tailieunhanh - Neurological Emergencies - part 2

Những bệnh nhân có một khối máu tụ dưới màng cứng cấp tính được nhìn thấy sau khi vụ tai nạn giao thông đường bộ tốc độ cao, ngã, hoặc tấn công. Họ thường liên kết với các thương tích khác nhu mô, có thể ảnh hưởng đến kết quả càng nhiều như là máu tụ chính nó. | NEUROLOGICAL EMERGENCIES Figure b Patients with an acute subdural haematoma are seen after high speed road traffic accidents falls or assaults. They are commonly associated with other parenchymal injuries which may affect outcome as much as the haematoma itself. The haematoma often occurs over the temporal pole either from tearing of bridging veins or from laceration of the brain and disruption of surface arteries. The common combination of temporal lobe laceration and contusion with an associated subdural haematoma is known as burst temporal lobe disruption of autoregulation of blood flow. Penetrating injury may be clinically silent or produce focal neurological deficit due either to the haematoma or to the underlying neuronal injury. Focal contusions occur both ipsilateral and contralateral to a fracture as for example bifrontal contusions complicating an occipital fracture. As with subdural haematoma delayed deterioration may occur in a patient with a brain contusion or intraparenchymal haematoma days after the injury. 38 TRAUMATIC BRAIN INJURY Figure c Intraparenchymal haematomas occur from disruption of vascular elements. This may be focal from a penetrating injury or diffuse from rotational acceleration producing widespread haemorrhage and axonal disruption. Penetrating injur y may be clinically silent or produce focal neurological deficit due either to the haematoma or the underlying neuronal injur y. Focal contusions occur both ipsilateral and contralateral to a fracture for example bifrontal contusions complicating an occipital fracture Brain swelling and raised Intracranial pressure Intracranial pressure increases as a consequence of a rapidly developing intracranial mass lesion hypoxia hypercarbia during an epileptic seizure and in acute hydrocephalus. Brain oedema is defined as an increase in brain volume due to increase in brain water content. Klatzo defined it as vasogenic 8 because of disruption of the blood-brain barrier and escape of water