Fluid Therapy Wizard
Step-by-step fluid therapy planning for dogs and cats.
High-risk tool. Fluid therapy requires clinical judgment. Verify calculations and monitor patient response. This wizard is for educational decision-support only.
Step 1: Patient Assessment
Enter patient details to calculate dehydration deficit.
Step 2: Fluid Needs Assessment
Calculate maintenance needs, ongoing losses, and total 24-hour plan.
Formula:
Dog: 132 × kg0.75 = — mL/day
Enter weight in Step 1 to calculate.
Total 24-hour fluid plan preview
Complete Step 1 and enter ongoing losses to see total.
Step 3: Fluid Selection
Review recommendations based on patient assessment. Select or override.
Choose a buffered isotonic crystalloid for initial hypovolemia resuscitation and most rehydration plans; tailor the exact fluid to the patient.
Blood products, colloids, and hypertonic saline are outside this wizard. Use a separate patient-specific protocol; do not base a transfusion on one PCV value alone.
Step 4: Rate Calculation
Replacement phase, maintenance phase, drip rates, and bolus volumes.
Fluid Rate Plan
Dehydration Deficit Replacement
Maintenance and Measured Ongoing Losses
Continuous Infusion (CRI) Rates
Step 5: Monitoring Plan
Track response, watch for red flags, and know when to taper.
Monitoring Checklist
Red Flags — Reassess Immediately
- Weight gain >10% above baseline or another sign of fluid accumulation
- Increased respiratory rate / effort, crackles, or cyanosis
- Progressive azotemia or decreased urine output despite fluids
- Hypertension, bounding pulses, or gallop rhythm
- Electrolyte derangement worsening (e.g. iatrogenic hypokalemia)
- Signs of volume overload in cardiac/renal patients
When to Taper Fluids
- Hydration status normalized (MM moist, CRT <2 sec, skin turgor normal)
- Stable body weight for 12–24h
- Adequate spontaneous water intake
- Electrolytes within acceptable range
- Underlying cause of losses controlled (e.g. antiemetics effective)
Fluid Plan Summary
Safety checks
- This tool supports calculation and education only.
- It does not diagnose, prescribe, or replace current clinical references.
- Verify patient-specific decisions with current fluid therapy guidelines, hospital protocols, and veterinarian judgment.
- Patients with cardiac disease, renal failure, or electrolyte disorders may require modified fluid plans.
- Monitor closely for signs of fluid overload, especially in cats and small patients.
Basis and limits
- Dehydration deficit: % dehydration × body weight (kg) × 10 = mL deficit. This is a clinical estimate; actual deficit varies with body composition and concurrent disease.
- Maintenance: This wizard uses allometric scaling (132 × kg0.75 for dogs; 80 × kg0.75 for cats). The simpler Fluid Calculator uses editable linear presets (60 mL/kg/day dogs; 40 mL/kg/day cats). Treat both as planning references and reassess against the patient.
- Deficit replacement: replace the estimated dehydration deficit over approximately 12–24 hours, adjusted for patient response, comorbidities, enteral intake, and measured ongoing losses.
- Initial hypovolemia bolus: buffered isotonic crystalloid at 15–20 mL/kg for dogs or 5–10 mL/kg for cats over 15–30 minutes, followed by endpoint reassessment before any repeat bolus.
- Drip rate: Calculated using macrodrip 20 gtt/mL. Microdrip (60 gtt/mL) yields 3× slower drop rate for the same mL/hr.
- Scope: This tool guides planning. It does not replace physical examination, diagnostics, or specialist consultation.
Formula audit trail
1. Convert weight to kg if entered in lb (lb ÷ 2.205).
2. Dehydration deficit (mL) = % dehydration × kg × 10.
3. Maintenance (mL/day) = 132 × kg0.75 (dog) or 80 × kg0.75 (cat).
4. Ongoing losses (mL) = sum of entered vomiting, polyuria, drainage, and other losses.
5. Total 24h plan (mL) = deficit + maintenance + ongoing losses.
6. Deficit replacement rate range (mL/hr) = deficit ÷ 12 hours through deficit ÷ 24 hours.
7. Maintenance and loss volume (mL) = maintenance + measured ongoing losses.
8. Maintenance and loss rate (mL/hr) = that 24-hour volume ÷ 24 hours, then adjusted to reassessment.
9. Drops/sec (macro) = (mL/hr × 20) ÷ 3600.
Calculation steps will appear here as you complete the wizard.
Related tools
Owner reviewed: September 2, 2026 · Next review: September 2, 2027, or sooner if the source guidance changes
Primary source: 2024 AAHA Fluid Therapy Guidelines for Dogs and Cats, Sections 3, 5, and 6.
Clinical correction or safety concern: Report a clinical concern. Do not send patient or client identifiers.