Chai Chung Liang, Tu Yong-Kwang, Huang Sheng-Jean
School of Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan, Republic of China.
J Trauma. 2008 Mar;64(3):688-97. doi: 10.1097/TA.0b013e31815ede12.
The aim of this study was to identify the precise time of occurrence of irreversible coma from brain stem dysfunction that precedes brain death. Sympathetic storm, which is a cardiovascular hyperdynamic state manifested by brain stem ischemia, is known to be related to brain stem failure in animal models. We studied sympathetic storm in the clinical setting and compared the clinical findings observed before and after sympathetic storm to identify the precise time of occurrence of irreversible apneic coma.
We conducted a retrospective study of 15 comatose traumatic brain injury adult patients at the National Taiwan University Hospital's Neurosurgical Intensive Care Unit. Data on arterial blood pressure, heart rate, intracranial pressure, and clinical findings such as cerebral blood flow pattern, Glasgow Coma Scale, brain stem reflexes, utilizations of catecholamines, and occurrence of central diabetes insipidus throughout the course in the intensive care unit were collected retrospectively from medical records.
Prolonged uncorrectable cerebral hypoperfusion was found after a characteristic irreversible apneic coma-associated sympathetic storm (IACASS) in all 15 patients. A mean cerebral perfusion pressure of 11.9 mm Hg +/- 10.3 mm Hg and 13 mm Hg +/- 3.5 mm Hg remained at 12 hours and 24 hours, respectively, after IACASS. Differences in clinical findings before and after IACASS that were statistically significant were cerebral circulation pattern (p = 0.0455), Glasgow Coma Scale (p = 0.0143), brain stem reflexes (p = 0.0143), utilization of catecholamines (p = 0.0254), and occurrence of central diabetes insipidus (p = 0.00468).
Coma might have become irreversible immediately after IACASS because the prolonged duration of cerebral hypoperfusion could have caused irreversible cerebral tissue injury. Our study provides some preliminary findings suggesting that IACASS may be a predictor of impending brain death. A prospective study is the next step to understanding whether this phenomenon can be applied clinically to diagnose irreversible apneic coma.
本研究的目的是确定脑死亡前脑干功能障碍导致不可逆昏迷的确切发生时间。交感风暴是一种由脑干缺血表现出的心血管高动力状态，在动物模型中已知与脑干衰竭有关。我们在临床环境中研究了交感风暴，并比较了交感风暴前后观察到的临床发现，以确定不可逆呼吸暂停昏迷的确切发生时间。
我们对国立台湾大学医院神经外科重症监护病房的15例昏迷创伤性脑损伤成年患者进行了回顾性研究。回顾性收集了重症监护病房整个病程中的动脉血压、心率、颅内压以及诸如脑血流模式、格拉斯哥昏迷量表、脑干反射、儿茶酚胺的使用情况和中枢性尿崩症发生情况等临床发现的数据。
在所有15例患者中，在特征性的与不可逆呼吸暂停昏迷相关的交感风暴（IACASS）后发现了持续的无法纠正的脑灌注不足。IACASS后12小时和24小时的平均脑灌注压分别为11.9 mmHg±10.3 mmHg和13 mmHg±3.5 mmHg。IACASS前后在统计学上有显著差异的临床发现是脑循环模式（p = 0.0455）、格拉斯哥昏迷量表（p = 0.0143）、脑干反射（p = 0.0143）、儿茶酚胺的使用情况（p = 0.0254）和中枢性尿崩症的发生情况（p = 0.00468）。
昏迷可能在IACASS后立即变得不可逆，因为脑灌注不足的持续时间可能导致了不可逆的脑组织损伤。我们的研究提供了一些初步发现，表明IACASS可能是即将发生脑死亡的一个预测指标。下一步是进行前瞻性研究，以了解这种现象是否可以临床应用于诊断不可逆呼吸暂停昏迷。
