EquiCalc — Field Drug Calculator

Glucose and Fluid Calculations

GIR, maintenance rates, and glucose supplementation for equine patients.

Glucose Infusion Rate (GIR) Equine

Body Weight

Fluid Rate

Target GIR (mg/kg/min)

Dextrose Stock Concentration (%)

Bag Volume (mL)

Required Glucose Concentration–

Dextrose to Add to Bag–

Actual GIR Achieved–

Foal target: 4–6 mg/kg/min · Adult: 1–2 mg/kg/min · Max safe: ~8 mg/kg/min. Remove equal volume of saline before adding dextrose to bag.

Equine Maintenance Fluids

Body Weight

Patient Type

Dose (mL/kg/day)

mL/kg/day

Adult: 60–100 | Foal: 80–100 mL/kg/day

Maintenance Rate–

Daily Volume–

Shock Bolus (20 mL/kg)–

Adult horse maintenance: 60–100 mL/kg/day (2.5–4 mL/kg/hr). Foal: 80–100 mL/kg/day. Adjust for ongoing losses.

Dehydration Deficit

Body Weight (kg)

Estimated % Dehydration

Replacement over (hours)

Fluid Deficit–

Replacement Rate–

Total Rate (incl. maintenance)–

Holliday–Segar Fluid Calculator Pediatric / Small Equid

Body Weight

Daily Volume–

Hourly Rate–

Rate (mL/kg/hr)–

Standard Holliday–Segar rates for small equids and foals. Adjust doses above for patient-specific needs.

Holliday–Segar Reference Table

Weight Range	Daily Requirement	Hourly Rate
0–10 kg	100 mL/kg/day	4.2 mL/kg/hr
11–20 kg	1,000 + 50 mL/kg >10kg	41.7 + 2.1 mL/kg/hr
>20 kg	1,500 + 20 mL/kg >20kg	62.5 + 0.8 mL/kg/hr

Equine Quick Reference

Patient	Daily Volume	Hourly Rate	Notes
Adult Horse	60–100 mL/kg/day	2.5–4 mL/kg/hr	Adjust for sweat, GI losses
Neonatal Foal	80–100 mL/kg/day	3.3–4.2 mL/kg/hr	Higher requirement; monitor glucose
Foal (older)	60–80 mL/kg/day	2.5–3.3 mL/kg/hr	Reduce as GI function matures
Shock / Resus	20 mL/kg bolus	Repeat ×2–3 prn	Reassess after each bolus

Adjust for ongoing losses (diarrhea, sweat, nasogastric reflux). Consider colloid support if TP <4 g/dL.

Total Parenteral Nutrition

Amino acid, dextrose, and lipid calculations for equine TPN. Primarily for neonatal foals and perioperative adult horses.

TPN Component Calculator ICU

Body Weight (kg)

Patient Type

Caloric Target (kcal/kg/day)

Dextrose Concentration Available (%)

Amino Acid Solution Available (%)

Total Daily Energy–

Dextrose (60% kcal)–

Amino Acids (20% kcal → protein)–

Total TPN Volume/Day–

TPN Infusion Rate–

GIR from Dextrose–

TPN Reference

Parameter	Foal	Adult
Caloric target	50–80 kcal/kg/day	30–40 kcal/kg/day
Dextrose GIR	4–8 mg/kg/min	1–2 mg/kg/min
Amino acids	2–4 g/kg/day	1–2 g/kg/day
Lipids	1–2 g/kg/day	0.5–1 g/kg/day
Monitor glucose	q4–6h	q6–8h
Target glucose	80–140 mg/dL	80–120 mg/dL
Triglycerides	<500 mg/dL	<400 mg/dL

Start at 50% of target rate and increase over 24h. Monitor electrolytes (K, PO4, Mg) daily — refeeding syndrome risk. Dedicated catheter, change every 72h.

Constant Rate Infusions

Lidocaine, ketamine, butorphanol, morphine, and detomidine CRIs for equine pain management and anesthesia.

Lidocaine CRI Prokinetic / Analgesic

Body Weight (kg)

Loading Dose?

Target Dose (µg/kg/min)

Lidocaine Concentration

Diluent Bag (mL)

Loading Dose (1.3 mg/kg IV slow)–

Loading Dose Volume–

Lidocaine to Add to Bag–

Infusion Rate–

Give loading dose over 5–15 min. Watch for muscle fasciculations, ataxia — reduce dose. Avoid in horses with cardiac arrhythmias or seizure history.

Ketamine CRI Analgesic

Body Weight (kg)

Indication

Custom Dose (mg/kg/hr) — if custom selected

Ketamine (100 mg/mL) Volume/hr–

Dose Rate–

For TIVA: combine with guaifenesin (GKX). Sub-anesthetic ketamine reduces isoflurane requirement. Titrate to effect.

Detomidine CRI Sedation

Body Weight (kg)

Loading Dose?

CRI Target (µg/kg/hr)

Loading Dose Volume (10 mg/mL)–

CRI Dose/hr–

CRI Rate (10 mg/mL, undiluted)–

Detomidine CRI provides excellent standing sedation. Monitor HR, GI motility. Combine with butorphanol for enhanced analgesia. Yohimbine available for partial reversal.

Butorphanol CRI Opioid

Body Weight (kg)

Target Dose (µg/kg/hr)

Dose/hr–

Vol/hr (10 mg/mL)–

Butorphanol CRI reduces excitation vs. intermittent dosing. Often combined with alpha-2 CRI. Sedation/ataxia possible at high doses.

Anesthetic Drug Dosing

Induction agents, maintenance drugs, and emergency calculations for equine anesthesia.

Induction Drug Calculator Anesthesia

Body Weight

Pre-medication Level

Protocol

GKX (Triple Drip) — TIVA Anesthesia

Body Weight (kg)

Bag Volume

Guaifenesin (50 mg/mL in bag)–

Ketamine (100 mg/mL)–

Xylazine (100 mg/mL)–

Infusion Rate–

Standard GKX: 1 L guaifenesin + 2 g ketamine + 500 mg xylazine. Rate: 1–2 mL/kg/hr (55–110 mL/hr for 500 kg). Supplement with inhalant if prolonged.

Anesthetic Gas Reference

Agent	Equine MAC	Notes
Isoflurane	1.31%	Most common; cardiovascular depression dose-dependent
Sevoflurane	2.31%	Smoother recovery, expensive
Desflurane	7.6%	Rapid elimination; pungent

Adjunct	MAC Reduction
Xylazine premedication	~25%
Detomidine premedication	~30%
Ketamine CRI	~25%
Lidocaine CRI	~15–25%
Butorphanol CRI	~10%

Use multimodal analgesia to reduce inhalant requirements and improve cardiovascular function during anesthesia.

Sedation and IM Drug Doses

Standing sedation, premedication, and IM doses for the field — alpha-2 agonists, opioids, and combinations.

Alpha-2 Agonist Dosing

Body Weight

Drug

Dose–

Volume–

Concentration Used–

Opioid and Combination Doses

Body Weight (kg)

Drug

Dose–

Volume–

Notes–

Reversal Agents Emergency

Body Weight (kg)

Agent

Dose–

Volume–

Emergency and Resuscitation

Epinephrine, atropine, and emergency drug doses for equine cardiac arrest and crisis management.

Emergency Drug Doses Crash Cart

Body Weight (kg)

Dobutamine / Dopamine CRI

Body Weight (kg)

Drug

Target Dose (µg/kg/min)

Diluent Bag (mL)

Drug Concentration (stock)–

Volume to Add to Bag–

Final Concentration–

Infusion Rate–

Dobutamine is first-line for anesthesia-induced hypotension (MAP <70). Start at 1–2 µg/kg/min and titrate. Monitor HR for tachycardia.

Quick Drug Reference

Common equine drug doses, concentrations, and clinical notes.

Equine Drug Dose Reference

Drug	Route	Dose	Concentration	Notes
Xylazine	IV	0.3–1.1 mg/kg	100 mg/mL	Duration 30–45 min IV; longer IM
Detomidine	IV/IM	10–40 µg/kg IV; 40–80 µg/kg IM	10 mg/mL	Duration 60–90 min; SL gel available
Romifidine	IV	80–120 µg/kg	10 mg/mL	Less ataxia than xylazine
Butorphanol	IV/IM	0.02–0.1 mg/kg	10 mg/mL	Combine with alpha-2 for best effect
Ketamine	IV	2.2 mg/kg induction	100 mg/mL	Give after adequate sedation; don't use alone
Diazepam	IV	0.05–0.1 mg/kg	5 mg/mL	Co-induction; muscle relaxation
Midazolam	IV/IM	0.05–0.1 mg/kg	5 mg/mL	Faster onset than diazepam
Guaifenesin	IV	50–100 mg/kg to effect	50 mg/mL	Stop at buckle/knuckling; do not exceed 150 mg/kg
Propofol	IV	2–4 mg/kg	10 mg/mL	Small equids / foals only; apnea risk
Lidocaine	IV CRI	1.3 mg/kg load; 25–50 µg/kg/min	20 mg/mL (2%)	Prokinetic, analgesic, anti-inflammatory
Flunixin	IV/PO	1.1 mg/kg q12–24h	50 mg/mL	Do NOT give IM — tissue necrosis
Phenylbutazone	IV/PO	2.2–4.4 mg/kg q12–24h	200 mg/mL	Max 4.4 mg/kg/day; GI/renal risk
Meloxicam	IV/PO	0.6 mg/kg q24h	15 mg/mL (IV)	Improved GI safety profile vs. bute
Dobutamine	IV CRI	1–5 µg/kg/min	12.5 mg/mL	Anesthesia hypotension; tachycardia risk
Epinephrine	IV	0.01 mg/kg q3–5 min	1 mg/mL (1:1000)	Cardiac arrest; dilute in saline
Atropine	IV	0.01–0.02 mg/kg	0.5 mg/mL	Bradycardia/AV block; large volumes needed
Acepromazine	IV/IM	0.02–0.05 mg/kg (max 25 mg)	10 mg/mL	No analgesia; avoid in hypotensive/excited patients
Yohimbine	IV	0.075–0.15 mg/kg	2 mg/mL	Partial xylazine reversal; give slowly
Naloxone	IV	0.01–0.02 mg/kg	0.4 mg/mL	Opioid reversal; short duration — may need repeat
Calcium gluconate	IV slow	0.2–0.4 mL/kg (23% solution)	230 mg/mL	Monitor ECG; dilute 1:4 in saline
Dexamethasone	IV/IM	0.05–0.2 mg/kg	2 mg/mL	Shock, anaphylaxis, airway edema
Omeprazole	PO	4 mg/kg q24h (treatment)	37 g paste	Gastric ulcer treatment; 1 mg/kg for prevention

Normal Vitals Reference

Parameter	Adult Horse	Foal
Heart Rate	28–44 bpm	60–100 bpm
Resp Rate	8–16 rpm	20–40 rpm
Temp	37–38.5°C (99–101.5°F)	37.2–38.9°C
MAP (anesthesia)	>70 mmHg	>60 mmHg
PCV	32–52%	32–45%
TP	6–8 g/dL	4.5–7 g/dL
Glucose	80–120 mg/dL	80–140 mg/dL
Lactate	<2 mmol/L	<2 mmol/L

Common Dilutions and Stock Concentrations

Drug	Stock	Common Dilution
Lidocaine	2% (20 mg/mL)	Add to LRS for CRI
Dextrose	50% (500 mg/mL)	Add to LRS for target %
Ketamine	100 mg/mL	Add to GKX bag
Xylazine	100 mg/mL	—
Detomidine	10 mg/mL	Dilute 1:10 for CRI
Butorphanol	10 mg/mL	Dilute for CRI
Dobutamine	12.5 mg/mL	Add to 250–500 mL saline
Epinephrine	1 mg/mL (1:1000)	Dilute 1:10 for IV
Guaifenesin	50 mg/mL	Premixed or dissolve powder