Lidocaine Infusion Rate Calculator
Calculated Infusion Parameters:
Concentration: 0 mg/mL
Infusion Rate: 0 mL/hr
Understanding the Lidocaine Infusion Rate Calculation Formula
Lidocaine is a Class 1b anti-arrhythmic drug often administered via continuous intravenous infusion to treat ventricular arrhythmias. Because medical infusion pumps are typically programmed in milliliters per hour (mL/hr), but orders are written in milligrams per minute (mg/min), clinicians must perform a conversion calculation.
The Core Formula
To determine the pump rate, you first need to establish the concentration of the solution and then convert the time unit from minutes to hours.
Step 2: Rate (mL/hr) = [Dose (mg/min) × 60 min] / Concentration (mg/mL)
Standard Concentrations
Lidocaine is frequently supplied in premixed bags. The most common concentrations are:
- 4 mg/mL: (2 grams in 500 mL or 1 gram in 250 mL)
- 8 mg/mL: (2 grams in 250 mL)
Practical Example
If a physician orders a Lidocaine infusion at 2 mg/min using a 500 mL bag containing 2 grams (2000 mg) of Lidocaine:
- Concentration: 2000 mg / 500 mL = 4 mg/mL.
- Hourly Dose: 2 mg/min × 60 min = 120 mg/hr.
- Pump Rate: 120 mg/hr / 4 mg/mL = 30 mL/hr.
Clinical Precautions
Lidocaine toxicity is a serious risk. Monitor patients for signs of Central Nervous System (CNS) toxicity, such as tremors, slurred speech, or seizures. Always double-check calculations and pump settings, as infusion errors can lead to cardiac arrest or neurological distress. This calculator is for educational purposes and should be verified against hospital protocols.