1.3 Rabbit, Rodent, and Ferret Anesthesia

Question 1

What are pre-anesthetic considerations of small mammals?

Answer 1

always stabilize first, even if apparently healthy!

• O2
• warmth
• fluids
• nutritional support
• analgesia
• gut stimulants (?)

(5) Try to wait 24-48 hours and stabilize a patient completely before going to anesthesia, even if they are not acutely sick. Obviously this cannot be done for an emergency surgery.

(4) These all are in consideration of the 5 stabilization steps -> go back to Small Mammal GI Stasis to review.

(2) Can also give some medazolam to calm.

(3) Pre-anesthetic fasting is not necessary for the rabbit or rodent.

Question 2

What is the best way to induce small mammals?

Answer 2

IM/SC induction is the best option if possible

• alpha-2 + ketamine +/- opioid most common
• be wary of this combo in sick animals due to its resp/CVS effects: lower dose and combine with others

IV induction is a good method if given slowly, BUT requires venous access, can cause severe respiratory depression, and requires very fast intubation

• do not use if uncomfortable intubating small mammals

gasseous induction: we have almost completely moved away from gassing down rabbits, and have instead transitioned to injectables

• sometimes, gassing down is appropriate for rodents
• sevoflurane less irritant than isoflurane
• good for hepatic/renal imparement

Question 3

What is true about intubating small mammals during GA?

Answer 3

advised for every rabbit and ferret, but not always possible in rodents

• preoxygenate first always
• do not attemt more than 3 times (laryngeal damage)
• laryngeal mask or nasal intubation possible but have drawbacks (LM easy to place but easy to displace: good for emergency)
• rodent intubation posssible with endoscope but almost never done

Question 4

What is specifc to small mammals and maintenance/monitoring?

Answer 4

due to small size, fast metabolism, and low circulating volume you MUST notice monitoring changes IMMEDIATELY and respond quickly; changes occur rapidly:

1. small mammals have very little oxygen reserve
2. hypothermia common (and avoidable)
3. post anesthetic ileus risk high for small mammals: reduce via gut stimulants and adequate analgesia (opioids and NSAIDs); if not eating wihtin a few hours post-op, syringe feed routinely

have eyes on the patient AT ALL TIMES