Infusion Guide

⚠️ Clinical Disclaimer: These formulas are for reference only. Always double-check pump settings, line concentrations, and patient parameters against institutional protocols before administration.

Part A: Checking Patient Dose

Use this when checking a running pump to verify the drug amount received.

1 Calculate Concentration

Determine how much drug is in every milliliter of the syringe.

Conc (mg/ml) = Total Drug Amount (mg) Total Syringe Volume (ml)

2 Calculate Hourly Dose

Multiply the concentration by the current running rate.

Dose/hr = Conc × Rate (ml/hr)

3 Calculate 24-Hour Dose

Project the hourly dose over a full day.

Dose/24hr = Dose/hr × 24

4 Duration Safety Check

Ensure the remaining volume is sufficient for the intended time.

Duration = Total Volume (ml) Rate (ml/hr)
⚠️ Duration Warning

If Duration < 24 hours, the pump will empty early. Anticipate a syringe change.

Part B: Preparing a Syringe

Use this when mixing a new syringe to determine volumes and diluent needed.

1 Calculate Drug Volumes

Convert the required dose (mg) into volume (ml) using standard concentrations.

Drug Vol (ml) = Prescribed Dose Concentration

Common Concentrations

Drug Standard Conc.
Morphine10 mg/ml
Fentanyl50 mcg/ml
Hyoscine20 mg/ml
Midazolam5 mg/ml (or 1mg/ml)
Levomepromazine25 mg/ml

2 Total Drug Volume

Add the volume of every drug being added to the syringe.

Total Drug Vol = Vol A + Vol B + Vol C...

3 Calculate Diluent

Determine how much saline/water to add to reach the target syringe size.

Diluent = Target Volume - Total Drug Vol
⚠️ Volume Warning

If Total Drug Vol > Target Volume, you need a larger syringe or more concentrated drugs.

4 Set Infusion Rate

Calculate the rate to run the syringe over 24 hours.

Rate (ml/hr) = Target Volume (ml) 24 hours
Example:
22ml Syringe ÷ 24hr ≈ 0.92 ml/hr