Sigs Unit 8 Cases 8-15
Rationalize the use of mannitol in acute TBI. (SIGS 8.5a)
osmotic diuretic-- non-reabsorbable solute filtered by glomerulus causing water retention in PCT & dLoH-> alter Starling forces-> H20 leaves cells->decr ICP
Discuss the use of imaging in diagnosing head trauma and differentiate subdural from epidural hematoma (Sigs 8.5a)
non-contrast CT 1st; epidural: bright convex disc; subdural: crescent-shaped hemorrhage
Explain the risk of seizure and rationale for the use of fosphenytoin for seizure prophylaxis following TBI. (Sigs 8.5a)
H20-soluble prodrug metabol by plasma esterases->phenytoin->binds voltage-sensitive Na channel neuron->inhibit high-frequency repetitive action potentials