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Relationships among cerebral perfusion pressure, autoregulation, and transcranial Doppler waveform: a modeling study

Mauro Ursino, Marco Giulioni, and Carlo Alberto Lodi

the pattern of the ultrasonographic parameters, which may thus contain conflicting information and can be difficult to interpret in many pathological cases. In particular, changes in SAP and ICP, and hence in cerebral perfusion pressure ([CPP] calculated as SAP − ICP) can significantly affect the TCD waveform by two different mechanisms: alterations in transmural pressure, which are reflected in changes of vessel compliance and wall pulsatility; and alterations in CPP, which trigger the activity of the autoregulatory mechanisms. The aim of this work was to

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Intracranial hypertension and cerebral perfusion pressure: influence on neurological deterioration and outcome in severe head injury

Niels Juul, Gabrielle F. Morris, Sharon B. Marshall, the Executive Committee of the International Selfotel Trial, and Lawrence F. Marshall

greater than 1 mm; or 4) deterioration in neurological status sufficient to warrant immediate medical or surgical intervention. In the event of such an occurrence, a standardized form was completed by the investigators elucidating the circumstances, pertinent clinical and CT scan data, and the cause of the deterioration. Hypoxia was defined as PaO 2 less than 60 mm Hg and/or arterial saturation less than 85%. Shock was defined as systolic blood pressure less than 90 mm Hg. Cerebral perfusion pressure was calculated as the MAP minus the ICP. Patients in each of the

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Cerebral Perfusion Pressure and Intracranial Pressure

Neurosurgical Forum: Letters to the Editor To The Editor Harold A. Wilkinson , M.D., Ph.D. Massachusetts General Hospital Boston, Massachusetts 195 196 Abstract Object The aim of this study was to compare the effects of two different treatment protocols on physiological characteristics and outcome in patients with brain trauma. One protocol was primarily oriented toward reducing intracranial pressure (ICP), and the other primarily on maintaining cerebral perfusion pressure (CPP). Methods A series of

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Effect of head elevation on intracranial pressure, cerebral perfusion pressure, and cerebral blood flow in head-injured patients

Zeev Feldman, Malcolm J. Kanter, Claudia S. Robertson, Charles F. Contant, Christopher Hayes, Michael A. Sheinberg, Cynthia A. Villareal, Raj K. Narayan, and Robert G. Grossman

E levated intracranial pressure (ICP) or inadequate cerebral perfusion pressure (CPP) and cerebral blood flow (CBF) are common causes of secondary brain damage in head-injured patients. In patients with raised ICP, it is a common practice to position the patient in bed with the head elevated above the level of the heart. Kenning, et al. , 4 reported that elevating the head to 45° or 90° significantly reduced ICP. However, some studies suggest that head elevation may also lower the CPP. Durward, et al. , 2 studied the effect of head elevation at 0

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Pressure reactivity as a guide in the treatment of cerebral perfusion pressure in patients with brain trauma

Tim Howells, Kristin Elf, Patricia A. Jones, Elisabeth Ronne-Engström, Ian Piper, Pelle Nilsson, Peter Andrews, and Per Enblad

not statistically significant (p = 0.50). TABLE 3 Cerebral perfusion pressure insults on patient outcome * Uppsala Edinburgh Factor Low CPP Insult High CPP Insult Low CPP Insult High CPP Insult no. of patients 43 24 59 5 age (yrs) † 44 ± 17 34 ± 18 38 ± 17 51 ± 17 GCS motor score † 4.3 ± 1.2 4.8 ± 0.9 3.5 ± 1.6 3.2 ± 1.8 patients w/ GOS score (%) ‡  1 6 (14 ± 11) 2 (8) 9 (15 ± 9) 5 (100)  2–3 19 (44 ± 15) 5 (21 ± 17) 16 (27 ± 11) 0

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Determination of threshold levels of cerebral perfusion pressure and intracranial pressure in severe head injury by using receiver operating—characteristic curves: an observational study in 291 patients

Iain Robert Chambers, Lynne Treadwell, and A. David Mendelow

– S20 , 1991 Marshall LF, Marshall SB, Klauber MR, et al: A new classification of head injury based on computerized tomography. J Neurosurg 75 (Suppl): S14–S20, 1991 10.3171/sup.1991.75.1s.0s14 11. Mendelow AD , Allcutt DA , Chambers IR , et al : Intracranial and cerebral perfusion pressure monitoring in the head injured patient: Which index? in Avezaat CJJ , van Eijndhover JHM , Maas AIR (eds): Intracranial Pressure VIII. Springer-Verlag , 1993 , pp 544 – 548 Mendelow AD, Allcutt DA

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A pilot trial comparing cerebral perfusion pressure—targeted therapy to intracranial pressure—targeted therapy in children with severe traumatic brain injury

Priya Prabhakaran, Alyssa T. Reddy, W. Jerry Oakes, William D. King, Margaret K. Winkler, and Timothy G. Givens

at follow up is worse in young patients between the ages of 0 and 4 years and is best in children between the ages of 5 and 10 years. 21 At our tertiary children's hospital, a review of the experience in patients with severe TBI revealed that 47% had a poor outcome (death or persistent vegetative state), which paralleled the poor outcome rate reported by the TCDB in adults. One management strategy used to minimize secondary insults to the brain is the maintenance of adequate CPP. Cerebral perfusion pressure is the pressure gradient across the cerebral

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Is cerebral perfusion pressure a major determinant of cerebral blood flow during head elevation in comatose patients with severe intracranial lesions?

Jean-Jacques Moraine, Jacques Berré, and Christian Mélot

head injury. J Neurotrauma 9 (Suppl 1) : S333 – S348 , 1992 Bouma GJ, Muizelaar JP: Cerebral blood flow, cerebral blood volume, and cerebrovascular reactivity after severe head injury. J Neurotrauma 9 (Suppl 1): S333–S348, 1992 6. Bouma GJ , Muizelaar JP : Cerebral blood flow in severe clinical head injury. New Horiz 3 : 384 – 394 , 1995 Bouma GJ, Muizelaar JP: Cerebral blood flow in severe clinical head injury. New Horiz 3: 384–394, 1995 7. Chan KH , Miller JD , Dearden NM , et al : The effect of changes in cerebral perfusion pressure

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Pressure autoregulation monitoring and cerebral perfusion pressure target recommendation in patients with severe traumatic brain injury based on minute-by-minute monitoring data

Clinical article

Bart Depreitere, Fabian Güiza, Greet Van den Berghe, Martin U. Schuhmann, Gottlieb Maier, Ian Piper, and Geert Meyfroidt

could not demonstrate a benefit of monitoring ICP to guide intracranial hypertension management. 4 The cerebral perfusion pressure (CPP) is the pressure gradient for cerebral blood flow to the brain, expressed as the difference between the mean arterial blood pressure (MABP) and the ICP. Based on experimental and clinical work by Rosner and Daughton, 20 the original recommendation was to target CPP at 70 mm Hg or higher. A randomized trial comparing CPP-targeted therapy with ICP-targeted therapy only 19 could not demonstrate a benefit for this strategy. Moreover

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The effect of changes in cerebral perfusion pressure upon middle cerebral artery blood flow velocity and jugular bulb venous oxygen saturation after severe brain injury

Kwan-Hon Chan, J. Douglas Miller, N. Mark Dearden, Peter J. D. Andrews, and Susan Midgley

controversial. The relationships between TCD blood flow velocity, SJO 2 changes, and alterations in intracranial pressure (ICP) have not been fully defined. The present study aims to define in patients with severe brain injury the relationships of alterations in ICP, mean arterial blood pressure (MABP), and cerebral perfusion pressure (CPP) to changes in TCD blood flow velocity and SJO 2 . Clinical Material and Methods Between August, 1989, and June, 1990, 41 patients with severe closed brain injury (defined on admission as a postresuscitation Glasgow Coma Scale score