Abstract
The cerebrovascular time constant (τ) theoretically estimates how fast the cerebral arterial bed is filled by blood volume after a sudden change in arterial blood pressure during one cardiac cycle. The aim of this study was to assess the time constant of the cerebral arterial bed in patients with traumatic brain injury (TBI) with and without intracranial hematomas (IH). We examined 116 patients with severe TBI (mean 35 ± 15 years, 61 men, 55 women). The first group included 58 patients without IH and the second group included 58 patients with epidural (7), subdural (48), and multiple (3) hematomas. Perfusion computed tomography (PCT) was performed 1–12 days after TBI in the first group and 2–8 days after surgical evacuation of the hematoma in the second group. Arteriovenous amplitude of regional cerebral blood volume oscillation was calculated as the difference between arterial and venous blood volume in the “region of interest” of 1 cm2. Mean arterial pressure was measured and the flow rate of the middle cerebral artery was recorded with transcranial Doppler ultrasound after PCT. The time constant was calculated by the formula modified by Kasprowicz. The τ was shorter (p = 0.05) in both groups 1 and 2 in comparison with normal data. The time constant in group 2 was shorter than in group 1, both on the side of the former hematoma (р = 0.012) and on the contralateral side (р = 0.044). The results indicate failure of autoregulation of cerebral capillary blood flow in severe TBI, which increases in patients with polytrauma and traumatic IH.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Avezaat CJ, Eijndhoven JH (1984) Cerebrospinal fluid pulse pressure and craniospatial dynamics. A theoretical, clinical and experimental study. Erasmus University, Rotterdam
Avezaat CJ, van Eijndhoven JH (1986) Clinical observations on the relationship between cerebrospinal fluid pulse pressure and intracranial pressure. Acta Neurochir 79:13–29
Carrera E, Kim D, Castellani G (2010) Cerebral arterial compliance in patients with internal carotid artery disease. Eur J Neurol 18:711–718
Czosnyka M, Richards H, Reinhard M (2012) Cerebrovascular time constant: dependence on cerebral perfusion pressure and end-tidal carbon dioxide concentration. Neurol Res 34:17–24
Dewey R, Pierer H, Hunt WE (1974) Experimental cerebral hemodynamics. Vasomotor tone, critical closing pressure, and vascular bed resistance. J Neurosurg 41:597–606
Howlett J, Northington F (2013) Cerebrovascular autoregulation and neurologic injury in neonatal hypoxic-ischemic encephalopathy. Pediatr Res 74(5):525–535
Kasprowicz M, Diedler J, Reinhard M (2012) Time constant of the cerebral arterial bed. Acta Neurochir Suppl 114:17–21
Kasprowicz M, (2012) Assessment of cerebral hemodynamics based on pulse waveform analysis of intracranial pressure, arterial blood pressure and crerebral blood flow. Thesis, Vroclaw University, with a summary in Polish and Enlish
Kasprowicz M, Diedler J, Reinhard M (2012) Time constant of the cerebral arterial bed in normal subjects. Ultrasound Med Biol 38:1129–1137
Lassen NA (1964) Autoregulation of cerebral blood flow. Circ Res 15:201–204
ter Laan M (2014) Neuromodulation of cerebral blood flow. Proefschrift ter verkrijging van de graad van doctor, Groningen, p 125
Lewis P, Rosenfeld J (2012) Monitoring of the association between cerebral blood flow velocity and intracranial pressure. Acta Neurochir 114:147–152
Marmarou A (2007) A review of progress in understanding the pathophysiology and treatment of brain edema. Neurosurg Focus 22(5):E1
Riva N, Budohoski K, Smielewski P (2012) Transcranial Doppler Pulsatility Index: what it is and what it isn’t. Neurocrit Care 17:58–66
Shin BJ, Anumula N (2014) Does the location of the arterial input function affect quantitative CTP in patients with vasospasm? AJNR Am J Neuroradiol 35:49–54
Ursino M, Lodi C (1997) A simple mathematical model of the interaction between intracranial pressure and cerebral hemodynamics. J Appl Physiol 82:1256–1269
Varsos GV, Richards H, Kasprowicz M (2013) Cessation of diastolic cerebral blood flow velocity: the role of critical closing pressure. Neurocrit Care 20(1):40–48
Varsos GV, Richards H, Kasprowicz M (2013) Critical closing pressure determined with a model of cerebrovascular impedance. J Cereb Blood Flow Metab 33:235–243
Conflicts of Interest
We declare that we have no conflicts of interest.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2016 Springer International Publishing Switzerland
About this chapter
Cite this chapter
Trofimov, A., Kalentiev, G., Gribkov, A., Voennov, O., Grigoryeva, V. (2016). Cerebrovascular Time Constant in Patients with Head Injury. In: Applegate, R., Chen, G., Feng, H., Zhang, J. (eds) Brain Edema XVI. Acta Neurochirurgica Supplement, vol 121. Springer, Cham. https://doi.org/10.1007/978-3-319-18497-5_51
Download citation
DOI: https://doi.org/10.1007/978-3-319-18497-5_51
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-18496-8
Online ISBN: 978-3-319-18497-5
eBook Packages: MedicineMedicine (R0)