NR 341 NERVOUS SYSTEM NOTES. | LATEST NOTES

NR 341 NERVOUS SYSTEM NOTES. Nervous System Brain and spinal cord for central nervous system. Physiology of the brain: • Our brains need constant flow of blood to supply it with glucose and oxygen. Brains get about 15% of the cardiac output. At the most, brains can withstand up to 6 minutes without oxygen before irreversible damage takes place, but this varies from person to person. • Autoregulation-Automatic adjustment of the cerebral blood vessels to maintain a constant supply of blood flow to the brain. • Low MAP, Rises in PaCO2-lead to vasodilation of cerebral vessels and increased blood flow. • High MAP, low PaCO2-lead to constriction of cerebral vessels and decreased blood flow. • Brain metabolism: • Cerebral glucose less than 70 = confusion • Cerebral glucose less than 20 = damage. • Whenever c02 level is high the brain is going to tell you to breathe fast, person will hyperventilate. Brain uses 20% of bodies oxygen and 25% of bodies glucose. Neurological assessment: We always assess brain with LOC. Neurological assessment: