Articles: brain-injuries.
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Journal of neurosurgery · Jan 1996
Characterization of edema by diffusion-weighted imaging in experimental traumatic brain injury.
The objective of this study was to use diffusion-weighted magnetic resonance imaging (DWI) to help detect the type of edema that develops after experimental trauma and trauma coupled with hypotension and hypoxia (THH). Reduction in the apparent diffusion coefficients (ADCs) is thought to represent cytotoxic edema. In a preliminary series of experiments, the infusion edema model and middle cerebral artery occlusion models were used to confirm the direction of ADC change in response to purely extracellular and cytotoxic edema, respectively. ⋯ In the trauma alone group, the rise in ICP reached a maximum value (28 +/- 3 mm Hg) at 30 minutes with a significant and sustained increase in CBF despite a gradual decrease in CPP. The ADCs in this group were not significantly reduced. The data lead the authors to suggest that the rise in ICP following severe trauma coupled with secondary insult in this model is predominately caused by cytotoxic edema and that ischemia plays a major role in the development of brain edema after head injury.
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The purpose of this study was to evaluate the effects of mannitol (Man), dexamethasone (DM), dichloroacetic acid (DCA) and 1,3-butanediol (BD) in reduction of posttraumatic cortical edema following brain deformation injury to rats. Ten minutes prior to fluid percussion injury, each animal received one of four pretreatments or placebo: Man, 1 g/kg intravenously, DM 3.0 mg/kg intravenously, DCA 25 mg/kg intraperitoneally BD 0.5 mg/kg intraperitoneally (n = 12 per treatment group), or equivolume saline (n = 8 per corresponding trauma group). Six hours after trauma, cortical tissue was harvested. ⋯ The measured cortical SpG from traumatized animals receiving Man (mean 1.037 +/- SEM .001), DCA (1.038 +/- .001), and BD (1.039 +/- .001) were equal to SpG from untraumitized cortex (1.041 +/- .001), and were significantly greater than SpG from traumatized cortex for animals receiving DM (1.035 +/- .001) or placebo (1.033 +/- .002). Pretreatment with DCA, Man, and BD appears to protect against development of posttraumatic cortical edema when measured 6 hours after blunt head trauma in the rat. Each of these chemical treatments appears effective in preventing or reducing posttraumatic cortical edema.
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Acta neurochirurgica · Jan 1996
Significance of intracranial pressure waveform analysis after head injury.
The authors have investigated the relationships between the amplitude of the ICP pulse wave, the mean values of ICP and CPP, and the outcome of 56 head injured ventilated patients. The ICP was monitored continuously using a Camino transducer (35 patients) or subdural catheter (21 patients). The mean Glasgow Coma Score was 6 (range 3-13; 5 patients had a GCS > 8 after resuscitation). ⋯ The RAP was significantly lower in patients who died or remained in the vegetative state. In 7 patients who died from uncontrollable intracranial hypertension RAP was oscillating or decreased to 0 or negative values well before brain-stem herniation. The combination of an ICP above 20 mmHg for a period longer than 6 hours with low correlation between the amplitude and pressure (RAP < 0.5) was described as an predictive index of an unfavourable outcome.
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Anesteziol Reanimatol · Jan 1996
Comparative Study[The possible mechanisms of a fibrinolytic disorder in patients with severe craniocerebral trauma].
Fibrinolysis components were studied in 32 patients with slight and 38 ones with grave craniocerebral injuries on days 1, 3, 5, and 7 after the injury. No expressed disorders of blood fibrinolytic activity were revealed in patients with slight injuries. Grave craniocerebral injuries were associated with disorders of the plasmin system. Depression of the external and internal mechanisms of fibrinolysis were the most manifest starting from day 3 and caused by a number of factors characteristic of the developing disseminated intravascular blood coagulation syndrome and, possibly, by impaired regulation of the plasmin system by the central nervous system.
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Acta neurochirurgica · Jan 1996
Arterio-jugular differences of oxygen (AVDO2) for bedside assessment of CO2-reactivity and autoregulation in the acute phase of severe head injury.
Autoregulation and CO2-reactivity can be impaired independently of each other in many brain insults, the so-called 'dissociated vasoparalysis'. The theoretical combination of preserved CO2-reactivity and impaired or abolished autoregulation can have many clinical implications in the daily management of brain injured patients. To optimize their treatment, a bedside assessment of autoregulation and CO2-reactivity is desirable. ⋯ All patients with an impaired CO2-reactivity also had an impaired autoregulation. Monitoring relative changes in AVDO2 permits a reliable study of CO2-reactivity and autoregulation at the bedside. Introducing these variables into the day-to-day management should be considered in treatment protocols.