CLEVELAND CLINIC FOUNDATION

TREATMENT OF ANAPHYLAXIS

If a serious reaction is taking place,
Call for HELP
A diagnosis of latex allergy can be suspected but almost all anesthetic agents can cause anaphylaxis. See Diagnosis of Latex Anaphylaxis.

Initial Therapy

1. Stop exposure to latex

CALL FOR THE LATEX CART
CHANGE SURGICAL GLOVES TO NON-LATEX
REMOVE LATEX CATHETERS OR OTHER INTRACAVITARY LATEX DEVICES

2. Maintain the airway and administer 100% oxygen

If a drug etiology is suspected or possible, it is preferable not to use a muscle relaxant for intubation

3. Discontinue all anesthetic agents

Inhalational agents are bronchodilators but are also CVS depressants and sensitise the myocardium to catecholamines which are required for therapy

4. Start intravascular volume expansion (2 - 4 litres of crystalloid if hypotension)

Vasodilation occurs
Up to 40% of intravascular volume may be lost into the interstitial space

5. Give EPINEPHRINE

5 - 10 ug initial bolus with hypotension, titrate as needed; 0.1 - 1 mg with cardiovascular collapse

Alpha adrenergic vasoconstriction to reverse hypotension

Beta stimulation bronchodilation and inhibition of mediator release

The dose of epinephrine depends on patient's condition. The doses given for cardiovascular collapse will cause extreme hypertension if given to normotensive or moderately hypotensive patients.

NOTE:

1. If hypotension administer epinephrine IV

2. If laryngeal edema without hypotension, administer epinephrine subcutaneously (300 - 500 ug or more)

3. Patients under spinal or epidural anesthesia may require larger doses because of sympathetic block

4. If IV access is not available, epinephrine can be given subcutaneously, in doses larger than would be administered intravenously (300 - 500 ug or more)

Secondary Therapy

1. Antihistamines (0.5 - 1 mg/kg diphenhydramine[Benadryl])

H1 receptors mediate many of the adverse effects of histamine; H1 antagonists compete with histamine at receptor sites
Inject slowly as these drugs have anti-dopaminergic effects and can cause hypotension
There is no indication for the use of H2 blockers in acute reactions

2. Catecholamine infusions

Use epinephrine (0.05 - 0.1 ug/kg/min; 2 - 4 ug/min or more) to correct hypotension
Norepinephrine (0.05 - 0.1 ug/kg/min; 2 - 4 ug/min) may rarely be required for refractory hypotension
Isoproterenol (0.01 - 0.02 ug/kg/min) can be used for severe bronchospasm, pulmonary hypertension, or right ventricular dysfunction. CAUTION in hypotensive or hypovolemic patients

3. Corticosteroids (0.25 - 1 g hydrocortisone or 1 - 2 g methylprednisolone)

May require 12 - 24 hrs to work
Unproven usefulness but usually administered ? decrease arichidonic acid metabolites, activation of inflammatory cells

4. Aminophylline (5 - 6 mg/kg over 20 minutes)

Use for persistent bronchospasm with hemodynamic stability
Bronchodilates, decreases histamine release, increases ventricular contractility, decreqases pulmonary vascular resistance

5. Albuterol (4 - 12 MDI puffs via ETT)

Bronchodilator of choice

6. Sodium bicarbonate

0.5 - 1 mEq/kg for persistent hypotension with acidosis

7. Airway evaluation

Profound laryngeal edema may occur. Do not extubate until edema subsides