Turning a selected CRI plan into mg/hr, mL/hr, and optional prepared-bag concentration math.
Clinical Tools / Live calculator
Veterinary CRI calculator
Convert a continuous-rate infusion plan into drug-per-hour and infusion-rate math. Optional dilution inputs show the final bag concentration needed over the planned duration. This tool is an arithmetic check only; verify the target rate, carrier fluid, and pump setup before clinical use.
Weight conversion, rate normalization, hourly drug requirement, and stock-concentration infusion rate.
The indication, target dose, carrier fluid, or monitoring plan for the patient in front of you.
Input
Enter the infusion plan
Enter the patient weight, selected dose rate, and stock drug concentration. Add total fluid volume and infusion duration only when you want the diluted bag concentration.
Formula
Formula audit trail
Use these steps to verify how the displayed result was calculated.
1. Convert entered weight to kg when the input is in lb.
2. Normalize the entered rate to mg/kg/hr when the source rate is written in mcg/kg/min.
3. Drug required per hour = body weight x normalized rate.
4. Infusion rate (mL/hr) = mg/hr divided by stock concentration.
5. Optional dilution math adds total drug over the selected duration, then divides by total fluid volume.
Display rounding is for readability only. Small infusion rates keep extra decimals visible so pump settings can be checked more carefully.
Calculation steps will appear here for verification.
Safety checks
Review before use
- Arithmetic support only.
- Verify the target rate, carrier fluid, and pump settings.
- Confirm final dilution, line setup, and monitoring plan before starting the infusion.
Basis
Basis and limits
- Calculation basis: weight-based CRI arithmetic with conversion to mg/hr, mL/hr, mL/min, and optional final mg/mL when dilution fields are supplied.
- Scope: this tool checks arithmetic. It does not choose the drug, target rate, dilution strategy, carrier fluid, or monitoring frequency.
- Before use: verify the final plan against current protocols, product labeling, the prepared concentration, and the actual pump setup.
Learn
Worked example and practice
Compact learning support for students, using the same arithmetic the live calculator performs.
Worked example
A 20 kg dog needs a CRI at 5 mcg/kg/min from a stock solution labeled 10 mg/mL.
5 mcg/kg/min = 0.3 mg/kg/hr
20 kg x 0.3 mg/kg/hr = 6 mg/hr
6 mg/hr / 10 mg/mL = 0.6 mL/hr
The practical readback is 0.6 mL/hr from the entered stock concentration, delivering 6 mg/hr.
Try this case
Estimate the answer before revealing it: a 4.5 kg cat has a target CRI of 0.15 mg/kg/hr and the stock concentration is 5 mg/mL.
Reveal worked answer
Drug required per hour = 4.5 kg x 0.15 mg/kg/hr = 0.675 mg/hr.
Infusion rate = 0.675 mg/hr / 5 mg/mL = 0.135 mL/hr.
This is the kind of very small rate that should trigger a pump-precision double-check.
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