Epinephrine Infusion Calculation and Dosing
Standard Preparation for Continuous Infusion
For hypotension associated with septic shock, prepare epinephrine by diluting 1 mg (1 mL of 1:1,000 solution) in 250 mL of D5W to yield a concentration of 4 mcg/mL, and infuse at an initial rate of 1-4 mcg/min (15-60 drops per minute with a microdrop apparatus), titrating up to a maximum of 10 mcg/min for adults. 1
Alternative Preparation Method
- Alternative concentration: Add 1 mg (1 mL) of epinephrine to 100 mL of saline to create a 1:100,000 solution (10 mcg/mL), administered at an initial rate of 30-100 mL/h (5-15 mcg/min), titrated based on clinical response or epinephrine side effects 1
FDA-Approved Dosing for Septic Shock
- FDA labeling: Dilute 10 mL (1 mg) of epinephrine in 1,000 mL of 5% dextrose solution to produce a 1 mcg/mL dilution 2
- Dosing range: 0.05-2 mcg/kg/min, titrated to achieve desired mean arterial pressure (MAP) 2
- Titration: Adjust every 10-15 minutes in increments of 0.05-0.2 mcg/kg/min to achieve blood pressure goal 2
- Weaning: After hemodynamic stabilization, wean incrementally over 12-24 hours by decreasing doses every 30 minutes 2
Pediatric Dosing
- Standard pediatric dose: 0.01 mg/kg (0.1 mL/kg of 1:10,000 solution; maximum dose 0.3 mg) for continuous infusion 1
- "Rule of 6" calculation: 0.6 × body weight (kg) = number of milligrams diluted to total 100 mL of saline; then 1 mL/h delivers 0.1 mcg/kg/min 1
Administration Route and Monitoring
- Venous access: Infuse into a large vein whenever possible; avoid catheter tie-in technique to prevent stasis and increased local drug concentration 2
- Avoid leg veins: Do not use leg veins in elderly patients or those with occlusive vascular disease 2
- Central access preferred: Central venous access strongly preferred for continuous infusions to minimize extravasation risk 1
Extravasation Management
- Immediate treatment: If extravasation occurs, infiltrate 5-10 mg phentolamine diluted in 10-15 mL saline at the site immediately to prevent tissue necrosis 1
- Pediatric phentolamine dose: 0.1-0.2 mg/kg up to 10 mg diluted in 10 mL of 0.9% sodium chloride 3
Critical Precautions
When to Use IV Epinephrine
Intravenous epinephrine should only be administered during cardiac arrest or to profoundly hypotensive patients who have failed to respond to IV volume replacement and several injected doses of intramuscular epinephrine, as several anaphylaxis fatalities have been attributed to injudicious use of intravenous epinephrine. 1
Monitoring Requirements
- Continuous hemodynamic monitoring is essential when available (emergency department or intensive care facility) 1
- If monitoring unavailable but IV epinephrine deemed essential, monitor by every-minute blood pressure and pulse measurements with electrocardiographic monitoring if available 1
Volume Resuscitation First
- Fluid replacement: Administer 1-2 L of normal saline to adults at 5-10 mL/kg in first 5 minutes; children can receive up to 30 mL/kg in the first hour 1
- Critical principle: Address hypovolemia with adequate crystalloid boluses before or concurrent with epinephrine administration, as vasoconstriction in hypovolemic patients causes severe organ hypoperfusion despite "normal" blood pressure 4
Drug Incompatibilities
- Never mix with alkaline solutions: Do not mix epinephrine with sodium bicarbonate or other alkaline solutions in the IV line, as epinephrine is inactivated in alkaline environments 1, 2
Common Pitfalls to Avoid
- Concentration confusion: Do not confuse 1:1,000 (1 mg/mL) with 1:10,000 (0.1 mg/mL) concentrations—using 1:1,000 IV when 1:10,000 is indicated delivers 10 times the intended dose 4
- Premature IV use: Intramuscular epinephrine (0.3-0.5 mg in anterolateral thigh) remains the preferred initial route for anaphylaxis; IV route is reserved for refractory cases with established IV access 1
- Inadequate volume resuscitation: Failure to provide aggressive crystalloid boluses concurrent with epinephrine causes severe organ hypoperfusion despite normalized blood pressure 4