Anesthesiology Exam 2 , Part 2

Front 1

Do ruminants become recumbent when sedated?

Horses?

Back 1

yes

no - they require induction

Front 2

What are signs of sedation in the horse?

*sedation is usually given IV, but IM or oral can be given too

Back 2

head drop, droopy eyes, droopy lips, increased distance between feet, ataxia

Front 3

What is the mechanism of action of acepromazine (a major tranquilizer in horses).

Back 3

inhibits dopamine receptor in the brain (dopamine antagonist)

-peripherally it is an alpha-1 adrenergic block - causes vasodilation

Front 4

Is there a ceiling effect for sedation and side effects with acepromazine?

Back 4

yes for sedation
no for side effects

Front 5

What is the onset time and duration for ace?

Back 5

onset is 20-30 minutes
duration is 5 hours

Front 6

What animals don't you want to use acepromazine on?

Back 6

hypovolemic (care with colics)

Front 7

Why is acepromazine better than alpha-2 for transport?

Back 7

less ataxia

Front 8

Is acepromazine a good sedative in swine?

Back 8

no

Front 9

What is the MoA of alpha-2s?

Back 9

inhibit the release of NE and dopamine in the CNS

Front 10

What 3 things can alpha-2s be used for in the horse?

Back 10

sedation, muscle relaxation, and analgesia

Front 11

Why must you be careful with alpha-2s in horses?

Back 11

-decreased GI motility, diuresis

Front 12

What are 3 side effects of alpha-2s?

Back 12

hypertension, bradycardia, arrhythmia (less severe in horses)

Front 13

Name 3 alpha 2 antagonists?

Back 13

yohimbine, atipemazole, tolazoline

Front 14

How can alpha-2s be administered?

Back 14

bolus or CRI (xylazine, detomidine)

Front 15

What is the most common alpha-2 used in horses?

Back 15

xylazine (IV for horses), (IM for bovine)

Front 16

How can detomidine be given?

Back 16

thru the oral mucosa

Front 17

Which animals are more sensitive to xylazine and what can it cause in the cow?

Back 17

ruminants more sensitive (use 10x lower)

-abortion in cows

Front 18

What can xylazine be used for in horses?

Back 18

to control pain in severe colics - visceral analgesia

Front 19

What happens when you inject xylazine in the carotid artery?

Back 19

immediate collapse

Front 20

What can xylazine cause in sheep?

Back 20

pulmonary edema

Front 21

What is the onset of xylazine in the horse and the duration?

Back 21

3-5 minutes

30-40 minutes

Front 22

What drug can mask surgical colic in the horse?

Back 22

detomidine

Front 23

Which gives better sedation - xylazine or detmidine?

Back 23

detomidine

Front 24

What is the onset of detmonidine in the horse and its duration?

Back 24

onset - 5-7 minutes
duration - 45 minutes

Front 25

Can detomidine be used as a CRI?

Back 25

yes - has a slower kick than xylazine but also can have more severe CV depression

Front 26

What new alpha-2 drug recently introduced into the US market has less head drop than zylazine or detomidine and less ataxia?

Back 26

romifidine

Front 27

How do you give atipemazole, tolazoline, and Yohimbine?

Back 27

IM
-IV administration can cause CV instability

Front 28

What opioid is commonly used in the horse?

What is it esp good for?

Back 28

butorphanol IV

-good for visceral pain and mild ortho cases
-most commonly used for systemic pain releif

Front 29

What is the MoA of butorphanol?

Back 29

k agonist
M antagonist

Front 30

What can butorphanol cause in unsedated and nonpainful horses?

Back 30

excitement

Front 31

Can butorphanol be used as a CRI?

Does it release histamine?

Back 31

yes

no

Front 32

How long must you fast a cow for prolonged recumbency?

short

Back 32

48-72 hours of solids, 24 hours of liquids

-24 hours of solids, 12 hours of water

Front 33

How long must you fast an alpca/ovine, ect?

Back 33

24 hours for food, 12 for water

Front 34

How can chemical restraint for field procedures be achieved in a cow?

Back 34

sedation (alpha -2) and physical restraint

Front 35

How can chemical restraint for field procedures be achieved in a horse?

Back 35

require anesthetic induction

ketamine is most common for field procedures (IV)

-can be used with xylazine
-can be associated with diazepam or GG

Front 36

What is GG and how is it administered?

Back 36

central muscle relaxant only -- not a anesthetic or analgesic (therefore also minimal CV and pulmonary depression)
-IV use ONLY - bolus or CRI

Front 37

What can GG cause if too concentrated?

Back 37

hemolysis

- there is a higher incidence of thrombi formation in the horse

Front 38

What is a triple drip and what is it used for?

Back 38

-ketamine + GG + xylazine

-used as maintenance (limit to 45-60 minutes)

Front 39

What are anesthetic concerns for the bovine?

Back 39

ruminal tympany

respiratory and cardiac
(increased intra-abdominal pressure, decreased diaphragmatic excursions)

(decreased venous return to the heart, impaired CO)

Front 40

How long do you fast a calf?

A neonatal?

Back 40

calf is 12-18 hours, 8-12 water

-neonatal (milk fed) - 2-4 hours -- may need dextrose

Front 41

Where do you give a cow an IV injection?

Back 41

-coccygeal vein
-jugular

Front 42

Which cattle are the most sensitive for sedation and restraint?

Back 42

* Brahamas may be the most sensitive of all the cattle breeds
herfords> holsteins
exotics>domestics

Front 43

What is the reversal drug of choice for cattle?

Back 43

tolazoline

-yohimbine better for horses
-atipemazole is EXPENSIVE

Front 44

Acepromzines provide light sedation in cows - they will still respond to painful stimuli. Where are they contraindicated?

Back 44

-hypovolemic animals
-breeding bulls

Front 45

Name 2 combos you could give a cow for induction/Intubation IV?

Back 45

-ketamine +/- GG (CV stability, but swallow reflex may be hard to abolish)

-thiopental +/- GG (use care in animals with NSAIDs, acidemic animals)

Front 46

What is the technique for bovine intubation?

Back 46

manual technique - palpation

Front 47

Is recovery excitement a problem with cows?

Back 47

rarely - often must be stimulated to rise

Front 48

What are unique challenges with anesthesia and swine physiology?

Back 48

-elongate snout
-mouth does not open wide
-obese
-large, fleshy tongue and soft palate
-hypoplastic trachea/small larynx
-airway with a curve

Front 49

What drugs are not effective for swine?

Back 49

-phenothiazines
-alpha2 if used alone

Front 50

Give some options for swine restraint/sedation?

Back 50

-xylazine + ketamine
-telazol (tiletamine/zolazepam)
-medetomidine + ketamine + butorphanol
-ketamine + midazolam

-usually don't use anticholinergics

Front 51

What are some induction/intubation options for pigs?

Back 51

-thiopental
-ketamine/diazepam
-telazol/xylazine
propofol (expensive)

Front 52

Why can intubation be diffucult with swine?

Back 52

cricoid cartilage and trachea hinders passage of ET
-visualization may be obscured
-prone to laryngospasm
-have a pharygeal recess - blind pouch

Front 53

What is the number one complication with recovery in swine?

Back 53

laryngospasm and airway obstruction post extubation

Front 54

What is the cause of malignant hyperthermia?

Back 54

autosomal dominant gene - breeds with high ratio of muscle to total body mass and grow fast
(Pietrain, Hampshire, Spotten Swine, Landrace, Large White)

Front 55

What type of pre-anesthetic medication is chosen for a cat?

Back 55

neuroleptic combo consisting of a tranqulizer and analgesic

(ace + butorphanol or oxymorphone or hydromorphone or morphine)
-administered IM

Front 56

What drug combo would you use for chemical restraint in a cat?

Back 56

ace + ketamine for chemical restraint
-profuse salivation, min resp depression

-airway reflexes persist, but always a risk of regurg and aspiration

Front 57

When would you use benzodiazepines for pre-anesthetic medications?

Back 57

diazepam - poor IM uptake so use
midazolam - good with opiod

--use when very old, very young or very sick

Front 58

What must you be concerned about with the use of alpha-2s in cats?

Back 58

-decreased CO in a dose dependent fashion - therefore hypoxemic episodes
-increases myocardial sensitization to catecholamines - can potentiate arrhytmias

Front 59

When are alpha-2s contraindicated in cats?

Back 59

-urethral obstruction
-cardiac disease

Front 60

Where do you not want to give thiopental?

Back 60

jugular

Front 61

What induction agents can you use with cats?

Back 61

-thiopental (US acting barbituate) - care with lean animals
-propofol (Alkyl phenol)
-ketamin:diazepam
-Inhalant

Front 62

What can repeated administration of propofol cause in a cat?

Back 62

heinz body formation

Front 63

Ketamine and diazepam is common to use for an INDUCTION agent in cats. Why and in what ratio?

Back 63

good CV stability
-usually in 1:1 ratio

Front 64

What is dose dependant with opioids?

Back 64

excitement

Front 65

What may an excited cat after extubation mean?

What can be given to help with post op laryngeal swelling?

Back 65

hypoxemia - because they are prone to laryngospasm

-dexamethazone

Front 66

When do you induce anesthesia in a horse?

Back 66

only AFTER GOOD SEDATION!

Front 67

What drugs are used for sedatives in a horse?

Back 67

combo of acepromazine, alpha-2 and opioid

Front 68

When is morphine used in a horse?

Back 68

severe pain - usually orthopedic

Front 69

Why is it better to sedate with an alpha-2 prior to the administration of opioids?

Back 69

can cause excitement

Front 70

What are induction drugs to use for a horse?

Back 70

-telazol
-ketamine + (diazepam)/(GG)/(high dose of xylazine sedation)
-thiopental +/- GG
-propofol +/-ketamine - FOALS

Front 71

What is the onset and duration of ketamine in the horse?

Back 71

onset - 2 minutes (this is long in the horse)

duration - 15-30 minutes (donkeys and mules more frequently)

Front 72

Does ketamine increase IOP and ICP?

Back 72

yes

Front 73

What is telazol?

What is the onset and duration of action?

Back 73

combo of tiletamine and zolazepam

-onet is 2 min
-duration is 15-45 minutes

Front 74

What is the MoA of benzodiazepines?

Back 74

GABA agonist

Front 75

Is there a rough or smooth recovery with thiopental?

Back 75

rough

Front 76

Can benzodiazepines cross the placental barrier?

Back 76

Yes and depress the fetus

Front 77

What is the onset and duration of thiopental for horses?

Back 77

onset is 20-30 secondas
duration is 5-15 minutes

Front 78

Is thiopental an anticonvulsant?

Back 78

yes

Front 79

Why may halothane be good or bad for a horse?

Back 79

good - slower recovery because more soluble

bad - sensitize the heart to catecholamine-induced arrhythmias

Front 80

What inhalent is the least metabolized?

Back 80

iso

Front 81

Which inhalent is the least soluble?

Back 81

sevo

Front 82

What can be used as CRIs in a horse?

Back 82

-morphine
-lidocaine
-butorphanol
-xylazine
-ketamine

Front 83

What type of BP do you want in the horse?

Back 83

invasive

Front 84

What is the inotrope of choice for a horse?

Back 84

dobutamine

Front 85

What do you use in horses for nasal decongestion?

Back 85

vasoconstricotrs

Front 86

Does age increase ASA classifications?

Back 86

no - based on presence of systemic disease and severity

-exception is ancient patient

Front 87

What happens to the myocardial fibers with age?

Back 87

atrophy - fibrosis

Front 88

Do older animals have an increased or decreased response to exogenously administered autonomic drugs?

Back 88

decreased (atropine, epinephrine)

Front 89

What does the Mac of inhaled anesthetics do with age?

Back 89

decreases linearly - decreases most anesthetic drugs

Front 90

What do you base drug doses on if >20% of ideal body weight?

Back 90

lean body weight

Front 91

Are alpha-2s the best choice for geriatric patients?

Back 91

no - can cause profound bradycardia

Front 92

When would you avoid giving ketamine?

Back 92

overt cardiac patients
-has sympathomimetic effect on the heart (increases HR)