Ketamine Flashcards
Ketamine Mechanism of Action
Antagonist of NMDA (inhibits excitatory response of glutamate), Ach antagonist in the locus coeruleus, Sodium Channel blocker, voltage gated Ca channel antagonist presynaptically, Agonist of opioid, ??Agonist of monoaminergic
Ketamine Metabolism
In liver to norketamine (decreases potency to 1/3-1/5), then hydroxylated & conjugated to water soluble & excreted
Ketamine Elimination Half Life
2-3 hours
Ketamine Excretion
> 90% renal
Ketamine CV Effects
Increase: SBP, HR, SVR
Ketamine Pulmonary Effects
No respiratory depression, increased with opioids
Ketamine CNS Effects
Increase CBF, ICP & CMRO2 (not to be used with head bleeds)
Ketamine Supplied as
10 mg/ml, 50 mg/ml, 100 mg/ml (uncommon)
Ketamine Induction dose
1-3 mg/kg IV or 4-8 mg/kg IM **
Ketamine Analgesic dose
0.2-0.5 mg/kg
Ketamine Things to be aware of
Emergence Delerium (visual, auditory, proprioceptive & confusion, premedicate with midazolam),
Ketamine Maintenance dose
30-90 mcg/kg/min without N2O
