Concepts of Cerebral Perfusion Pressure and Venous Outflow Mechanism during Intracranial Hypertension

✓ Transcranial Doppler ultrasonography was used to monitor 71 patients suffering from intracranial hypertension with subsequent brain death. Among these, 29 patients were also assessed for systemic arterial pressure and epidural intracranial pressure, so that a correlation between cerebral perfusion pressure and the Doppler ultrasonography waveforms could be established. Four-vessel angiography was also performed in 33 patients after clinical brain death. With increasing intracranial pressure, the transcranial Doppler ultrasonography waveforms exhibited different characteristic high-resistance profiles with first low, then zero, and then reversed diastolic flow velocities, depending on the relationship between intracranial pressure and blood pressure (that is, cerebral perfusion pressure). This study shows that transcranial. Doppler ultrasonography may be used to assess the degree of intracranial hypertension. This technique further provides a practicable, noninvasive bedside monitor of therapeutic measures.

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Intracranial Hypertension and Cerebral Perfusion Pressure Insults in Adult Hypertensive Intraventricular Hemorrhage

Critical Care Medicine ◽

10.1097/ccm.0000000000003848 ◽

2019 ◽

Vol 47 (8) ◽

pp. 1125-1134 ◽

Cited By ~ 8

Author(s):

Wendy C. Ziai ◽

Carol B. Thompson ◽

Steven Mayo ◽

Nichol McBee ◽

William D. Freeman ◽

...

Keyword(s):

Intracranial Hypertension ◽

Cerebral Perfusion Pressure ◽

Intraventricular Hemorrhage ◽

Cerebral Perfusion ◽

Perfusion Pressure

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

Journal of Neurosurgery ◽

10.3171/jns.2000.92.1.0001 ◽

2000 ◽

Vol 92 (1) ◽

pp. 1-6 ◽

Cited By ~ 372

Author(s):

Niels Juul ◽

Gabrielle F. Morris ◽

Sharon B. Marshall ◽

_ _ ◽

Lawrence F. Marshall

Keyword(s):

Head Injury ◽

Intracranial Hypertension ◽

Cerebral Perfusion Pressure ◽

Cerebral Perfusion ◽

Severe Head Injury ◽

Perfusion Pressure ◽

Neurological Deterioration ◽

Double Blind ◽

Content Type ◽

Fine Print

Object. Recently, a renewed emphasis has been placed on managing severe head injury by elevating cerebral perfusion pressure (CPP), which is defined as the mean arterial pressure minus the intracranial pressure (ICP). Some authors have suggested that CPP is more important in influencing outcome than is intracranial hypertension, a hypothesis that this study was designed to investigate.Methods. The authors examined the relative contribution of these two parameters to outcome in a series of 427 patients prospectively studied in an international, multicenter, randomized, double-blind trial of the N-methyl-d-aspartate antagonist Selfotel. Mortality rates rose from 9.6% in 292 patients who had no clinically defined episodes of neurological deterioration to 56.4% in 117 patients who suffered one or more of these episodes; 18 patients were lost to follow up. Correspondingly, favorable outcome, defined as good or moderate on the Glasgow Outcome Scale at 6 months, fell from 67.8% in patients without neurological deterioration to 29.1% in those with neurological deterioration. In patients who had clinical evidence of neurological deterioration, the relative influence of ICP and CPP on outcome was assessed. The most powerful predictor of neurological worsening was the presence of intracranial hypertension (ICP ≥ 20 mm Hg) either initially or during neurological deterioration. There was no correlation with the CPP as long as the CPP was greater than 60 mm Hg.Conclusions. Treatment protocols for the management of severe head injury should emphasize the immediate reduction of raised ICP to less than 20 mm Hg if possible. A CPP greater than 60 mm Hg appears to have little influence on the outcome of patients with severe head injury.

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Effects of increased intracranial pressure on cerebral blood volume, blood flow, and oxygen utilization in monkeys

Journal of Neurosurgery ◽

10.3171/jns.1975.43.4.0385 ◽

1975 ◽

Vol 43 (4) ◽

pp. 385-398 ◽

Cited By ~ 138

Author(s):

Robert L. Grubb ◽

Marcus E. Raichle ◽

Michael E. Phelps ◽

Robert A. Ratcheson

Keyword(s):

Blood Flow ◽

Intracranial Pressure ◽

Metabolic Rate ◽

Intracranial Hypertension ◽

Cerebral Perfusion Pressure ◽

Blood Volume ◽

Cerebral Perfusion ◽

Cerebral Blood Volume ◽

Perfusion Pressure ◽

Cerebral Metabolic Rate

✓ The relationship of cerebral blood volume (CBV) to cerebral perfusion pressure (CPP), cerebral blood flow (CBF), and the cerebral metabolic rate for oxygen (CMRO2) was examined in rhesus monkeys. In vivo tracer methods employing radioactive oxygen-15 were used to measure CBV, CBF, and CMRO2. Cerebral perfusion pressure was decreased by raising the intracranial pressure (ICP) by infusion of artificial cerebrospinal fluid (CSF) into the cisterna magna. The production of progressive intracranial hypertension to an ICP of 70 torr (CPP of 40 torr) caused a rise in CBV accompanied by a steady CBF. With a further increase in ICP to 94 torr, CBV remained elevated without change while CBF declined significantly. Cerebral metabolic rate for oxygen did not change significantly during intracranial hypertension. For comparison, CPP was lowered by reducing mean arterial blood pressure in a second group of monkeys. Only CBF was measured in this group. In this second group of animals, the lower limit of CBF autoregulation was reached at a higher CPP (CPP ∼ 80 torr) than when an increase in ICP was employed (CPP ∼ 30 torr).

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Comment on the article ‘The Influence of Urapidil, a New Antihypertensive Agent, on Cerebral Perfusion Pressure in Dogs With and Without Intracranial Hypertension

Intensive Care Medicine ◽

10.1007/bf01692556 ◽

1983 ◽

Vol 9 (6) ◽

pp. 349-349

Author(s):

Sheila M. Willatts ◽

J. Tinker

Keyword(s):

Intracranial Hypertension ◽

Cerebral Perfusion Pressure ◽

Antihypertensive Agent ◽

Cerebral Perfusion ◽

Perfusion Pressure

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Early Craniectomy Improves Intracranial and Cerebral Perfusion Pressure after Severe Traumatic Brain Injury

The American Surgeon ◽

10.1177/000313481808400332 ◽

2018 ◽

Vol 84 (3) ◽

pp. 443-450 ◽

Cited By ~ 2

Author(s):

Casey J. Allen ◽

Daniel J. Baldor ◽

Mena M. Hanna ◽

Nicholas Namias ◽

M. Ross Bullock ◽

...

Keyword(s):

Traumatic Brain Injury ◽

Brain Injury ◽

Intracranial Hypertension ◽

Cerebral Perfusion Pressure ◽

Cerebral Perfusion ◽

Injury Severity ◽

Perfusion Pressure ◽

Daily Maximum ◽

Obvious Effect ◽

Transfusion Requirements

After traumatic brain injury, decompressive craniectomy (DC) is a second-tier, late therapy for refractory intracranial hypertension. We hypothesize that early DC, based on CT evidence of intracranial hypertension, improves intracranial pressure (ICP) and cerebral perfusion pressure (CPP). From September 2008 to January 2015, 286 traumatic brain injury patients requiring invasive ICP monitoring at a single Level I trauma center were reviewed. DC and non-DC patients were propensity score matched 1:1, based on demographics, hemodynamics, injury severity score (ISS), Glasgow Coma Scale (GCS), transfusion requirements, and need for vasopressor therapy. Data are presented as M ± SD or median (IQR) and compared at P ≤ 0.05. The study population was 42 ± 17 years, 84 per cent male, ISS = 29 ± 11, GCS = 6 (5), length of stay (LOS) = 32(40) days, and 28 per cent mortality. There were 116/286 (41%) DC, of which 105/116 (91%) were performed at the time of ICP placement. For 50 DC propensity matched to 50 non-DC patients, the midline shift was 7(11) versus 0(5) mm ( P < 0.001), abnormal ICP (hours > 20 mm Hg) was 1(10) versus 8(16) ( P = 0.017), abnormal CPP (hours < 60 mm Hg) was 0(6) versus 4(9) ( P = 0.008), daily minimum CPP (mm Hg) was 67(13) versus 62(17) ( P = 0.010), and daily maximum ICP (mm Hg) was 18(9) versus 22(11) ( P < 0.001). However, LOS [33(37) versus 25(34) days], mortality (24 versus 30%), and Glasgow Outcome Score Extended [3.0(3.0) versus 3.0(4.0)] did not improve significantly. Early DC for CT evidence of intracranial hypertension decreased abnormal ICP and CPP time and improved ICP and CPP thresholds, but had no obvious effect on the outcome.

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

Neurosurgical FOCUS ◽

10.3171/foc.1999.7.5.1 ◽

1999 ◽

Vol 7 (5) ◽

pp. E1

Author(s):

Niels Juul ◽

Gabrielle F. Morris ◽

Sharon B. Marshall ◽

_ _ ◽

Lawrence F. Marshall

Keyword(s):

Head Injury ◽

Intracranial Hypertension ◽

Cerebral Perfusion Pressure ◽

Cerebral Perfusion ◽

Severe Head Injury ◽

Perfusion Pressure ◽

Neurological Deterioration ◽

Double Blind ◽

Treatment Protocols ◽

Relative Contribution

Object Recently, a renewed emphasis has been placed on managing severe head injury by elevating cerebral perfusion pressure (CPP), which is defined as the mean arterial pressure minus the intracranial pressure (ICP). Some authors have suggested that CPP is more important in influencing outcome than is intracranial hypertension, a hypothesis that this study was designed to investigate. Methods The authors examined the relative contribution of these two parameters to outcome in a series of 427 patients prospectively studied in an international, multicenter, randomized, double-blind trial of the N-methyl-D-aspartate antagonist Selfotel. Mortality rates rose from 9.6% in 292 patients who had no clinically defined episodes of neurological deterioration to 56.5% in 117 patients who suffered one or more of these episodes; 18 patients were lost to follow up. Correspondingly, favorable outcome, defined as good or moderate on the Glasgow Outcome Scale at 6 months, fell from 67.8% in patients without neurological deterioration to 29.1% in those with neurological deterioration. In patients who had clinical evidence of neurological deterioration, the relative influence of ICP and CPP on outcome was assessed. The most powerful predictor of neurological worsening was the presence of intracranial hypertension (ICP >/= 20 mm Hg) either initially or during neurological deterioration. There was no correlation with the CPP as long as the CPP was greater than 60 mm Hg. Conclusions Treatment protocols for the management of severe head injury should emphasize the immediate reduction of raised ICP to less than 20 mm Hg if possible. A CPP greater than 60 mm Hg appears to have little influence on the outcome of patients with severe head injury.

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