Week 7 Lesson 51 In-Class Fluids 2 Routes, Materials and Types of Fluids

Page 1: Introduction

  • Title: Systems 2: Urinary Tract and Water Balance

  • Presenters: Dr. Talia Guttin & Dr. Catherine Werners-Butler

  • PointSolutions Session ID: gouda

Page 2: Learning Outcomes

  • By end of session, students will be able to:

    • Compare and contrast different methods of fluid therapy delivery.

    • Identify materials needed for delivering fluid therapy in clinical practice.

    • Compare and contrast fluid type categories, including indications and contraindications/side effects.

Page 3: Pre-Work Check-in Questions

  • Question: Is Cocoa dehydrated, hypovolemic, or both?

    • Options:

      • A. Dehydrated

      • B. Hypovolemic

      • C. Both

Page 4: Physical Exam Indicators

  • Indicators of dehydration:

    • QAR (Quiet, Alert, Responsive)

    • Weight: 30 lbs

    • Temperature: 100F / 37.8C (normal range: 100.5-103F / 38-39.4C)

    • Pulse: 100 beats/min

    • Respiration: 44 breaths/min

    • 0 rumen contractions (abnormal)

    • Mucous membranes tacky, skin tenting 5 seconds

    • Globe recession: ~3mm

    • Sternal recumbency (needs assistance to rise)

    • Moderate suckle (not normal)

    • Specific gravity (USG): 1.045 on refractometer (high)

    • No feces observed

    • Umbilicus: dry and non-painful to palpation

    • Extremities: cold

Page 5: Hypotonic Environment Effects on Cells

  • Question: If a cell is in a hypotonic environment, what will happen?

    • Options:

      • A. Nothing

      • B. Fluid moves into the cell; the cell swells

      • C. Fluid moves out of the cell; the cell shrinks

Page 6: Hypertonic Environment Effects on Cells

  • Question: If a cell is in a hypertonic environment, what will happen?

    • Options:

      • A. Nothing

      • B. Fluid moves into the cell; the cell swells

      • C. Fluid moves out of the cell; the cell shrinks

Page 7: Routes of Fluid Delivery and Materials

  • Routes:

    • Oral (nasogastric or orogastric intubation, free drinking)

    • Subcutaneous

    • Intravenous

    • Intraosseous

    • Per rectum (horses)

  • Considerations:

    • Medical ideal

    • Cost

    • Field vs. hospital/clinic

    • Supplies available

    • Patient demeanor

Page 8: Experienced Routes of Fluid Delivery

  • Options seen:

    • A. Nasogastric oral fluids

    • B. Orogastric oral fluids

    • C. Subcutaneous fluids

    • D. Intravenous fluids

    • E. Intraosseous fluids

    • F. Fluids per rectum

Page 9: Oral Fluids

  • Types:

    • Drinking (all species)

    • Orogastric intubation (ruminants)

    • Nasogastric intubation (horses, also dogs/cats)

  • Use gastrointestinal tract if functional:

    • Protects enterocytes

    • Especially common in ruminants and horses

  • Contraindications:

    • Reflux in horses, dehydration >8%, shock, GI obstruction, rumen atony, ileus

Page 10: Materials for Nasal/Oral Intubation

  • Required materials:

    • Proper restraint (sedation, twitch, stocks)

    • Bucket

    • Water and optional electrolytes

    • Tubing

    • Pump or funnel

    • Lubricant

    • Mouth gag (cattle)

Page 11: Subcutaneous Fluids

  • Suitable for:

    • Dogs, cats, small ruminants (usually oral or IV preferred)

  • Best for mild dehydration treatment

  • Typically used in outpatient therapy:

    • Total dose: 20-30 ml/kg 1-2 times a day

    • 10 ml/kg per site

    • Calves max: 200 ml/site

Page 12: Intraosseous Fluids

  • Extension of IV space

  • Useful for small animals when IV catheter cannot be placed:

    • Includes reptiles, kittens, puppies

  • Not for large animals or birds due to pneumatic bones

Page 13: Intravenous Location Options

  • Options vary by species:

    • Jugular vein (all species)

    • Cephalic vein (SA/Equine)

    • Auricular vein (some FA)

    • Saphenous vein (SA, PBP)

    • Thoracic vein (horses)

  • Most common catheter type: Over-the-needle

Page 14: IV Catheter Sizes

  • Important factors:

    • Diameter and Length affect fluid delivery rate

    • Specific sizes:

      • Cats: 18-24 gauge

      • Dogs: 18-22 gauge

      • Camelids, small ruminants: 14-16 gauge

      • Horses, cattle: 10-16 gauge

Page 15: IV Fluid Administration Materials

  • Required materials:

    • IV fluid bag or bottle (various sizes)

    • IV line (bulb chamber, tubing, lock, cap)

      • Connects to IV catheter hub

    • Pump or manual calculation with drip set

Page 16: Factors Affecting Fluid Delivery Rate

  • Key factors:

    • A. Type of catheter (over-the-needle, butterfly, etc.)

    • B. Color

    • C. Vessel it is inserted into

    • D. Diameter and length

    • E. Material and temperature

Page 17: Catheter Complications

  • Possible complications include:

    • Thrombophlebitis

    • Hematoma

    • Extravasation

    • Overhydration

    • Catheter breaking off/chewing off

    • Blood clots in catheter

    • Infection

Page 18: Per Rectum Fluid Administration (Horses)

  • Required materials:

    • Proper restraint (sedation, twitch, stocks)

    • Water

    • Lubricant

    • 24 Fr flush enema tubing

    • Bandage (to secure tube to tail base)

    • Adapter (for tube and fluid set)

    • Coiled fluid administration set

    • 5-liter fluid bags

Page 19: Species Comparison Table Activity

  • Fill out route comparison table with species:

    • Avian, Bovine, Camelid/Caprine/Ovine, Canine, Equine, Feline, Porcine

    • Routes: Subcutaneous (SC), Intravenous (IV), Per os (PO), Intraosseous (IO), Per rectum (PR)

Page 20: Summary of Route Comparison

  • Summary of routes used:

    • SC: Yes (all listed species)

    • IV: Yes (all listed species)

    • PO: Yes (all listed species)

    • IO: Yes (all listed species)

    • PR: Yes (all listed species)

Page 21: Break Time

  • Include 10-minute break with timer for session management.

Page 22: Fluid Types

  • Options for fluids seen:

    • A. Plasmalyte-A

    • B. Normosol-R

    • C. Lactated Ringer’s Solution

    • D. 0.9% NaCl

    • E. Hypertonic saline (7.2-7.5% NaCl)

    • F. Half-strength saline (0.45% NaCl)

    • G. D5W (5% dextrose in free water)

    • H. Hetastarch

    • I. Vetstarch

    • J. Other

Page 23: Fluid Type Categories

  • Types:

    • Crystalloids: Fluid solution + electrolytes (Isotonic, Hypertonic, Hypotonic)

    • Colloids: Fluid solution + electrolytes + large osmotically active particles (Natural blood products, Synthetic)

Page 24: Colloids

  • Types:

    • Natural:

      • Pros: Replaces exactly what is missing

      • Cons: Cost, availability, transfusion reaction risk

    • Synthetic:

      • Pros: Cost-effective, readily available, fast expansion

      • Cons: Coagulopathy risk, potential for Acute Kidney Injury

Page 25: Crystalloids

  • Main fluid type for most needs:

    • Indications: Shock, maintenance, dehydration, SQ fluids

  • Pros:

    • Affordable, readily available

    • Quick yet short-lived volume expansion

    • Maintains electrolyte balance

  • Cons:

    • Moves from vasculature to interstitium after ~30 min

    • May require 3-4x as much for volume re-expansion compared to colloids

Page 26: Isotonic Crystalloids

  • Generally interchangeable with slight differences:

  • Table of fluid types and electrolyte content including:

    • 0.9% NaCl, LRS, Plasmalyte-A, Normosol-R

  • Comparison of osmolarity and electrolyte concentrations.

Page 27: Analyzing Isotonic Crystalloids

  • Identify:

    • Highest Na+: _____________

    • Highest K+: _____________

    • Highest osmolarity: _____________

    • No buffer: ________________

Page 28: Normal Plasma Sodium Levels

  • Question: What is normal plasma sodium?

    • Options:

      • A. I have no idea

      • B. 10-20 mEq/L

      • C. 25-50 mEq/L

      • D. 140-145 mEq/L

      • E. 200-250 mEq/L

Page 29: Normal Plasma Osmolarity

  • Question: What is normal plasma osmolarity, approximately?

    • Options:

      • A. I have no idea

      • B. 100 mOsm/L

      • C. 200 mOsm/L

      • D. 300 mOsm/L

      • E. 400 mOsm/L

Page 30: Hypertonic Crystalloids

  • Names: 7.2% or 7.5% NaCl (Osmolality: 2400 mOsm/L)

  • Creates osmotic gradient:

    • Pulls interstitial fluid into the intravascular space

  • Caution for dehydrated patients:

    • Must follow with crystalloid, “pay it back”

    • Used a lot in large animal fluid therapy

    • Small volume infusion needed for rapid expansion (3-5 ml/kg compared to 20 ml/kg for crystalloids)

Page 31: Hypotonic Crystalloids

  • Types:

    • Half-strength saline (0.45% NaCl), D5W

  • Osmolarity: 150-260 mOsm/L

  • CANNOT be bolused, used for maintenance only

  • Rarely used in vet med, e.g., in animals with heart failure that need fluids but can't handle normal Na+ content

Page 32: Choosing Fluid Types

  • General rule: Use balanced isotonic crystalloid unless specific needs are present.

  • Other needs examples:

    • Rapid volume expansion (large animals): Use colloid or hypertonic saline

    • Oncotic support needed: Use colloid

    • Need for red blood cells.

Page 33: Need for Oncotic Support

  • Indications for oncotic support:

    • Hypovolemia not responding to crystalloids

    • Hypoalbuminemia, or increased vascular permeability (edema, 3rd spacing fluid)

    • Transition from crystalloid to colloid may be necessary.

Page 34: Fluid Overload

  • Definitions of fluid overload:

    • Iatrogenic hypervolemia

    • Related to heart/kidney disease

  • Situations requiring oncotic support:

    • Hypoalbuminemia

    • Vasculitis/increased vascular permeability

    • Glycocalyx damage

  • Mostly a concern in small animals.

Page 35: Monitoring Fluid Therapy

  • Continuous monitoring of fluid status is essential:

  • Signs of:

    • Hypovolemia, dehydration

    • Overhydration, hypervolemia, or leaky vasculature

  • Early signs of fluid overload:

    • New heart murmur, increasing weight (1L=1kg), increased skin turgor

  • Late signs:

    • Nasal discharge, pulmonary crackles or cough, edema, effusion.

Page 36: First Choice Fluid Type

  • Question: What is the first choice fluid for almost every fluid therapy need?

    • Options:

      • A. Balanced isotonic crystalloid

      • B. Saline

      • C. Hypertonic crystalloid

      • D. Synthetic colloid

      • E. Natural colloid

Page 37: Case Study: Frenchie

  • Signalment: 3-year-old Male Neutered Terrier Mix, 15 kg

  • History: 2 days of vomiting, anorexia, diarrhea after getting into trash.

  • Physical examination findings:

    • Temperature: 101.5F

    • Pulse: 98 bpm

    • Respiration: 22 rpm

    • Mucous membranes: pink, tacky

    • CRT: 2 sec

    • Skin tent: prolonged

    • Pulses: strong

    • Blood pressure: normal

    • Extremities: warm

  • Status: Frenchie is dehydrated.

Page 38: Fluid Type for Frenchie

  • Choose fluid type:

    • A. Balanced isotonic crystalloid

    • B. Saline

    • C. Hypertonic saline

    • D. Hypotonic crystalloid

    • E. Natural colloid

    • F. Synthetic colloid

Page 39: Case Study: Bella

  • Signalment: 8-year-old Female Intact Mixed Breed Goat, non-pregnant and non-lactating.

  • History: Attacked by a dog yesterday.

  • Physical examination findings:

    • Temperature: 102.5F

    • Pulse: 140 bpm

    • Respiration: 44 rpm

    • 1 rumen contraction per 2 min

    • Mucous membranes: pink, tacky

    • CRT: 2 sec

    • Skin tent: 4 seconds

    • Pulses: strong

    • Extremities: warm

    • Injuries: Lacerations on face, nose, udder, and neck.

  • Status: Bella is dehydrated.

Page 40: Fluid Type for Bella

  • Choose fluid type:

    • A. Balanced isotonic crystalloid

    • B. Saline

    • C. Hypertonic saline

    • D. Hypotonic crystalloid

    • E. Natural colloid

    • F. Synthetic colloid

Page 41: Case Study: Ramon

  • Signalment: 4-year-old Shire Gelding, 2640 lbs.

  • History: Low-grade intermittent colic for 4 days due to pelvic flexure impaction.

  • Physical examination findings:

    • Pulse: 44 bpm

    • Respiration: 12 rpm

    • Mucous membranes: pink, slightly tacky

    • Skin tent: prolonged

    • CRT: 2 sec

    • Pulses: strong

    • Jugular fill: normal

  • Status: Ramon is dehydrated.

Page 42: Fluid Type for Ramon

  • Choose fluid type:

    • A. Balanced isotonic crystalloid

    • B. Saline

    • C. Hypertonic saline

    • D. Hypotonic crystalloid

    • E. Natural colloid

    • F. Synthetic colloid

Page 43: Review Question on Fluid Overload Signs

  • Question: What is an early clinical sign of fluid overload?

    • Options:

      • A. Increasing weight

      • B. Pitting edema

      • C. Nasal discharge

      • D. Cough

      • E. Pleural or peritoneal effusion

Page 44: Lesson Summary

  • Recap of session topics:

    • Routes of fluid delivery

    • Materials needed for different routes

    • Types of fluids with indications, pros, and cons

    • How to choose appropriate fluid types

    • Monitoring for fluid overload, hypervolemia, and oncotic support needs.