Intravenous glucose infusion does not decrease the sense of thirst and hunger as effectively as a carbohydrate-rich drink but does alleviate the feelings of weakness and tiredness compared with fasting.
The quantity and pattern of the blood clot on CT within the day of onset of SAH is a reliable and quick tool for locating a ruptured MCA or AcoA aneurysm. It is not, however, reliable for locating other ruptured aneurysms. Subarachnoid haemorrhage with a parenchymal hematoma is an excellent predictor of the site of a ruptured aneurysm.
Arachnoidal fibrosis following subarachnoid hemorrhage (SAH) has been suggested to play a pathogenic role in the development of late post-hemorrhagic hydrocephalus in humans. The purpose of this study was to investigate the rate of collagen synthesis in the arachnoid and the dura in the rat under normal conditions and to study the time schedule and the localization of the increased collagen synthesis following an experimental SAH. We found that the activity of prolyl 4-hydroxylase, a key enzyme in collagen synthesis, was 3-fold higher in the dura than that in the arachnoid and was similar to the activity in the skin. We then induced SAH in rats by injecting autologous arterial blood into cisterna magna. After SAH, we observed an increase in prolyl 4-hydroxylase activity of the arachnoid and the dura at 1 week. At this time point the enzyme activity in both tissues was 1.7-1.8-fold compared to that in the controls and after this time point the activities declined but remained slightly elevated at least till week 4. The rate of collagen synthesis was measured in vitro by labeling the tissues with [(3)H]proline. The rate increased to be 1.7-fold at 1 to 2 weeks after the SAH in both of the tissues. Immunohistochemically we observed a deposition of type I collagen in the meninges at 3 weeks after the SAH. SAH is followed by a transient increase in the rate of collagen synthesis in the arachnoid and, surprisingly, also the dura. Increased synthesis also resulted in an accumulation of type I collagen in the meningeal tissue, suggesting that the meninges are a potential site for fibrosis. The time schedule of these biochemical and histological events suggest that meningeal fibrosis may be involved in the pathogenesis of late post-hemorrhagic hydrocephalus.
A positive correlation was found between acute hydrocephalus and the amount of subarachnoid and, more importantly, intraventricular blood. This is consistent with the literature and confirms the current pathophysiologic concepts that the acute hydrocephalus following SAH is an obstructive form of hydrocephalus.
Procollagen propeptides increase in the CSF after subarachnoid haemorrhage, reflecting increased collagen synthesis in the arachnoid. We studied the induction of dural collagen synthesis after cerebral trauma by measuring the carboxyterminal propeptide of type I procollagen (PICP) and the aminoterminal propeptide of type III procollagen (PIIINP) in 17 subdural haematoma or effusion fluid samples obtained at operation on days 10-85 after head trauma. The concentration of PICP was 78-fold higher and that of PIIINP 156-fold higher, relative to that in the serum. These results indicate that meningeal trauma is followed by a long lasting increase in dural collagen synthesis, and suggest that enhanced synthesis of the various extracellular matrix components may have a role in the development of chronic subdural haematoma or effusion.A fluid containing space has been postulated at the dura-arachnoid junction, but many studies offer compelling evidence that no such subdural space exists.
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