Management of Anaphylaxis During Central Line Placement
The immediate management of anaphylaxis during central line placement requires prompt administration of intramuscular epinephrine as the first-line treatment, followed by stopping the offending agent, positioning the patient appropriately, and providing supportive care. 1
Initial Management
- Immediately administer epinephrine intramuscularly at a dose of 0.3-0.5 mg (1:1000 concentration) for adults or 0.01 mg/kg for children (maximum 0.5 mg), injected into the vastus lateralis muscle in the anterolateral thigh 1, 2
- Epinephrine may need to be repeated every 5 minutes as necessary to control symptoms and blood pressure 1, 2
- Stop the infusion or administration of the suspected triggering agent immediately 1
- Position the patient supine with legs elevated unless respiratory distress is present 2
- Establish and maintain airway; administer oxygen at 6-8 L/min 1, 2
- Establish intravenous access (if not already present) and administer fluid resuscitation with normal saline 1, 2
- Monitor vital signs closely (blood pressure, heart rate, respiratory rate, oxygen saturation) 2
Secondary Interventions
For persistent hypotension despite intramuscular epinephrine and fluid resuscitation:
- Consider intravenous epinephrine at 1:10,000 concentration (0.1 mg/mL), administered slowly 1, 2
- For protracted anaphylaxis, prepare an epinephrine infusion by adding 1 mg (1 mL) of 1:1000 dilution to 250 mL of D5W (concentration 4.0 μg/mL) and infuse at 1-4 μg/min, increasing to maximum 10 μg/min if needed 1
For patients on beta-blockers who are unresponsive to epinephrine:
Adjunctive therapies (after epinephrine administration):
- H1 antihistamines (e.g., diphenhydramine 25-50 mg IV/IM) primarily for cutaneous symptoms 1, 2
- H2 antihistamines (e.g., ranitidine 50 mg IV) may be considered, though evidence is limited 1, 2
- Glucocorticoids (e.g., methylprednisolone 1-2 mg/kg IV or prednisone 0.5 mg/kg orally) are not helpful for acute management but may be considered to prevent protracted or biphasic reactions 1
Management of Cardiopulmonary Arrest During Anaphylaxis
- Initiate cardiopulmonary resuscitation and advanced cardiac life support measures 1
- Administer high-dose intravenous epinephrine: 1-3 mg (1:10,000 dilution) slowly over 3 minutes, followed by 3-5 mg over 3 minutes, then an infusion of 4-10 μg/min 1
- Provide rapid volume expansion 1
- Consider atropine and transcutaneous pacing if asystole or pulseless electrical activity are present 1
- Prolonged resuscitation efforts are encouraged as they are more likely to be successful in anaphylaxis 1
Post-Acute Management
- Observe the patient for at least 6 hours after symptom resolution, as biphasic reactions may occur 1, 2
- The observation period should be individualized based on the severity of the reaction, with more severe reactions requiring longer observation 1, 2
- Transport to an emergency department or intensive care facility for continued monitoring 1
- After resolution, patients should receive consultation from an allergist-immunologist for evaluation of the cause and prevention strategies 1
- Provide the patient with an epinephrine auto-injector and proper instruction for self-administration in case of subsequent episodes 1, 2
Important Considerations
- Distinguish anaphylaxis from vasovagal reactions, which typically present with bradycardia rather than tachycardia and lack cutaneous manifestations (urticaria, angioedema, flushing) 1
- There are no absolute contraindications to epinephrine administration in anaphylaxis, even in patients with cardiac disease, advanced age, or frailty 1, 3
- Delay in administering epinephrine has been associated with increased mortality and risk of biphasic reactions 1, 4
- Biphasic reactions can occur up to 72 hours after the initial reaction (mean 11 hours) and are associated with greater severity of the initial reaction 1
- Early epinephrine administration may reduce the risk of biphasic reactions 1, 5