Journal of neurosurgery
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Journal of neurosurgery · Jul 1992
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.
Middle cerebral artery blood flow velocity and jugular bulb venous oxygen saturation (SJO2) were measured by transcranial Doppler (TCD) ultrasonography and continuous venous oximetry, respectively, in 41 severely brain-injured patients. The purpose of the study was to examine the relationships between TCD flow velocity, SJO2, and alterations in blood pressure (BP), intracranial pressure (ICP), and cerebral perfusion pressure (CPP). In these patients, CPP was reduced either by rising ICP or by falling BP. ⋯ Transcranial Doppler ultrasonography can identify states of reduced CPP. Decreases in SJO2 with falling CPP suggested progressive failure of cerebral blood flow to meet metabolic demands. Monitoring of TCD and SJO2 may be used to define the optimum CPP level for management of severely brain-injured patients.
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Journal of neurosurgery · Jul 1992
Occlusion of the pig superior sagittal sinus, bridging and cortical veins: multistep evolution of sinus-vein thrombosis.
Cerebral sinus-vein thrombosis may lead to severe hemodynamic changes, elevated intracranial pressure (ICP), and brain edema. It is supposed that progression of the thrombus from the sinus into bridging and cortical veins plays a key role in the development of these pathophysiological changes, but this hypothesis lacks experimental proof. The aim of this study, using a novel animal model of sinus-vein thrombosis, was to evaluate the effects of a standardized occlusion of the superior sagittal sinus and its bridging and cortical veins on hemodynamic alterations, on brain water content, and on ICP in domestic pigs. ⋯ Angiography demonstrated collateral flow via cortical and bridging veins in animals with occlusion of the superior sagittal sinus alone. Additional fibrin glue obstructed these collateral vessels. The data suggest a multistep process of pathophysiological alterations in patients with sinus-vein thrombosis and may explain why these patients present with a wide variety of symptoms: minor neurological deficits or headache might indicate thrombosis of the superior sagittal sinus and/or its bridging veins.(ABSTRACT TRUNCATED AT 400 WORDS)
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Journal of neurosurgery · Jul 1992
Risk factors predicting operable intracranial hematomas in head injury.
A study was performed to examine the incidence of operable traumatic intracranial hematomas accompanying head injuries of differing degrees of severity, and to see if factors predicting operable mass lesions could be identified. Logistic analysis was used to identify independent predictors of operable traumatic intracranial hematomas. Data were gathered prospectively on 1039 patients admitted with head injury between January, 1986, and December, 1990. ⋯ There was a 29% incidence of operable intracranial hematomas for patients with a GCS score of 13 to 15, aged over 40 years and injured in a fall. It is suggested that patients who are middle-aged or older, or those injured in falls, are at particular risk for traumatic intracranial hematomas even if their GCS score is high. These patients should have early definitive investigation with computerized tomography in order to identify operable hematomas and to initiate surgical treatment prior to neurological deterioration from mass effect.