Department of Neurosurgery, Addenbrookes Hospital, University of Cambridge, Cambridge, United Kingdom.
J Neurotrauma. 2012 May 1;29(7):1354-63. doi: 10.1089/neu.2011.2018. Epub 2011 Nov 4.
The Monro-Kellie doctrine describes the principle of homeostatic intracerebral volume regulation, which stipulates that the total volume of the parenchyma, cerebrospinal fluid, and blood remains constant. Hypothetically, a slow shift (e.g., brain edema development) in the irregular vasomotion-driven exchanges of these compartmental volumes may lead to increased intracranial hypertension. To evaluate this paradigm in a clinical setting and measure the processes involved in the regulation of systemic intracranial volume, we quantified cerebral blood flow velocity (CBFv) in the middle cerebral artery, arterial blood pressure (ABP), and intracranial pressure (ICP), in 238 brain-injured subjects. Relative changes in compartmental compliances C(a) (arterial) and C(i) (combined venous and CSF compartments) were mathematically estimated using these raw signals through time series analysis; C(a) and C(i) were used to compute an index of cerebral compliance (ICC) as a moving correlation coefficient between C(a) and C(i). Conceptually, a negative ICC would represent a functional Monro-Kellie doctrine by illustrating volumetric compensations between C(a) and C(i). Clinical observations show that Lundberg A-waves and arterial hypertension were associated with negative ICC, whereas in refractory intracranial hypertension, a positive ICC was observed. In subjects who died, ICC was significantly greater than in survivors (0.46 ± 0.027 versus 0.22 ± 0.017; p<0.01) over the first 5 days of intensive care. The mortality rate is 5% when ICC is less than 0, and 43% when above 0.7. ICC above 0.7 was associated with terminally elevated ICP (chi-square p=0.026). We propose that the Monro-Kellie doctrine can be monitored in real time to illustrate the state of intracranial volume regulation.
Monro-Kellie 学说描述了脑内容量调节的内稳态原则，即实质、脑脊液和血液的总体积保持恒定。理论上，这些分隔体积的不规则血管舒缩驱动交换的缓慢转移（例如脑肿胀发展）可能导致颅内压升高。为了在临床环境中评估这一模式，并测量与系统性颅内容量调节相关的过程，我们对 238 名脑损伤患者的大脑中动脉血流速度（CBFv）、动脉血压（ABP）和颅内压（ICP）进行了量化。通过时间序列分析，从这些原始信号中数学估计了分隔顺应性 C(a)（动脉）和 C(i)（静脉和 CSF 分隔的组合）的相对变化；使用 C(a)和 C(i)计算了脑顺应性指数（ICC），作为 C(a)和 C(i)之间的移动相关系数。从概念上讲，负 ICC 将代表功能性 Monro-Kellie 学说，表明 C(a)和 C(i)之间的容积补偿。临床观察表明，Lundberg A 波和动脉高血压与负 ICC 相关，而在难治性颅内高压中，观察到正 ICC。在 ICU 前 5 天，死亡患者的 ICC 明显高于存活患者（0.46±0.027 与 0.22±0.017；p<0.01）。当 ICC 小于 0 时，死亡率为 5%，当 ICC 大于 0.7 时，死亡率为 43%。ICC 大于 0.7 与终末期颅内压升高相关（卡方检验，p=0.026）。我们提出，Monro-Kellie 学说可以实时监测，以说明颅内容量调节的状态。
