Pick 2-5 drugs to compare mechanism, dosing, PK, hemodynamics, side effects, and pearls. Useful for picking between induction agents, vasoactives, or NMBAs.
Propofol Diprivan | Etomidate Amidate | Ketamine Ketalar | |
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| Class | Alkylphenol IV induction agent / sedative-hypnotic | Imidazole IV induction agent | Phencyclidine derivative / NMDA antagonist |
| Mechanism | Potentiates GABA-A chloride conductance. Direct CNS depression with no analgesia. | GABA-A potentiation. Highly hemodynamically stable due to minimal SVR/contractility effects. | Non-competitive NMDA receptor antagonist. Also effects on opioid, monoaminergic, muscarinic receptors. Produces dissociative anesthesia with analgesia. |
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| PK (onset / duration) | Onset 30–45 sec. Duration 5–10 min (single bolus, redistribution). Hepatic clearance + extrahepatic. Context-sensitive half-time stays short up to 8 hr. | Onset 30–60 sec. Duration 5–10 min. Hepatic ester hydrolysis. | Onset 30 sec IV / 3–5 min IM. Duration 10–20 min IV. Hepatic CYP metabolism (norketamine metabolite still active). |
| Hemodynamics | ↓SVR + ↓preload + mild ↓contractility → ↓BP 20–30%. Blunts baroreceptor reflex; HR rise often absent or minimal. | Minimal effect — drug of choice for cardiac compromise, hypovolemia, acute trauma. | ↑BP, ↑HR, ↑CO via central sympathetic stimulation. May reveal direct cardiac depression in catecholamine-depleted patients (chronic critical illness). |
| Respiratory | Dose-dependent apnea, blunted CO₂ response. Bronchodilatory. | Less apnea than propofol. CO₂ response preserved at induction doses. | Bronchodilator. Preserves airway reflexes + spontaneous ventilation. Increased secretions (consider glycopyrrolate). |
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| Reversal | — | — | — |
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Cells showing "—" indicate the drug doesn't have a detail entry for that field yet (most drugs do; some legacy class members haven't been fully populated). Education only — verify dosing against package insert + institutional protocol before bedside use.