Brain sodium, potassium, and osmolality: effects on anesthetic requirement.
We determined the effects of hyperkalemia, hypernatremia, hyperosmolality and hypo-osmolality on halothane requirement (MAC) in dogs. Hyperkalemia did not change cerebrospinal fluid potassium or MAC. Hypernatremia proportionately increased cerebrospinal fluid sodium and osmolality. MAC concomitantly increased 43%. Serum hyperosmolality achieved by administration of 12 and 25% dextrose increased cerebrospinal fluid osmolality without appreciably altering cerebrospinal fluid sodium or MAC. Infusion of 5% dextraose produced hypo-osmolality of blood and cerebrospinal fluid. Cerebrospinal fluid sodium was diluted and MAC was reduced by 24%.
D000769:Anesthesia, Inhalation; D000818:Animals; D001921:Brain / Q000378:metabolism*; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D006221:Halothane / Q000008:administration & dosage*; D006947:Hyperkalemia / Q000378:metabolism; D006955:Hypernatremia / Q000378:metabolism; D009994:Osmolar Concentration; D011188:Potassium / Q000032:analysis* / Q000134:cerebrospinal fluid; D012964:Sodium / Q000032:analysis* / Q000134:cerebrospinal fluid
D012964:Sodium; D011188:Potassium; D006221:Halothane