How to Prepare Isoprenaline Infusion
To prepare an isoprenaline infusion, add 1-2 mg of isoprenaline to 500 mL of 5% dextrose water or normal saline to create a concentration of 2-4 mcg/mL, and administer at 0.5-5 mcg/minute initially, titrating based on patient response. 1
Standard Preparation Method
- For adult patients, add 1-2 mg of isoprenaline to 500 mL of 5% dextrose water (D5W) or normal saline to create a concentration of 2-4 mcg/mL 1
- For shock management, start at 0.5 mcg/minute and titrate gradually up to 5 mcg/minute based on patient response 1
- For bronchospasm, prepare for bolus administration of 10-20 mcg as an intravenous injection 1
Administration Considerations
- Central venous access is preferred for administration of isoprenaline to minimize risk of extravasation 2
- If central access is unavailable, peripheral IV can be used temporarily with careful monitoring 2
- Protect the infusion bottle or syringe from light by covering with protective foil to prevent medication breakdown 3
- IV tubing does not need protective foil 3
Monitoring During Infusion
- Monitor blood pressure continuously with an arterial line when possible 3
- Monitor heart rate continuously during administration 3
- Observe for potential side effects including tachycardia, arrhythmias, and hypotension 4
- Be aware that isoprenaline can paradoxically cause bradycardia in approximately 7% of patients, particularly in young patients with hypervagotonia 4
Pediatric Considerations
- For pediatric patients, the "rule of 6" can be used: 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 3
- Start at the lowest dose and titrate to desired clinical effect 3
Extravasation Management
- If extravasation occurs, inject phentolamine (0.1-0.2 mg/kg up to 10 mg diluted in 10 mL of 0.9% sodium chloride) intradermally at the extravasation site to counteract dermal vasoconstriction 3, 2
Special Considerations
- Extreme caution should be used to avoid accidental flushing or bolus injection of the IV line 3
- Isoprenaline can increase vagal activity during infusion, which may affect hemodynamic response 5
- In patients with bradyarrhythmias where external pacing is unavailable, a low-dose adrenaline (epinephrine) infusion is recommended instead of isoprenaline 3