Is administering epinephrine (adrenaline) 1 milligram (mg) intravenous (IV) push appropriate in an emergent situation for a patient in cardiac arrest or severe anaphylaxis?

Epinephrine 1 mg IV Push in Emergent Situations

Administering epinephrine 1 mg IV push is appropriate and recommended for cardiac arrest, but is dangerously excessive for anaphylaxis without cardiac arrest—where the correct IV dose is only 0.05-0.1 mg (50-100 mcg), representing just 5-10% of the cardiac arrest dose. 1, 2

Critical Distinction by Clinical Scenario

For Cardiac Arrest (Any Cause)

• Standard dosing is 1 mg IV/IO every 3-5 minutes using 1:10,000 concentration (0.1 mg/mL) 1, 2
• This applies to all cardiac arrest rhythms including asystole, PEA, ventricular fibrillation, and pulseless ventricular tachycardia 1
• Early administration improves return of spontaneous circulation (ROSC), though evidence for survival to discharge or neurologically intact survival remains unclear 2

For Anaphylaxis-Induced Cardiac Arrest

• Once cardiac arrest occurs from anaphylaxis, immediately switch to standard cardiac arrest dosing: 1 mg IV/IO every 3-5 minutes 1, 2
• Standard resuscitative measures and immediate epinephrine administration take priority 1
• Some evidence suggests more aggressive dosing may be warranted: 1-3 mg IV slowly over 3 minutes initially, followed by 3-5 mg over 3 minutes, then 4-10 mg/min infusion for refractory cases 2
• A case report documented survival after accidental 10 mg epinephrine administration during anaphylaxis-induced cardiac arrest, suggesting high doses may counteract severe vasoplegic shock, though this remains anecdotal 3

For Anaphylaxis WITHOUT Cardiac Arrest

• The IV dose is dramatically lower: 0.05-0.1 mg (50-100 mcg) using 1:10,000 concentration, administered slowly 1, 2, 4
• This represents only 5-10% of the cardiac arrest dose 1
• Intramuscular administration (0.3-0.5 mg of 1:1000 concentration into the anterolateral thigh) remains the preferred first-line route due to safety, ease of administration, and rapid peak plasma concentrations 1, 2, 5
• IV epinephrine is reserved for refractory shock unresponsive to IM doses and IV fluids, or when IV access is already established 1, 2
• If IV epinephrine is used for anaphylactic shock, continuous infusion at 5-15 mcg/min is preferred over bolus dosing for better titration and avoidance of overdosing 1, 2

Critical Safety Concerns and Common Pitfalls

Medication Errors Are Life-Threatening

• Administering the cardiac arrest dose (1 mg IV) to anaphylaxis patients without cardiac arrest causes severe complications including transient systolic dysfunction, lethal arrhythmias, and cardiac arrest 6
• A survey revealed 6 of 7 hospitals did not stock prefilled IM epinephrine syringes, contributing to dosing errors 6
• Confusion between concentrations is the primary error: 1:1000 (1 mg/mL) for IM use versus 1:10,000 (0.1 mg/mL) for IV use 2, 5, 6

Preventing Errors

• Stock clearly labeled, pre-filled IM epinephrine syringes (1:1000) that are easily distinguished from IV formulations (1:10,000) 4, 6
• Use closed-loop communication and unambiguous syringe labeling during resuscitation 3
• Never administer IV epinephrine too rapidly in anaphylaxis, as this causes lethal arrhythmias 5

When Anaphylaxis Progresses Despite Treatment

Refractory Anaphylaxis

• If patients develop potentially fatal symptoms despite IM epinephrine, escalate to IV epinephrine infusion at 5-15 mcg/min with continuous hemodynamic monitoring 2, 7
• Patients can progress to cardiac arrest within minutes despite prompt recognition and standard management 7
• In one case series, 2.5% of anaphylaxis patients developed cardiac arrest despite following protocols, with 2 deaths from refractory arrest 7

Adjunctive Measures

• Aggressive IV fluid resuscitation is mandatory (1-2 liters normal saline rapidly in adults, 20 mL/kg boluses in children), as anaphylactic shock causes up to 37% loss of circulating blood volume 5
• For patients on beta-blockers with refractory hypotension, administer glucagon 1-5 mg IV over 5 minutes followed by infusion at 5-15 mcg/min 2, 5

Monitoring Requirements

• Close hemodynamic monitoring is mandatory for all patients receiving IV epinephrine due to rapid cardiovascular changes 1, 2, 4
• Observe all anaphylaxis patients for minimum 4-6 hours, as 17% experience delayed deterioration 5
• Extended observation (up to 24 hours) is warranted for severe reactions, delayed epinephrine administration, or history of biphasic reactions 5

Dose-Related Outcomes in Cardiac Arrest

• Higher cumulative epinephrine doses during CPR are strongly associated with early cardiocirculatory death after ROSC 8
• In non-shockable OHCA with ROSC, cardiocirculatory death increased linearly with cumulative doses: 17.7% with no epinephrine versus 62.5% with >10 mg 8
• This suggests potential worsening of post-resuscitation syndrome, though epinephrine remains essential for achieving ROSC 8