What is the emergency department (ED) protocol for a patient with a medication reaction presenting with full body hives and anaphylactic symptoms?

Emergency Department Protocol for Medication Reaction with Full Body Hives and Anaphylactic Symptoms

Immediate administration of intramuscular epinephrine in the mid-outer thigh is the first-line treatment for anaphylaxis, followed by airway management, oxygen administration, IV fluid resuscitation, and adjunctive medications. 1, 2

Initial Assessment and Management (ABC Approach)

1. Immediate Actions

• Assess Airway, Breathing, Circulation (ABC) 1
• Administer epinephrine immediately via intramuscular injection in the mid-outer thigh:
  • Adults and children ≥30 kg: 0.3-0.5 mg (0.3-0.5 mL of 1:1000 solution) 1, 2, 3
  • Children <30 kg: 0.01 mg/kg, maximum 0.3 mg 1, 2
  • May repeat every 5-15 minutes if symptoms persist 1, 2
• Call for help/activate emergency response system 1
• Remove potential causative agents (medications, IV colloids, latex, chlorhexidine) 1

2. Airway Management

• Administer 100% oxygen 1
• Position patient appropriately - supine with legs elevated if hypotensive; sitting up if respiratory distress 1, 2
• Intubate if necessary for airway compromise 1

3. Circulation Support

• Establish large-bore IV access 1
• Administer IV fluids - 0.9% saline or lactated Ringer's solution at rapid rate 1, 2
• Monitor vital signs every 5-15 minutes until stable 2

Secondary Management

1. Adjunctive Medications

• Administer H1 antihistamine:

  • Adults: Chlorphenamine 10 mg IV 1
  • Children >12 years: 10 mg IV/IM
  • Children 6-12 years: 5 mg IV/IM
  • Children 6 months-6 years: 2.5 mg IV/IM
  • Children <6 months: 250 μg/kg IV/IM 1

• Administer corticosteroids:

  • Adults: Hydrocortisone 200 mg IV 1
  • Children >12 years: 200 mg IV/IM
  • Children 6-12 years: 100 mg IV/IM
  • Children 6 months-6 years: 50 mg IV/IM
  • Children <6 months: 25 mg IV/IM 1

2. Management of Persistent Symptoms

• For persistent bronchospasm: Consider salbutamol (albuterol) IV infusion, metered-dose inhaler, IV aminophylline, or magnesium sulfate 1, 2
• For persistent hypotension: Consider epinephrine infusion or alternative vasopressors (e.g., metaraminol) 1, 2

3. Laboratory Testing

• Obtain blood samples for mast cell tryptase 1:
  • Initial sample as soon as feasible after resuscitation begins
  • Second sample 1-2 hours after symptom onset
  • Third sample at 24 hours or during follow-up

Monitoring and Disposition

1. Observation

• Monitor for biphasic reactions which can occur up to 72 hours after initial reaction 2, 4
• Observe for at least 4-6 hours after symptom resolution 2
• Longer observation needed for severe reactions or those requiring multiple epinephrine doses 2

2. Disposition

• Arrange transfer to appropriate critical care area for patients with severe reactions 1
• Consider discharge only after complete resolution of symptoms and appropriate observation period 2

Discharge Planning

1. Prescriptions

• Prescribe epinephrine auto-injectors (at least 2) 2, 5
• Provide additional medications as needed (H1 antihistamines, corticosteroids) 2

2. Patient Education

• Provide anaphylaxis emergency action plan 2
• Educate on proper epinephrine auto-injector use with demonstration 2
• Instruct on recognition of anaphylaxis symptoms 2

3. Follow-up

• Arrange follow-up with primary care provider 2
• Consider referral to allergist/immunologist for identification of triggers 2

Important Considerations and Pitfalls

• Delay in epinephrine administration is associated with increased mortality and morbidity 2, 6
• Never substitute antihistamines or corticosteroids for epinephrine as first-line treatment 2
• Be aware of potential cardiac complications after epinephrine administration, especially in older adults or those with cardiovascular disease 7
• 90% of anaphylaxis cases do not require more than one epinephrine dose, but having a second dose available is important 5
• Patients on beta-blockers may have reduced response to epinephrine and may require additional interventions 2