Ruminant Anesthesia Flashcards by Kendra Broadfoot

physiologic consequences of general anesthesia and recumbency in ruminants (5)

-decreased GI motility, regurg
-decreased oxygenation
-decreased alveolar ventilation
-airway obstruction/aspiration
-decreased cardiac output

How well did you know this?

Not at all

Perfectly

challenges of ruminant anesthesia (4)

-restraint
-IV access
-airway moderately difficult to intubate
-in mature ruminants, almost always require ventilatory support

How well did you know this?

Not at all

Perfectly

aspects of the environment to consider for pre anesthetic prep (5)

-quiet
-safe; fences, rocks, hooks
-clean
-minimal dust/particles (eyes)
-assistance

How well did you know this?

Not at all

Perfectly

aspects of the equipment to consider for pre anesthetic prep (5)

-Halter and Rope
-Additional Ropes
-Monitoring equipment
-Pads
-Means to deliver oxygen if warrented; Oxygen tank and regulator, Oxygen tank and demand value, Oxygen tank and machine
-airway equipment

How well did you know this?

Not at all

Perfectly

pre anesthetic prep in terms of the animal (7)

-History (pregnancy status)
-PHYSICAL EXAMINATION-including weight estimation or measurement
-Pre-operative Blood Tests if necessary
-Fasting (Food and water)
-Mouth flush
-Concurrent Medications: Antibiotics, Dewormers
-IV Access: jugular, auricular vein

How well did you know this?

Not at all

Perfectly

how long to fast cows/bulls, sheep/goat, calves

Cow/Bull=24-48hrs
Sheep/Goat=12-18,
Calf=2-8hrs

How well did you know this?

Not at all

Perfectly

what to consider for the anesthetic plan (7)

-Drugs-including top-ups
-Airway Management
-Monitoring
-Supportive Measures: Pads, Oxygen with ventilatory support, Fluids
-Emergency Preparation
-Post operative analgesia
-Drug withdrawal times

How well did you know this?

Not at all

Perfectly

pre anesthetic medication options for ruminants, whats the most common

Alpha-2 Adrenergic Agonists-(most common); Xylazine
Phenothiazines; Acepromazine
Benzodiazepines (Unreliable IM); Diazepam, Midazolam
Opioids
Combinations

How well did you know this?

Not at all

Perfectly

what cant you use for premed in ruminants

anticholinergics

How well did you know this?

Not at all

Perfectly

overall benefits of xylazine as a premed

– Excellent quality of sedation: reliable, predictable, dose-dependent
– Reversible
– Analgesic

How well did you know this?

Not at all

Perfectly

side effects of xylazine

Hypoxemia (sheep/goats!)
Respiratory Depression
Typany (Ileus)
Bradycardia
Salivation
Hyperglycemia, Diuresis
Increase uterine tone

How well did you know this?

Not at all

Perfectly

contraindications of xylazine

Debilitated
Hypoxemic, Hypovolemic
Urinary Obstruction
3rd Trimester of Pregnancy

How well did you know this?

Not at all

Perfectly

what species is most sensitive vs most resistant to xylazine

resistant = swine
sensitive = goats

How well did you know this?

Not at all

Perfectly

overall features of ace as a premed

– Associated with less profound sedation than xylazine
– No analgesia
– No reversal agent available

How well did you know this?

Not at all

Perfectly

side effects of ace as a premed

Hypotension
Regurgitation

How well did you know this?

Not at all

Perfectly

when to avoid ace as a premed in ruminants

hypovolemic patients

general features of diazepam/midazolam as a premed, and how to give

Not routinely used as sedative in adult bovine; Minimal calming, large volume required
Induces moderate sedation in calves or sick adult ruminants
Diazepam should not be given IM
Midazolam can be given IM

anticholinergics as a premed, what its used for

Not routinely utilized
– Increase viscosity of secretions
– Little efficacy on reducing volume of secretions
Indicated to treat bradycardia
– Glycopyrrolate preferred over atropine
Longer duration of action
Less placental transfer

options for induction (4)

– Ketamine and Diazepam
– Ketamine
– Guaifenesin (GG) and Ketamine
– Propofol (small ruminants, calves)

IV maintenance options

Intravenous
* Triple Drip – Xylazine/Guaifenesin/Ketamine
* Repeat boluses of injectable agents

general rule for airway management in ruminants

Any domestic ruminant placed under general anesthesia = should have airway protected (even if you are going to maintain with an
injectable anesthetic)

why is it challenging to get an airway in ruminants

Anatomy:
* Tongue
* Jaw mobility
* Larynx position-caudal and sloping
* Goats with horns…sometimes hard to position head

Right main stem bronchus
-Significance: watch endotracheal tube length in calves, sheep and goats

oxygen delivery options for ruminants

Anesthetic Machine and tank (with
regulator)
Demand valve and tank (with regulator)
Flow meter and tank (with regulator)

techniques for airway manangement (4)

– Blind Intubation: sheep and calves
– Direct Visualization: sheep and calves
– Palpation: mature bovine
– Fiberoptic intubation

anesthetic drug plans for the healthy cow/bull; plan 1 vs plan 2

Plan 1: – Premedication: Xylazine – Induction: GG and Ketamine – Maintenance: Inhalant or GXK Plan 2: – Premedication: Xylazine – Induction: Diazepam/Ketamine – Maintenance: Inhalant or GXK

anesthetic drug plans for calf; plan 1 vs plan 2

Plan 1: – Premedication: Diazepam – Induction: Ketamine – Maintenance: Inhalant or GXK or propofol cri or bolus ketamine Plan 2: – Premedication: Xylazine – Induction: Ketamine ± Benzodiazepine – Maintenance: Inhalant or GXK or propofol cri or bolus ketamine

anesthetic drug plans for sheep; plan 1 vs plan 2

Plan 1: – Premedication: Xylazine, Acepromazine, Benzodiazepine or None – Induction: Ketamine ± Benzodiazepine – Maintenance: Inhalant Plan 2: – Premedication: Xylazine, Acepromazine, Benzodiazepine or None – Induction: Propofol ± Benzodiazepine – Maintenance: Inhalant

how to determine depth of anesthesia (4)

1. Eyes; Position, Reflexes, Tearing 2. Muscle Tone, Movement 3. Respiratory Pattern 4. Cardiovascular System

specific features to look at for CV system for monitoring depth of anesthesia

1. HR 2. Heart Rhythm 3. MM Color 4. CRT 5. Blood Pressure

specific features to look at for respiratory system for monitoring depth of anesthesia

1. Rate 2. Respiratory Pattern 3. MM color 4. Hemoglobin Saturation-Pulse Oximeter 5. End Tidal CO2 6. PaCO2, PaO2

supportive measures for anesthesia

* Padding * Positioning-raise the occiput, allow drainage of mouth * Adult cows-consider placing tube into rumen (ororuminal) * oxygen * fluids

recovery plan (3)

* Examine Airway: Remove Debris * Maintain Airway until sternal and strong swallowing reflex * Extubate with cuff partially inflated

Complications Associated with Anesthesia in the Ruminant during induction

1. Regurgitation Prevention: Off-feed Treatment: Position to minimize risk of aspiration 2. Aspiration Prevention: Off-feed, Airway protection Treatment: Suction airway, supportive management

Complications Associated with Anesthesia in the Ruminant during maintenance

1. Hypoventilation (inc PaCO2) Etiologies: Drugs, Excessive Depth Treatment: Change Anesthetic Depth, IPPV 2. Hypoxia (dec PaO2) Etiologies: dec PAO2, dec Lung Volume- (FRC), dec CO Treatment: inc FiO2, dec Depth, IPPV, inc CO 3. Bloat Prevention: Off-feed Treatment: Place tube into rumen (ororuminal) after airway secured, Deflate percutaneously

Complications Associated with Anesthesia in the Ruminant during recovery

1. Neuropathy Etiologies: Drugs, Excessive Depth Prevent: Positioning, Padding Treatment: Supportive 2. Myopathy Etiologies: Hypotension, Intra-compartmental Pressure, Hypoxemia Prevent: BP, Position, Padding, Treatment: Fluids, Anti-inflammatories, Analgesics

local vs systemic analgesia options for ruminants

* Local Analgesia/anesthesia – Infiltration – Regional – Epidural – IV regional * Systemic Analgesia – Opioids: Butorphanol, Fentanyl, Hydromorphone – NSAIDS