21 kg male baby came with supracondylar fracture of left arm.. management is percutaneous k wire fixation under GA under CArm. Anesthesiologist ordered to give baby saline but I want to know what is the amount of baby saline will be and how many drops will be that time.
Reading File
Finding Sources
Finding Sources
Finding Sources
Reading File
Reading File
I now have all the information needed. Let me calculate everything for this 21 kg child.
IV Fluid Calculation for a 21 kg Child (Perioperative Maintenance)
Step 1 — Maintenance Fluid Rate (Holliday-Segar Method)
The 4-2-1 Rule (derived from Holliday-Segar):
| Weight | Rate |
|---|---|
| First 10 kg | 4 mL/kg/hr |
| Next 10 kg (10–20 kg) | 2 mL/kg/hr |
| Each kg above 20 kg | 1 mL/kg/hr |
For a 21 kg child:
- First 10 kg → 10 × 4 = 40 mL/hr
- Next 10 kg → 10 × 2 = 20 mL/hr
- Remaining 1 kg → 1 × 1 = 1 mL/hr
Total maintenance rate = 40 + 20 + 1 = 61 mL/hr
Step 2 — Which Saline?
Per the AAP guidelines (as cited in Harriet Lane Handbook, 23rd ed.), isotonic saline (Normal Saline 0.9% or Ringer's Lactate) is now the recommended maintenance fluid for hospitalized children aged 28 days–18 years. The old practice of hypotonic ¼ NS is no longer recommended as the default.
So the baby saline (Normal Saline 0.9%) infusion is appropriate.
Step 3 — Drop Rate Calculation
Drops per minute depend on the IV set (drip factor):
For a Pediatric/Micro-drip set (60 drops/mL): (Standard for children)
$$\text{Drops/min} = \frac{\text{mL/hr} \times \text{drip factor}}{60}$$
$$= \frac{61 \times 60}{60} = \mathbf{61 \text{ drops/min}}$$
With a micro-drip set, drops/min = mL/hr numerically.
For a Standard/Macro-drip set (20 drops/mL):
$$= \frac{61 \times 20}{60} = \frac{1220}{60} \approx \mathbf{20 \text{ drops/min}}$$
For a Macro-drip set (15 drops/mL):
$$= \frac{61 \times 15}{60} = \frac{915}{60} \approx \mathbf{15–16 \text{ drops/min}}$$
Summary Table
| Parameter | Value |
|---|---|
| Child's weight | 21 kg |
| Maintenance fluid rate | 61 mL/hr |
| Fluid recommended | Normal Saline 0.9% (isotonic) |
| Drops/min (micro-drip, 60 drops/mL) | 61 drops/min |
| Drops/min (macro-drip, 20 drops/mL) | ~20 drops/min |
| Drops/min (macro-drip, 15 drops/mL) | ~15–16 drops/min |
Practical note: In pediatric surgical/GA settings, a micro-drip (burette/buretrol) set is strongly preferred for precision. At 61 mL/hr with a micro-drip set, the rate is simply 61 drops/min.
This is the maintenance rate only — the anesthesiologist may add additional fluid boluses intraoperatively to account for fasting deficit and any blood/fluid losses.
— The Harriet Lane Handbook, 23rd ed., Chapter 11: Fluids and Electrolytes
This is a shared conversation. Sign in to Orris to start your own chat.