Induction

Ketamine

Phencyclidine derivative (NMDA antagonist) · Ketalar

Mechanism: Non-competitive NMDA receptor antagonist; produces dissociative anesthesia.

Calculate dose for your patient

Enter weight (kg or lb). Always verify before administration.

Patient weight

Computed weight

70.0 kg · 154.3 lb

IV induction

70 mg – 140 mg

= 1.40–2.80 mL (50 mg/mL)

IM 4–6 mg/kg. Avoid in active psychosis, severe CAD.

Analgesic infusion

7.0 mg – 35 mg

= 7.00–35.00 mL (1 mg/mL)

mg/kg/HOUR.

Weight is saved on this device for the next calculator you open.

Full dose calculator

Onset

30–60 sec IV; 3–5 min IM

Duration

10–20 min (IV)

Metabolism

Hepatic CYP450 to norketamine (active).

Dosing

Adult

Induction: 1–2 mg/kg IV or 4–6 mg/kg IM. Analgesia: 0.1–0.5 mg/kg IV.

Pediatric

Induction: 1–2 mg/kg IV or 4–6 mg/kg IM. Sedation: 0.5–1 mg/kg IV.

Indications

Induction (esp. shock, severe asthma)
Analgesia
Pediatric sedation
Bronchospasm

Contraindications

Uncontrolled HTN
Severe coronary disease (relative)
Increased ICP (controversial — modern data more permissive)
Active psychosis

Side Effects

Hypertension, tachycardia
Emergence delirium (mitigate with benzo)
Hypersalivation
Increased IOP

Clinical Pearls

1Preserves respiratory drive & airway reflexes.

2Bronchodilator — first choice for severe asthma induction.

3Co-administer midazolam or low-dose propofol to blunt emergence reactions.

References & Further Reading

1
Textbook
Flood P, Rathmell JP, Shafer S. Stoelting's Pharmacology and Physiology in Anesthetic Practice. 5th ed. Philadelphia: Wolters Kluwer; 2015.
2
Textbook
Gropper MA, Miller RD, Cohen NH, et al., eds. Miller's Anesthesia. 9th ed. Philadelphia: Elsevier; 2020.
3
Textbook
Barash PG, Cullen BF, Stoelting RK, Cahalan MK, Stock MC, Ortega R, Sharar SR, Holt NF. Clinical Anesthesia. 8th ed. Philadelphia: Wolters Kluwer; 2017.
4
Textbook
Adriano A, Morris R, eds. 2021 CA-1 Tutorial Textbook (15th Ed.). Stanford University Medical Center, Department of Anesthesiology.

Citations are provided to direct further study. Always check the most current edition of guidelines and society recommendations — the information in this chapter is a teaching summary, not primary source material.