Acta neurochirurgica
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Acta neurochirurgica · Jan 2000
Comparative StudySystemic and cerebral haemodynamics during craniotomy under mild hypothermia in patients with acute subarachnoid haemorrhage.
Mild hypothermia provides cerebral protection against ischaemic insults in various animal models. We compared systemic and cerebral oxygenation between mild hypothermic and normothermic management in 60 patients with acute subarachnoid haemorrhage who underwent clipping of cerebral aneurysms. ⋯ The balance between oxygen supply and demand systemically and in the brain may worsen during aneurysm surgery for patients with acute subarachnoid haemorrhage under mild hypothermia. Oxygenation of the brain and the whole body should be monitored closely during this surgery, and adequate circulatory assistance is recommended under mild hypothermia.
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Acta neurochirurgica · Jan 2000
Craniocerebral war missile injuries: clinical and radiological study.
In this study we reviewed the initial clinical and radiological management and early outcomes of 176 consecutive patients from the war in Croatia.
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Acta neurochirurgica · Jan 2000
Lumbar intervertebral disc herniation following experimental intradiscal pressure increase.
An experimental biomechanical model of overload and rupture of the annulus fibrosus (AF) and lumbar disc herniation was achieved by increasing intradiscal pressure while keeping disc height constant in 69 motion segments at the L4-L5 level excised from cadaveric spines. The experiments were made on 53 specimens in neutral posture and on 16 specimens in flexion posture. ⋯ The herniated lumbar intervertebral disc model by intradiscal pressure increase makes possible these assertions: * The correlation between the degree of AF degeneration and the RIP is significant: the maximum RIP corresponds to a non-degenerated AF and the less RIP can tear only a degenerated AF; so disc herniation only occurs to discs with torn AF. * AF breaking is more often paramedian, left or right. The place of AF breaking was paramedian in 70.3% cases, median in 9.45% cases and posterolateral in 20.25% cases.
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Acta neurochirurgica · Jan 1999
Case ReportsCorrelation between jugular bulb oxygen saturation and partial pressure of brain tissue oxygen during CO2 and O2 reactivity tests in severely head-injured patients.
To correlate the jugular bulb oxygen saturation (SjvO2) and brain tissue oxygen pressure (PbtO2) during carbon dioxide (CO2) and oxygen (O2) reactivity tests in severely head-injured patients. ⋯ Correlation between SjvO2 and PbtO2 during CO2 reactivity test is low, even if significant differences between normo- and hyperventilation values are present. In comparison to SjvO2, monitoring of PbtO2 might more accurately detect possible focal ischaemic events during rapidly induced hyperventilation in severely head-injured patients. The CO2 vasoreactivity by means of changes in Vm MCA seems to be higher in comparison to changes of PbtO2. These observations lead to the hypothesis that vasoreactivity measured by TCD overestimates the cerebrovascular response to CO2.
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Acta neurochirurgica · Jan 1999
Assessment of critical closing pressure in the cerebral circulation as a measure of cerebrovascular tone.
Critical closing pressure (CCP) calculated from the blood flow velocity (FV) and arterial blood pressure (ABP) waveforms has been previously reported to be useful in the assessment of the dynamics of cerebral circulation. We investigated the relationship between CCP and intracranial pressure (ICP) and cerebrovascular tone in a model of intracranial hypertension in 22 anaesthetised New Zealand White rabbits during manipulations of arterial CO2, ABP and vasodilatation caused by hypoxia. Recordings were made of FV in the basilar artery, ABP and ICP during subarachnoid infusion of saline. ⋯ Generally, CCP decreased significantly (p<0.05) with hypercarbia, arterial hypotension and after and post-hypoxia and the difference: CCP-ICP decreased consistently after each vasodilatatory manoeuvre studied. Our data confirmed the linear relationship between CCP and ICP, and between the difference: CCP-ICP and cerebrovascular tone. However, because the magnitude of increase in ICP was not correlated to magnitude of change in CCP, CCP cannot be use for detection of increasing ICP quantitatively.