < 0.05) and had greater mortality (p < 0.002). The adjusted arteriojugular venous oxygen content difference was negatively correlated with adjusted cerebral blood flow (r = -0.61, p < 0.002). The majority of patients with reduced adjusted cerebral blood flows had low adjusted arteriojugular venous oxygen content differences (less than 5 vol%), indicating hyperemia rather than ischemia. The average cerebral metabolic rate for oxygen was 50% of normal (1.6 +/- 0.4 ml/100 gm/min); even patients with low cerebral metabolic rates for oxygen recovered neurologically.(ABSTRACT TRUNCATED AT 250 WORDS)
这项回顾性研究的目的是确定暴发性肝衰竭昏迷患者的脑血流动力学和代谢变化。对33例暴发性肝衰竭患者进行了脑部计算机断层扫描，并采用氙计算机断层扫描或静脉注射氙-133的方法测量脑血流量。在22例患者的亚组中，测定了动静脉血氧含量差和脑氧代谢率。对17例患者进行了二氧化碳反应性测试，8例患者通过硬膜外监测仪记录颅内压。将脑血流量和动静脉血氧含量差调整至样本的平均动脉二氧化碳分压（32 mmHg）。调整后的脑血流量在16.5至94.7 ml/100 gm/min之间；52%的患者调整后的脑血流量降低（低于33 ml/100 gm/min），而24%的患者脑血流量充血（高于50 ml/100 gm/min）。调整后的脑血流量较高的患者在计算机断层扫描上显示脑肿胀（p < 0.002），昏迷更深（p < 0.05），死亡率更高（p < 0.002）。调整后的动静脉血氧含量差与调整后的脑血流量呈负相关（r = -0.61，p < 0.002）。调整后的脑血流量降低的大多数患者调整后的动静脉血氧含量差较低（低于5 vol%），表明是充血而非缺血。平均脑氧代谢率为正常的50%（1.6 +/- 0.4 ml/100 gm/min）；即使是脑氧代谢率低的患者神经功能也恢复了。（摘要截短于250字）
