For an adult in cardiac arrest, how should epinephrine be prepared, diluted, and administered (dose, concentration, volume) via intravenous or intraosseous route, and what are the corresponding preparation and dosing details for pediatric patients?

ACLS Epinephrine Preparation and Administration

For adult cardiac arrest, administer 1 mg of epinephrine (1 mL of 1:10,000 solution or 0.1 mL of 1:1000 solution) intravenously or intraosseously every 3-5 minutes during CPR, with IV/IO being the mandatory first-line route. 1

Adult Cardiac Arrest Dosing

Standard Preparation and Dose

• Use 1 mg (10 mL of 1:10,000 concentration) for IV/IO administration 1
• Alternative: 0.1 mL of 1:1000 concentration equals 1 mg 1
• Maximum single dose: 1 mg (do not exceed this per administration) 1
• Repeat every 3-5 minutes throughout the resuscitation until return of spontaneous circulation or termination of efforts 1

Route Priority

• Intravenous or intraosseous routes are mandatory first-line for cardiac arrest 1
• Endotracheal administration is no longer recommended as a primary route due to unpredictable absorption and lower efficacy 1
• If IV/IO access is absolutely unavailable, endotracheal dose would be 10 times higher (10 mg or 10 mL of 1:1000), but this is a last resort 1

Administration Technique

• Push the full 10 mL volume rapidly as an IV/IO bolus 1
• Follow immediately with a 20 mL saline flush to ensure drug delivery to central circulation 1
• Minimize interruptions in chest compressions during drug administration—ideally ≤10 seconds 1
• Continue high-quality CPR while preparing and administering epinephrine 1

Pediatric Cardiac Arrest Dosing

Standard Preparation and Dose

• Dose: 0.01 mg/kg (0.1 mL/kg of 1:10,000 solution) 1
• Maximum single dose: 1 mg (10 mL) regardless of weight 1
• Repeat every 3-5 minutes during ongoing resuscitation 1

Route-Specific Considerations

• IV/IO route preferred: Use 0.01 mg/kg of 1:10,000 solution 1
• Endotracheal route (if IV/IO unavailable): Use 0.1 mg/kg of 1:1000 solution (10 times the IV dose) 1
• For neonates, IV dose is 0.01-0.03 mg/kg with endotracheal doses of 0.05-0.1 mg/kg if IV access is delayed 1

Practical Pediatric Example

• 10 kg child: 0.1 mg = 1 mL of 1:10,000 solution IV/IO 1
• 20 kg child: 0.2 mg = 2 mL of 1:10,000 solution IV/IO 1
• 40 kg child: 0.4 mg = 4 mL of 1:10,000 solution IV/IO 1
• ≥50 kg child: Use adult dose of 1 mg (10 mL) 1

Critical Preparation Details

Concentration Clarity

• 1:10,000 = 0.1 mg/mL = 1 mg in 10 mL (for IV/IO cardiac arrest) 1
• 1:1000 = 1 mg/mL (for IM anaphylaxis or endotracheal if needed) 1
• Never confuse these concentrations—using 1:1000 IV instead of 1:10,000 delivers a 10-fold overdose 1

Shelf Preparation

• Most crash carts stock pre-filled syringes of 1 mg/10 mL (1:10,000) for immediate use 1
• If drawing from ampules, draw 1 mL of 1:1000 epinephrine and dilute to 10 mL with normal saline to create 1:10,000 1
• Label syringes clearly with concentration and dose 1

Timing and Rhythm-Specific Considerations

Shockable Rhythms (VF/Pulseless VT)

• Give epinephrine after the second shock if VF/pVT persists 1
• Continue every 3-5 minutes thereafter 1
• Minimize delay between shock delivery and resumption of compressions 1

Non-Shockable Rhythms (Asystole/PEA)

• Give epinephrine as soon as IV/IO access is obtained 1
• Repeat every 3-5 minutes throughout CPR 1
• Do not delay for rhythm checks—give during ongoing compressions 1

Common Pitfalls to Avoid

Dosing Errors

• Do not use high-dose epinephrine (>1 mg in adults, >0.01 mg/kg in children)—multiple studies show no survival benefit and potential harm, particularly worse neurological outcomes 1, 2
• Do not skip doses or extend intervals beyond 5 minutes—consistent dosing every 3-5 minutes is the standard 1, 3
• Do not give epinephrine more frequently than every 3 minutes without specific indication (e.g., beta-blocker overdose) 1

Route Errors

• Do not use endotracheal route if IV/IO is available or obtainable within 1-2 minutes—endotracheal absorption is unreliable and requires 10-fold higher doses 1
• Do not delay epinephrine for central line placement—peripheral IV or IO access is sufficient and faster 1
• Do not mix epinephrine with sodium bicarbonate or other alkaline solutions in the same IV line—epinephrine is inactivated by alkalinity 4

Administration Errors

• Do not interrupt chest compressions for >10 seconds to give epinephrine—drug delivery can occur during ongoing CPR 1
• Do not forget the saline flush—without it, epinephrine may remain in the IV tubing 1
• Do not use intramuscular route for cardiac arrest—this is only for anaphylaxis 1

Special Populations

Neonatal Resuscitation

• IV dose: 0.01-0.03 mg/kg as soon as IV access is available if heart rate remains <60 bpm despite adequate ventilation and compressions 1
• Endotracheal dose: 0.05-0.1 mg/kg only if IV access is not yet available 1
• Higher IV doses (>0.03 mg/kg) are not recommended and may be harmful in neonates 1

Anaphylaxis-Induced Cardiac Arrest

• Use standard ACLS epinephrine dosing (1 mg IV/IO every 3-5 minutes) for cardiac arrest from anaphylaxis 1
• If patient has pulses but severe hypotension, use 0.05-0.1 mg IV boluses (0.5-1 mL of 1:10,000) instead of the full 1 mg 1
• For anaphylaxis without arrest, use 0.3-0.5 mg IM (1:1000) in the thigh, not IV 1

Pharmacologic Rationale

Why These Doses and Intervals

• Epinephrine's half-life is 2-3 minutes during cardiac arrest due to rapid metabolism, necessitating repeat dosing every 3-5 minutes 5
• Alpha-adrenergic effects increase coronary and cerebral perfusion pressure by peripheral vasoconstriction, which is the primary mechanism for improving ROSC 6, 5
• Beta-2 adrenergic effects may enhance cardiac pacemaker activity and myocardial contractility, distinguishing epinephrine from norepinephrine 6
• Excessive cumulative doses (>3-6 mg total) may worsen neurological outcomes after ROSC, particularly in ECPR patients, due to excessive adrenergic stimulation and microvascular injury 2

Evidence Limitations

• No RCT has definitively proven epinephrine improves neurologically intact survival in adults, though it clearly increases ROSC rates 5
• Current 3-5 minute interval is based on expert consensus, not high-quality comparative trials 3
• Studies suggest earlier administration (within first 5-10 minutes of arrest) improves outcomes compared to delayed administration 5