Anesthesia and Analgesia of Small Mammals

What 7 things are a part of a pre-anesthetic evaluation?

History, wild vs. pet, healthy vs. sick, physical exam, be familiar with the ailments of each species, body weight, and blood work

Why is fasting required for ferrets and how long should you fast for? How long should you withhold water?

Ferrets will vomit, fast for 4-6 hours, no water for 2 hours

Why don’t rabbits require fasting? What should you still withhold from them despite this and why? How long should you withhold water and food?

They will not vomit. Still withhold grain/pellets, it may create bloat. Water is 0-6 hours and food is 0-24 hours

What should you check on a guinea pig before anesthesia and why? How long should you fast them for? How long should you withhold water?

Cheek pouches for food so they don’t aspirate it. They may regurgitate, fast 6-8 hours, no water for 2 hours

How long should you fast rodents and why?

1 to 4 hours, they have a fast metabolism

What is the most important part of pre-anesthetic preparation in small mammals?

Reduce stress

How do you reduce stress on a small mammal?

Warm, dark, quiet place for up to a few hours before procedure, and allow time to accommodate to unfamiliar surroundings

What should you always do before anesthesia?

Stabilize systemic status. Mainly temperature, hydration, and blood glucose

What is the blood volume of small mammals?

50-80mL depending on species

What 4 reflexes do you check to check the level of anesthesia?

Pedal withdrawal reflex, auricular reflex (rabbits), palpebral reflex and corneal reflex

What is the goal of checking cardiopulmonary function during anesthesia?

To note and prevent hypotension, bradycardia, hypoxemia, and hypercapnia

What monitoring tool should you not use and why?

Alligator ECG clamps, can case pressure necrosis or burns

What is the normal heart rate for a rabbit? For mice?

Rabbit: Up to 350bpm, mice: Up to 600bpm

What are 3 of the most important things to remember during maintenance of anesthesia?

Protect the eyes (eye drops or lube) and maintain body temperature

What drug us best to use for pain management and why?

Buprenorphine, longer acting opioid q. 6-12 hours

What are 8 complications of anesthesia?

Hypothermia, anesthetic overdose, cardiovascular collapse, respiratory depression, laryngeal trauma, airway obstruction, preanesthetic excitement, and hypoglycemia

True or False: There is a routine protocol for small mammals.

False

Why should you avoid multiple intubation attempts?

Can cause laryngeal edema

What NSAID is most commonly use in small mammals?

Meloxicam

True or False: You should use a multimodal analgesia technique in small mammals

True

What can a rabbit fracture if it gets stressed and kicks violently?

Its lumbar spine

Rabbits have a preexisting lung disease - upper respiratory infection (pneumonia). What is another name for this?

Occult pasteurellosis infection

What parasite can affect renal function in rabbits?

Encephalitozoon cuniculi

What happens if a rabbit gets bloated?

Their bloated abdomen will compress the diaphragm and it is hard for them to breathe and ventilate during anesthesia

When giving atropine to fix a rabbits bradycardia, what should you do to the dose and why?

Use a higher dose, rabbits produce an enzyme called endogenous atropine esterases which breaks down atropine

What other drug besides atropine can you use to fix bradycardia?

Glycopyrrolate

Where can you palpate pulses or measure blood pressure in rabbits?

Central auricular artery

True or false: you can place a blood pressure cuff on the base of a rabbits ear

True

Where should the head be positioned for intubation?

Head and neck should be straight up in a full extension

What are 3 characteristics to remember when intubating a rabbit?

They have a long soft palate, large epiglottis, and a larynx that is smaller than their trachea

What are 2 ways to intubate a rabbit?

Orally and nasally

What is the most important thing to do in guinea pigs and chinchillas?

Active monitoring of airway patency

What do guinea pigs and chinchillas produce copious amounts of and what will it cause?

Bronchial secretion, cause obstruction in a small diameter ET tube

Where are the 2 areas to place an IV catheter in guinea pigs and chinchillas?

Cephalic vein or intraosseous

In guinea pigs, the fusion of the soft palate to the base of the tongue is called what?

Palatal ostium

What should you do especially if you intubate (for guinea pigs and chinchillas)?

Monitor for signs of upper airway obstruction

What can prolonged fasting and ongoing diseases cause in ferrets?

Hypoglycemia

What can a ferrets small size cause?

Hypothermia

What 3 places can you place an IV catheter in ferrets?

Cephalic, saphenous, or jugular

What should you apply to a ferrets arytenoids for intubation and why?

Lidocaine to decrease laryngospasm

What are 2 analgesia drugs used in ferrets?

Butorphanol or buprenorphine

What is common in ferrets?

Hypotension

Why should you make sure to do IM injections in hedgehogs?

They have a lot of subcutaneous fat (50% of their body weight) that will delay absorption

What route should you give injections in rodents and what should you do to the drug volume?

IM injections, larger volumes