TY - JOUR
T1 - Continuous monitoring of the Monro-Kellie doctrine
T2 - Is it possible?
AU - Kim, Dong Ju
AU - Czosnyka, Zofia
AU - Kasprowicz, Magdalena
AU - Smieleweski, Piotr
AU - Baledent, Oliver
AU - Guerguerian, Anne Marie
AU - Pickard, John D.
AU - Czosnyka, Marek
PY - 2012/5/1
Y1 - 2012/5/1
N2 - 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 Ci (combined venous and CSF compartments) were mathematically estimated using these raw signals through time series analysis; Ca and Ci were used to compute an index of cerebral compliance (ICC) as a moving correlation coefficient between C a and Ci. Conceptually, a negative ICC would represent a functional Monro-Kellie doctrine by illustrating volumetric compensations between Ca and Ci. 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.
AB - 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 Ci (combined venous and CSF compartments) were mathematically estimated using these raw signals through time series analysis; Ca and Ci were used to compute an index of cerebral compliance (ICC) as a moving correlation coefficient between C a and Ci. Conceptually, a negative ICC would represent a functional Monro-Kellie doctrine by illustrating volumetric compensations between Ca and Ci. 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.
KW - CSF compartment
KW - cerebral blood volume
KW - cerebral compliance
KW - compensatory mechanism
KW - traumatic brain injury
KW - vascular compartment
UR - http://www.scopus.com/inward/record.url?scp=84860274251&partnerID=8YFLogxK
U2 - 10.1089/neu.2011.2018
DO - 10.1089/neu.2011.2018
M3 - Article
C2 - 21895518
AN - SCOPUS:84860274251
VL - 29
SP - 1354
EP - 1363
JO - Journal of Neurotrauma
JF - Journal of Neurotrauma
SN - 0897-7151
IS - 7
ER -