Lecture 11 Swine Anesthesia Flashcards

1
Q

How long do pigs need to be fasted

A

Pigs fasted 24 hours before surgery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Reasons to anesthetize pigs

A
  • Farm animals
    • Castration, hernia
  • Pets
    • Variety of conditions
  • Biomedical Research
    • Experimental surgery
    • Organ transplant
    • Bypass surgery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Problems with Pig Anesthesia

A
  1. Wide range of sizes
  2. Manual restraint is difficult
  3. Physical exam often impossible
    • History important for physical status
  4. IM injection
    • drugs deposited into fat
  5. Limited IV access options
  6. Endotracheal intubation
  7. Malignant hyperthermia
  8. Extra label drug use
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q
  1. Do pigs have small or large hearts relative to body mass
  2. rapid or slower heart rates
  3. Does tachycardia reduce cardiac output?
A
  1. Small heart relative to body mass
  2. Rapid heart rate
  3. Tachycardia markedly reduces cardiac output
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q
  1. Do pigs have a low or high incidence of rhinitis
  2. low or high incidence of pneumonia and pleuritis?
  3. Upper airway easily or not obstructed?
  4. Lots or little airway secretions
A
  1. High incidence of rhinitis
  2. High incidence of pneumonia, pleuritis
  3. Upper airway easily obstructed
  4. Airway secretions easily obstruct airway
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q
  1. IM injections for comercial pigs
  2. Pet pigs
  3. Short or long needles?
A
  1. Commercial pigs
    • close to the ear base
  2. Pet pigs
    • thighs, epaxial muscle
  3. Use long needle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

IV access sites

A
  • auricular vein (dorsal surface of ear)
  • Limb veins OK once asleep
  • Use elastic band to help raise the vein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the different sedatives and anesthetic agents used in pigs

A
  1. Butyrophenones
    • Azaperone
  2. Acepromazine
  3. a2 agonists
    • Xylazine, dexmedetomidine
  4. Opioids
    • Hydromorphone, butorphanol
  5. Midazolam
    • IM or intranasal
  6. Dissociative agents
    • Ketamine, Telazol
  7. Propofol ($)
  8. Anticholinergics
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is special about mode of administration of midazolam in pigs

A

IM or intranasal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q
  1. What type of drug is Azaperone
  2. Side effects are similar to what other drugs
  3. What can it be used for?
A
  1. Butyrophenone
  2. Similar effects and side-effects to acepromazine
  3. Uses:
    • Short acting tranquillizer used by pig farmers
    • Can be useful as premed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q
  1. Azaperone can be given through what mode?
  2. What is another butyrophenone
A
  1. IM only
    • Excitement IV
  2. Droperidol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q
  1. What are the alpha-2 agonists used in pigs?
  2. Alpha-2 Agonists are mixed with what drugs with pigs?
A
  1. Xylazine and Dexmedetomidine
  2. In combination with ketamine- very effective.
    • Limited effect if used alone
      • Need higher doses e.g. 2 mg/kg
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How can you do injectable anesthesia in pigs? (what drugs)

A
  • For induction and maintenance
    • Xylazine-Telazol-Ketamine (TKX) IM
  • Additional drugs IV if needed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How do you do inhalational general anesthesia in pigs

A
  • •Isoflurane or $evoflurane
  • •Face mask
    • –To induce anesthesia in piglets
    • –To complete induction after heavy IM sedation
  • •ET tube for anesth. maintenance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are considerations of Endotracheal Intubation with pigs

A
  • Jaws don’t open widely
  • Soft palate is long
  • Larynx and trachea set at an angle
  • Prone to laryngospasm
  • Narrow trachea
  • Tracheal bronchus can be occluded by ET tube
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Endotracheal Intubation Equipment

A
  1. Face mask for preoxygenation
  2. Bandage to hold open mouth
  3. Choice of ET tubes
  4. Lidocaine (spray on larynx)
  5. Laryngoscope
  6. Stylet
17
Q

If impossible to visualize larynx what other method can you use to administer oxygen/ inhalent anesthesia

A
  • Bilateral nasal tubes
    • 6-8 mm ID
    • Inflate cuff inside nasal cavities
    • Carlen adapter to connect to breathing system
18
Q

At what weight do you switch to using the large animal anesthesia machine for pigs?

A
  • If ET tube 16 mm
  • If body weight > approx. 200 kg
19
Q
  1. What should the HR be for pigs under anesthesia?
  2. BP?
A
  1. HR 60-90 bpm
  2. Blood pressure
    • syst. > 90 mmHg or
    • mean > 60 mmHg
20
Q

What are methods to measure BP in pigs

A
  1. Non invasive - oscillometer or Doppler
    • Limbs taper (cone shape) and cuffs don’t fit well
  2. Invasive - auricular artery
21
Q
  1. What temperature do pigs generally run in under anesthesia (cold or hot)
  2. Why?
A
  1. Hyperthermia
  2. Small body surface area relative to body mass
22
Q

How do you test depth of anesthesia

A
  1. Jaw tone is helpful
    • Absent for surgical level of anesthesia
  2. Pedal reflex
    • Can squeeze a toe with a hemostat in small swine
  3. Eyes are of limited value
    • Sunken and palpebral reflex hard to evaluate
23
Q

How do you recover a pig

A
  1. Extubate trachea when swallowing reflex
  2. Help to sternal recumbency
  3. Usually smooth process
    • No need for further sedation
24
Q
  1. What causes Malignant Hyperthermia
  2. What breeds commonly get it?
A
  1. Inherited genetic disorder
    • Ryanodine receptor on sarcoplasmic reticulum leads to lots of Ca++ release
  2. Breeds:
    • Duroc
    • Landrace
    • Pietrain
25
Q

What can cause malignant hyperthermia

A
  • Stress, transport, drugs
  • Anesth. gases, suxamethonium
26
Q

What signs do you see with malignant hyperthermia

A
  1. Tachycardia
  2. Hypercapnia
  3. Muscle rigidity
  4. Hyperthermia (109 °F)
27
Q

Treatment of Malignant Hyperthermia

A
  1. Discontinue the trigger agent – e.g. isoflurane
    • Change anesthetic machine
  2. Dantrolene – intracellular muscle relaxant
  3. Cool the body – ice and cool IV fluids
  4. Oxygen
  5. Supportive therapy
  6. Human - http://www.mhaus.org/
    • Let us know if this exists in your ancestry
28
Q

What are important things to know about Analgesia in Food Animals

A
  • All animals feel pain
  • Assessment may be challenging
    • Prey species/behavioral differences
    • Response to drugs (e.g. opioids)
  • Some signs
    • Dull appearance, grinding of teeth
    • Refusal of food, no rumination
    • Abnormal posture, vocalization
  • Multi-modal approach when possible
    • At least local anesthetics & NSAIDs
  • ELDU - check Farad