Lec 17 & 18 - SA Drug Selection pt 1 & 2

Dr. Johnson - Exam 2

What are the 4 goals of small animal anesthesia?

1. unconsciousness

2. loss of movement

3. loss of nociception

4. homeostasis

Signalment consists of what 3 things?

age, breed, sex

Why is anesthetizing very young (<11 wk) and old (>80% life expectancy) patients different from middle aged, healthy patients?

they will have delayed metabolism of drugs

What are the 4 vital signs assessed during a physical exam?

1. temp

2. pulse

3. respiratory rate

4. pain

Which pre-anesthetic diagnostic tests have been shown to reduce anesthetic mortality in otherwise healthy patients?

NONE → common tests = PCV/TS, glucose, CBC/Chem, UA, blood gas, bile acids

Which lab/diagnostic findings are direct indicators of hepatic function which may indicate delayed drug metabolism?

bile acids

Describe ASA I classification and give some examples.

elective procedure on a healthy patient → spay, neuter, dental

Explain ASA II classification and give some examples.

necessary procedure on systemically healthy pt or one with mild systemic disease → TPLO, fx repair, mass removal

Explain ASA III classification and what conditions might fall under this classification.

severe but stable systemic disease → stable renal failure, CHF, controlled DM

Explain ASA IV classification and what conditions might fall under this classification.

systemically decompensated, constant threat to life → GDV, hemoabdomen, septic

Explain ASA V classification and what conditions might fall under this classification.

moribund, life expectancy <24 hr → septic shock, perforated bowel

usually just a human med issue

What are 3 advantages for incorporating NSAIDs into an anesthetic plan?

1. long acting

2. central and peripheral effects

3. no reaction with anesthetics

What are 2 disadvantages of including NSAIDs in an anesthetic plan?

1. inadequate for surgical pain

2. interferes with normal homeostatic prostaglandins

What are 3 advantages of using a sedative as a premedication?

1. agent reduction

2. facilitate handling

3. analgesia

What are 3 sedatives/anxiolytics that can be used as a premedication and their drug class?

1. acepromazine → phenothiazine, dopamine, & alpha-2 agonist

2. dexmedetomidine → alpha-2 agonist

3. midazolam → benzodiazepine, GABA agonist

What are 2 advantages of using an opioid as a premedication?

1. synergism for sedation

2. analgesia

What are 4 opioids that can be used as a premedication?

1. butorphanol → Kappa agonist

2. hydromorphone → Mu agonist

3. morphine → Mu agonist

4. buprenorphine → partial Mu agonist

What are 4 reasons why inhalant inductions are not recommended?

1. increased mortality

2. no airway control

3. cardiovascular depression

4. stress

What effect does propofol have on the respiratory system?

transient apnea

In cats, what side effect is caused by repeated exposure to propofol?

Heinz body anemia

What is the most common cardiovascular side effect seen when inducing with a dissociative such as ketamine?

myocardial depressant

Of the injectable induction agents, which has the longest duration of action?

dissociatives/benzodiazepines (ketamine, telazol)

Of the injectable induction agents, which has the least cardiovascular effects?

etomidate

What is the most common side effect seen during induction with etomidate?

maintained gag reflex

Which of the induction agents has demonstrated superior puppy vigor after C-section?

alfaxalone

What are the 3 advantages to using local/regional anesthesia?

1. blocks pain pathway low

2. eliminates surgical stimulation

3. reduces system analgesics = less side effects

What is a simple block that can be performed for a canine castration?

testicular block

What are 3 indications for the use of a mandibular nerve block?

1. extractions

2. fracture

3. -ectomy

What is an appropriate regional anesthesia technique for repair of a radius/ulna fracture?

brachial plexus block

What are the 3 most common disadvantages for use of epidural anesthesia/analgesia?

1. motor blockade (local anesthetics)

2. sympathetic blockade (local anesthetics) → hypotension

3. failure → risk of infection, pruritis (morphine), urine retention

What pharmacologic property makes morphine the most suitable opioid for use in the epidural space?

poorly lipophilic = longer duration due decreased absorption (sits in epidural space)

Which class of opioids can be used as a CRI?

Mu agonists → morphine, methadone, hydromorphone, fentanyl, remifentanil

Which class of drugs is most effective in managing post-operative inflammatory pain?

NSAIDs