Everything for IV and infusion calculations on one printable page — flow rates, drip rates across all four drop factors, piggyback antibiotic rates, vasopressor infusion rates at standard concentrations, and fluid balance targets. Designed to print cleanly for a clipboard or pocket.
| Calculation | Formula |
|---|---|
| Flow rate (mL/hr) | Volume (mL) ÷ time (hours) |
| Drip rate (gtt/min) | [Volume (mL) ÷ time (min)] × drop factor |
| Infusion duration | Volume (mL) ÷ rate (mL/hr) |
| mcg/kg/min → mL/hr | (dose × kg × 60) ÷ concentration (mcg/mL) |
| Concentration (mcg/mL) | (mg in bag × 1,000) ÷ volume (mL) |
| Over | mL/hr | 10 gtt | 15 gtt | 20 gtt | 60 gtt |
|---|---|---|---|---|---|
| 4 hr | 250 | 42 | 63 | 83 | 250 |
| 6 hr | 167 | 28 | 42 | 56 | 167 |
| 8 hr | 125 | 21 | 31 | 42 | 125 |
| 10 hr | 100 | 17 | 25 | 33 | 100 |
| 12 hr | 83 | 14 | 21 | 28 | 83 |
| 24 hr | 42 | 7 | 10 | 14 | 42 |
| Volume | 15 min | 30 min | 60 min | 90 min |
|---|---|---|---|---|
| 50 mL | 200 mL/hr | 100 mL/hr | 50 mL/hr | 33 mL/hr |
| 100 mL | 400 mL/hr | 200 mL/hr | 100 mL/hr | 67 mL/hr |
| 250 mL | 1,000 mL/hr | 500 mL/hr | 250 mL/hr | 167 mL/hr |
| Drug & bag | Conc. | Dose | Rate |
|---|---|---|---|
| Dopamine 400 mg/250 mL | 1,600 mcg/mL | 5 mcg/kg/min | 13.1 mL/hr |
| Dopamine 400 mg/250 mL | 1,600 mcg/mL | 10 mcg/kg/min | 26.3 mL/hr |
| Dobutamine 250 mg/250 mL | 1,000 mcg/mL | 5 mcg/kg/min | 21.0 mL/hr |
| Nitroprusside 50 mg/250 mL | 200 mcg/mL | 0.5 mcg/kg/min | 10.5 mL/hr |
| Milrinone 20 mg/100 mL | 200 mcg/mL | 0.375 mcg/kg/min | 7.9 mL/hr |
Always confirm the concentration on the bag in front of you — it varies by unit and pharmacy. High-alert infusions need an independent double-check.
| Measure | Value |
|---|---|
| Fluid balance | Total intake − total output |
| Normal 24 hr balance | −200 to +500 mL |
| Target urine output (adult) | 0.5–1.0 mL/kg/hr (≈30–50 mL/hr) |
| Insensible losses | ≈500–1,000 mL/day (unmeasured) |
| Weight change | ≈1 kg per 1 L fluid |
Eight hours. Dividing 1,000 mL by 125 mL/hr gives 8, which is why 125 mL/hr is such a common maintenance rate — it delivers a one litre bag across a standard eight hour shift.
31 drops per minute. Working: 1,000 mL divided by 480 minutes equals 2.08 mL/min, multiplied by the 15 gtt/mL drop factor gives 31.25, rounded to 31 drops per minute.
Because a microdrip set delivers 60 drops per mL and there are 60 minutes in an hour, so the two cancel out. A rate of 100 mL/hr on a 60 gtt/mL set is exactly 100 drops per minute.