Ruminant Dr. Bennett

Question 1

Fasting requirements for adult lg ruminants

Answer 1

NPO 12-18 h, no H2O 8-12 h

Question 2

Fasting of sheep & goats

Answer 2

NPO 12-18h, no H2O 4 hours

Question 3

Fasting of calves, lambs, kids

Answer 3

< 1 mo not starved

> 1 mo food withheld 2-4 hours

< 2 mos are considered monogastrics!

Question 4

Common problems with ruminant anes

Answer 4

Regurgitation & aspiration

Ruminal tympany “bloat”

Salivation

Cardio-respiratory effects

Question 5

Regurgitation & aspiration due to

Answer 5

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

Question 6

what is tympany

why occurs

Answer 6

gas produced in rumen is continuous

eructation stops during GA so gas builds

Question 7

Salivation is an issue because…

Answer 7

adult cattle make >50L/day continuously

acid/base effects

Question 8

Cardiorespiratory effects

Answer 8

rumen/viscera press on diaphragm

decr FRC

no eructation

hypoventilation

hypotension - hypertensive can also occur

myopath/neuropathy not an issue compared w/ horses

Question 9

Where to place IVC in ruminants

Answer 9

Jugular v., cephalic v., auricular v.

12-14g catheter in adults

16-18g calves, sheep/goats

Question 10

IF premeds are used what to remember

Answer 10

keep head elevated

maintain sternal recumbency

Question 11

Sedative drugs for ruminants

Answer 11

Phenothiazines

• acepromazine

Alpha2 agonists

• xylazine, detomidine, medetomidine

butyrophenones (more in pigs)

• azaperone

Benzodiazepines

• diazepam, midazolam

Question 12

Acepromazine

Answer 12

sometimes used

may incr risk of regurg

contraindicated in hypovolemic pt

Question 13

Alpha2 agonists

Answer 13

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!

Question 14

Xylazine

Answer 14

Ruminants very sensitive compared to horses - USE 1/10 dose!

Goats more sensitive of all ruminants

Cattle breed differences also

• Herefords & Brahmans more sensitive

Question 15

Detomidine

Answer 15

more potent than xylazine

? decr abortion risk

may use for darting

Question 16

Alpha 2 antagonists (reversal agents)

Answer 16

Atipamezole ($$$) - for dexmedetomadine & medetomadine

Yohimbine - for Xylazine

Tolazoline - for Xylazine (?)

Question 18

Benzodiazepines

Answer 18

mild sedative

typically used in combo w/ ketamine for induction

reversible w/ flumazenil

Midazolam (iv or im)

Diazepam (iv only)

Question 19

Anticholinergics

Answer 19

Atropine

Glycopyrrolate

NOT recommended for routine use

doesn’t decr saliva but makes more viscous

decr GI motility → bloat

Question 20

Analgesia for ruminants

Answer 20

NSAIDs

• carporfen
• meloxicam
• flunixin
• tolfenamic acid
• ketoprofen

Local anesthetics

• procaine/lidocaine
• bupivicaine

Opioids

• butorphanol
• Remember to check FARAD website!*

Question 21

Induction drugs for ruminants

Answer 21

Ketamine

+ GG for adult cattle

+benzo for calves, goat/sheep

Telazol

Propofol

+ ketamine for sm. ruminants

Alfaxalone ?

Question 22

Intubation of ruminants

Answer 22

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

Question 23

Maintenance of anes in ruminants

Answer 23

Isoflurane

Equine circuit for adult cows w/ similar flow & vape settings to horse

Adult human ciruit for calves & sm ruminants

Question 24

As with all lg animals under GA, how to minimize myopathy?

Answer 24

Padding

limbs parallel to ground

lower leg forward to minimize pressure on radial n.

head down allowing drainage from mouth

Question 25

Recovery in ruminants

Answer 25

**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**

Question 26

Camels are similar to which spp? How are they different?

Answer 26

**adult cattle** **ruminoids - 3 compartment stomach** * **adult llamas up to 200kg & alpacas 60kg respectively** **they bite, spit & kick**

Question 27

Problems that can be seen in camelids

Answer 27

**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

Question 28

Challenge to intubate llamas

Answer 28

**have a pharyngeal diverticulum** **phenylephrine gel recommended to aid placement**

Question 29

GA for camelids

Answer 29

**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**

Question 30

Monitoring ruminant anesthesia

Answer 30

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