Anesthesia Of Large Animals, Rodents, And Rabbits

Question 1

Describe anesthetic techniques commonly used in equine practice.

Answer 1

Standing Chemical Restraint - the patient is heavily sedated but remains standing throughout
IM injections are typically not used except with feral horses

Question 2

Explain the special anesthetic challenges resulting from the patient’s temperament, large body size, and equine anatomy and physiology.

Answer 2

“Flight” animals, even if the patient is typically stoic and can behave unpredictably
Anesthetic environment should be calm and quiet with subdued lighting
Specialized equipment such as recovery stalls, hoists, and large animal surgery tables and anesthetic machines
Anatomic concerns involve respiratory, GI, and musculoskeletal systems

Question 3

List the causes of nasal congestion, atelectasis, neuropathy, and myopathy, and describe strategies to prevent these anesthetic complications.

Answer 3

Nasal congestion
- caused by the head being below the withers during general anesthesia
- a nasopharyngeal tube should be placed for recovery

Atelectasis
- caused by pressure being put on the lungs by the GI tract when the horse is placed in dorsal or lateral recumbency
- Ventilation strategies that improve pulmonary gas exchange

Neuropathy
- caused by inappropriate intraoperative padding or leaving the halter on
- provide appropriate padding

Myopathy
- caused by insufficient padding and/or inappropriate positioning of limbs
- making sure muscle groups of supported and do not rest on hard surfaces

Question 4

Describe the differences between anesthetic protocols and procedures used for field anesthesia and anesthesia in a fully equipped equine hospital.

Answer 4

Field anesthesia occurs in a relatively clean stall with short procedures (20-60 mins)
Longer procedures, complex procedures, and procedures involving compromised patients should take place in a hospital

Question 5

Explain the indications for, the advantages of, and risks associated with standing chemical restraint in horses.

Answer 5

Indications:
If the horse’s temperament and surgical approach allow
Advantages:
Helps prevent Neuropathy, myopathy, and atelectasis
Risks:
Hypoventilation, hypoxemia, and hypotension