Ruminant Anesthesia Flashcards
what are some considerations with ruminant anesthesia
economic factors (fied vs. hospital; standing vs GA; pet vs production)
welfare considerations (pain management)
drug licensing (withdrawal times, human health)
what are some advantages of a local vs general anesthesia
animals often stoical and well handled
avoid risks of GA
less expensive for farmer and can be performed on farm
what is a posible disadvantage to local vs GA
time frame limited by duration of action of local anesthestic
how long should large ruminants be fasted
NPO 12-18 hours
no water for 8-12 hours
how long should sheep and goats be fasted before anesthesia
NPO 12-18 hours
no water for 4 hours
how long should calves, lambs, and kids be fasted
animals < 1 month of age are not starved
>1month may have food withheld for 2-4 hours
T/F <2 months of age are monogastrics
True
what are some common problems in rumenant anesthesia
regurgitation and aspiration
ruminal tympany
salivation
cardio-respiratory effects
how can you minimize the risk of aspiration
intubate as quickly as possible
use cuffed ET tube
enable drainage from mouth during GA
T/F bloat can occur due to continuous gas production and not being able to eructate during GA
True
how can gas production be reduced
starvation
do not feed highly fermentable foods prior to GA
may place stomach tube and have trochar availablr
do NOT use N2O
what are some management techniques for dealing with salivation
mantain poll above muzzle
infuse LRS during anesthesia
what are some CV effects associated with the rumen/viscera
press on diaphgram
reduction in FRC - increase risk of hypoxemia
absence of eructation - build up of gas, reduction in venous return and hypotension
T/F myopathy/neuropathy is a common problem like in equines
False
not as common as equines
T/F the build up of gas in the rumen can decrease venous return and cause hypotension
true
when vessels are typically used in IVC placement
jugular vein - most common
cephalic, auricular vessels can also be used
what size catheter should be used
adult cattle: 12-14 gauge
calves, sheep, goats: 16-18 gauge
if a premedication is used you should …..
make sure someone stays with the animal
ideally keep head elevated
maintain sternal recumbency
what are two disadvantages to acepromazine
may increase risk of regurgitation
contraindicated in hypovolemic animals
T/F alpha 2 agonists are not recommended in sheep and goats
True
pulmonary effects - bronchconstriction, increased vascular resistance, pulmonary edema
ruminants are more/less sensitive to xylazine than horses
more
use 1/10th the dose, herefords and brahmans more sensitive
which species of rumenants are the most sensitve to xylazine
goats
advantages of detomidine
less risk of abortion
suitible for darting less tractable individuals (can be given IM)
benzodiazepines
mild sedatives
no analgesic effect
few CV and respiratory effects
what reversal agent is used with benzodiazepines
flumazenil
T/F anticholinergics (atropine/gylcopyrrolate) can be used to reduce saliva production
False
makes more viscid - more difficult to manage
common analesics
NSAIDs (carprofen, meloxicam, flunixin)
local anesthetics (procaine/lidocaine, bupivacaine)
Opioids (butorphanol, buprenorphine, morphine)
common induction agents
ketamine
telazol
propofol
alfaxalone
how should large rumanents be intubated
direct palpation
may use stomach tube as a guide for ET tube
high right tracheal bronchus - watch tube length
two techniques for intubating small ruminants
blind - external palpation
direct visualization + laryngoscope
which confirguration should be used for ECG
base - apex
which arteries is most commonly used in direct arterial BP measurement
auricular arteries most common
(sheep lab uses median)
T/F exhaled methane may affect accuracy of capnograph readings
True
how should ruminants be positioned
limbs parallel to ground
pull lower leg forwards and try to minimize pressure on radial nerve in lateral recumbency
head down to allow drainage from mouth
in cases of tympany the animal should be placed in ______ recumbancy
sternal
enable eructation
T/F hypothermia is a consern for small ruminants and calves during recovery
True
what are some specied differences in handling camels and camelids
they can bite, spit and kick
what are some hematological and biochemical differences seen in camels and camelids
higher erythrocyte count
lower mean corpuscular volume
T/F the esophagus in camels and camelids lies to the left of midline
True
aim to the right for venepuncture
T/F llamas are obligate nasal breathers
True
T/F for oral intubation of camels and camelids direct visualization of larynx is required
True
nasal intubation is also possible
when can you extubate camels and camelids
when the animal can withdraw its tongue
what drugs are used for sedation in camel and camelids
alpha 2 agonists - xylazine and medetomidine, +/- torb
diazepam + torb in pediattric animals
induction agents for camels and camelids
guaiphenesin + ketamine
propofol has also been used
