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Crisis Card

Anaphylaxis

Stop trigger, 100% O₂, fluid bolus, EPINEPHRINE. NMBAs cause >50% of intraoperative cases.

Epinephrine 10–100 mcg IV bolus (titrate); 0.3–0.5 mg IM thigh if no IV

Recognize

  • Hypotension, tachycardia (or bradycardia preceding arrest)
  • ↑ peak airway pressure, ↓ lung compliance, wheezing
  • Hypoxia, pulmonary edema
  • Cutaneous: flushing, urticaria, periorbital/perioral edema
  • Onset usually within 3 min of trigger (faster = more severe)

Doses

Epinephrine IV
10–100 mcg bolus
Escalate to ACLS doses for arrest
Epinephrine IM
0.3–0.5 mg thigh
Repeat q5–15 min if no IV
Epi infusion
0.02–0.3 mcg/kg/min
IV fluid bolus
2–4 L crystalloid
Many liters often needed
Vasopressin
1–2 U bolus then 0.01–0.04 U/min
Diphenhydramine
0.5–1 mg/kg IV
Hydrocortisone
200 mg IV

Sequenced Actions

  1. 1
    STOP the trigger
    • NMBA, antibiotic, latex, chlorhexidine, colloid, blood product, contrast
    • Notify surgeon AND call for help
  2. 2
    100% FiO₂
    • Switch to manual ventilation; consider higher PIP for bronchospasm
    • Intubate early if angioedema present
  3. 3
    Discontinue vasodilating agents
    • Turn off volatile, stop opioid infusions
    • Give midazolam or ketamine for amnesia if hypotensive
  4. 4
    IV fluid bolus — large volume
    • 2–4 L crystalloid (or more); may need many liters
    • Treats vasodilation and capillary leak
    • Trendelenburg / leg elevation
  5. 5
    EPINEPHRINE
    • 10–100 mcg IV bolus initially; escalate as needed
    • Infusion 0.02–0.3 mcg/kg/min
    • 0.3–0.5 mg IM anterolateral thigh if no IV (repeat q5–15 min)
    • ACLS doses (0.1–1 mg IV) for cardiovascular collapse
  6. 6
    Escalate vasopressors if needed
    • Vasopressin 1–2 U bolus then 0.01–0.04 U/min infusion
    • Norepinephrine 0.02–1 mcg/kg/min
    • Methylene blue 1.5–2 mg/kg for refractory vasoplegia
  7. 7
    Treat bronchospasm
    • Inhaled albuterol via inline nebulizer
    • More epinephrine (β2 effect)
    • Consider IV magnesium sulfate 2 g over 20 min
  8. 8
    Secondary treatment (once stable)
    • H1 blocker: diphenhydramine 0.5–1 mg/kg IV
    • H2 blocker: famotidine 20 mg IV
    • Steroid: hydrocortisone 200 mg IV or methylprednisolone 1–2 mg/kg
    • Establish invasive monitoring (A-line, CVC, Foley)
  9. 9
    Diagnostics & follow-up
    • Tryptase at 1–2 h and 24 h after event
    • Document clearly (event, timing, drugs given)
    • Refer to allergist for skin testing in 4–6 weeks
    • Notify patient, PCP, pharmacy; consider MedicAlert

Common Pitfalls

  • Delaying epinephrine while giving fluids and antihistamines first.
  • Using only IM epi when IV access exists.
  • Forgetting NMBAs are #1 trigger — review all drugs administered.
  • Skipping tryptase — needed to confirm diagnosis later.

References & Further Reading

  1. 1
    Textbook

    Gaba DM, Fish KJ, Howard SK, Burden A. Crisis Management in Anesthesiology. 2nd ed. Philadelphia: Saunders/Elsevier; 2014.

  2. 2
    WebOpen source

    Stanford Anesthesia Cognitive Aid Group. Stanford Anesthesia Emergency Manual. emergencymanual.stanford.edu.

  3. 3
    Textbook

    Gropper MA, Miller RD, Cohen NH, et al., eds. Miller's Anesthesia. 9th ed. Philadelphia: Elsevier; 2020.

  4. 4
    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.

  5. 5
    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.

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