Ruminant Dr. Bennett Flashcards
Fasting requirements for adult lg ruminants
NPO 12-18 h, no H2O 8-12 h
Fasting of sheep & goats
NPO 12-18h, no H2O 4 hours
Fasting of calves, lambs, kids
< 1 mo not starved
> 1 mo food withheld 2-4 hours
< 2 mos are considered monogastrics!
Common problems with ruminant anes
Regurgitation & aspiration
Ruminal tympany “bloat”
Salivation
Cardio-respiratory effects
Regurgitation & aspiration due to
rumen cannot be emptied of food
induction causes relaxation of GI sphincters/change in intra abd pressure
to minimize:
intubate ASAP
use cuffed ETT
enable drainage from mouth
what is tympany
why occurs
gas produced in rumen is continuous
eructation stops during GA so gas builds
Salivation is an issue because…
adult cattle make >50L/day continuously
acid/base effects
Cardiorespiratory effects
rumen/viscera press on diaphragm
decr FRC
no eructation
hypoventilation
hypotension - hypertensive can also occur
myopath/neuropathy not an issue compared w/ horses
Where to place IVC in ruminants
Jugular v., cephalic v., auricular v.
12-14g catheter in adults
16-18g calves, sheep/goats
IF premeds are used what to remember
keep head elevated
maintain sternal recumbency
Sedative drugs for ruminants
Phenothiazines
- acepromazine
Alpha2 agonists
- xylazine, detomidine, medetomidine
butyrophenones (more in pigs)
- azaperone
Benzodiazepines
- diazepam, midazolam
Acepromazine
sometimes used
may incr risk of regurg
contraindicated in hypovolemic pt
Alpha2 agonists
Potent sedative & analgesic
- hypertension, bradycardia
- decr GI motility
- anti insulin effect & hyperglycemia
- osmotic diuresis & inhibition of vaspression secretion
- incr risk of abortion (XYLAZINE)
- NOT recommended in sheep/goats due to pulmonary effects!
Xylazine
Ruminants very sensitive compared to horses - USE 1/10 dose!
Goats more sensitive of all ruminants
Cattle breed differences also
- Herefords & Brahmans more sensitive
Detomidine
more potent than xylazine
? decr abortion risk
may use for darting
Alpha 2 antagonists (reversal agents)
Atipamezole ($$$) - for dexmedetomadine & medetomadine
Yohimbine - for Xylazine
Tolazoline - for Xylazine (?)
Benzodiazepines
mild sedative
typically used in combo w/ ketamine for induction
reversible w/ flumazenil
Midazolam (iv or im)
Diazepam (iv only)
Anticholinergics
Atropine
Glycopyrrolate
NOT recommended for routine use
doesn’t decr saliva but makes more viscous
decr GI motility → bloat
Analgesia for ruminants
NSAIDs
- carporfen
- meloxicam
- flunixin
- tolfenamic acid
- ketoprofen
Local anesthetics
- procaine/lidocaine
- bupivicaine
Opioids
- butorphanol
- Remember to check FARAD website!*
Induction drugs for ruminants
Ketamine
+ GG for adult cattle
+benzo for calves, goat/sheep
Telazol
Propofol
+ ketamine for sm. ruminants
Alfaxalone ?
Intubation of ruminants
Cattle by direct palpation
- watch high R bronchus
ETT 20-30 mm ID, adults
8-12 mm ID, calves
Sm ruminants blind or laryrngoscope
- use stylet & topical local anes
ETT 7-12 mm ID, adults
Maintenance of anes in ruminants
Isoflurane
Equine circuit for adult cows w/ similar flow & vape settings to horse
Adult human ciruit for calves & sm ruminants
As with all lg animals under GA, how to minimize myopathy?
Padding
limbs parallel to ground
lower leg forward to minimize pressure on radial n.
head down allowing drainage from mouth
Recovery in ruminants
calmer than horses
risk of regurg & aspiration
- leave ETT in place as long as possible
- remove w/ cuff inflated
tympany - support in sternal
enables eructation
hypothermia in sm. ruminants/ calves
ck temp & use heating support
Camels are similar to which spp?
How are they different?
adult cattle
ruminoids - 3 compartment stomach
- adult llamas up to 200kg & alpacas 60kg respectively
they bite, spit & kick
Problems that can be seen in camelids
bloat
regurgitation
aspiration
venipuncture
- more challenging:
skin very thick, especially in adult males
no jugular groove
muscle over lies the vein in some locations
esophagus lies to the left of the midline
valves are present within the jugular vein
Challenge to intubate llamas
have a pharyngeal diverticulum
phenylephrine gel recommended to aid placement
GA for camelids
Sedation
Alpha2-adrenoceptor agonists can be used
xylazine but medetomidine has also been used in llamas
±butorphanol
diazepam + butorphanol in pediatric animals
Induction of anesthesia
guaiphenesin + ketamine for induction of anesthesia
propofol has also been used in llamas
Maintenance of anesthesia
isoflurane and previously halothane
Monitoring
as for other species
take special care of the eyes since they are large and prominent
Monitoring ruminant anesthesia
ECG
may use base-apex lead configuration
direct arterial BP measurement
use auricular arteries most commonly
pulse oximetry
may be less accurate if tongue is pigmented
arterial blood gas analysis
respiratory gas monitoring
remember they exhale methane –this may affect the accuracy of your capnography readings
Use IPPV if hypoventilation occurs
body temperature
