Sedation and GA of Ruminants Flashcards
Common occult/old bronchopneumonia in ruminants? Consequences of this?
Mycoplasma spp.
Pasteurella spp.
Bordatella spp.
Mannheimia spp.
Parainfluenza
Others
most adult and geriatric small
ruminants that are kept pasturing outside a barn are likely to have had or currently
have some degree of bronchopneumonia that can cause consolidation of lung lobes
as shown in the ventral lobes of this lung, and this can lead to respiratory
complications such as hypoventilation and hypoxemia, which can be fatal.
HR, RR, and rectal temp of cows?
50-80 bpm
12-36 brpm
100.5-102.5
HR, RR, and rectal temp of sheep?
70-80 BMP
12-20 brpm
102-103.5
HR, RR, and rectal temp of goat?
70-90 BPM
15-30 brpm
100.5-103.5
HR, RR, and rectal temp of lamb/kid?
80-150 BPM
20-40 brpm
102-104
Ruminants have 4 chamber stomachs. What is the consequence of this for GA?
- You will want to fast them of food and H2O for at least 12-24 hrs and occasionally 48 hrs in order to reduce fermentation
- Also because their stomach occupy a large part of the chest it reduces their FRC
Why do we avoid excessive fasting in ruminants?
it has been shown to change ruminal flora and potentially cause ketosis and
bradycardia, especially in cattle
Because ruminants cant eructate under GA what are some issues with that?
Methane MUST be vented out because it
cannot diffuse through membranes! SO we have to tube the stomach to vent this out
What are some possible complications of GA in ruminants?
- Regurgitation —> Aspiration of ruminal content
- Bloating aka tympany
- Choking – Upper airway obstruction
Ruminal tympany causes reduced FRC which leads to
Hypoventilation
Hypoxemia
The increase in volume of the rumen causes a cranial shift of the diaphragm leading to those things ^^
Ruminal tympany causes compression of great vessels which leads to
Hypotension
To combat the effects of ruminal typmany these are done:
Less likely if in sternal
recumbency
Right lateral recumbency is
preferred –> this avoids caval compression and regurg
Pass stomach tube to evacuate
gas
How and when does regurgitation occur?
- Not a matter of WHEN & not of IF
- Active (during intubation) –> if too light of plane
- Passive (during GA) –> throughout entire process or intermittent
- In any recumbency
- Dorsal>L Lateral>R Lateral>Sternal
When is regurg the most in terms of recumbency? and the least?
Most: dorsal
Least: sternal
Dorsal>L Lateral>R Lateral>Sternal
What should you avoid to prevent regurg?
Esophageal Intubation
Intubation under light plane of anesthesia
What should you do if regurg is occuring?
Make sure ETT is cuffed properly –> 20-22 mm Hg
Tilt head down –> with towel so oral content can drain out
When is salivation produced? Complications of it?
- Production continues under
sedation/anesthesia
a. 4-6 L/hr adult cattle
b. 0.2-0.6 L/hr SR - Can OBSTRUCT AIRWAY!!!! –> Tilt head down
Do anticholinergic drugs help with salivation?
- Not alot of evidence to support the use of them
- Antisialogogue properties
- May thicken secretions –> favors upper airway obstruction
- Decrease GI motility
What do we need to consider with neonates and juveniles undergoing GA?
- Can be considered monogastric if
still on milk - Limited fasting
–> Non-weaned (1-2 h) – Considered
monogastric due to abomasal
groove
–> Weaned with roughing (6 h) - Risk of hypoglycemia - MONITOR
Whats the main concern of giving drugs to food animals like ruminants?
Considered FOOD, enter food chain –
High concerns about residues
Therefore, there is a legal obligation
to report withdrawal times for milk and meat at discharge.
What must we consider with ruminants when moving them?
SIZE
Ability to move them
Logistics
Facility
Pasture/Stall?
Other things to consider for anesthetic procedures:
- Health status
- Temperament
–> Tame to aggressive - Type of surgery/Medical procedure
–> Invasiveness (imaging procedures vs surgeries)
–> Expected Duration
Health and temperament dictate our sedation
Dairy cows are used to being handled this means what in terms of how we anesthetize them?
Mild physical restraint + local or regional
Beef cattle are infrequently handled how does this affect our anesthetic protocol?
Require more physical restraint
Heavy sedation
Larger doses of sedatives/anesthetics
We performed standing sedation in what bovine?
Dairy cows
Anesthesia for standing sedation
Light sedation
Lower doses of sedatives/anesthetics
What is recommended for GA in bovine (both dairy and beef)?
Endotracheal intubation is recommended due to risk of regurg and upper airway obstruction
Describe recovery of anesthesia in dairy and beef cattle?
Dairy: Recovery usually is smooth
Beef: Recovery can go rough sometimes
depending on animal’s disposition
Why is restraint useful during sedation?
Reduction of stress response
Handling, transportation
Improves operator/patient safety
What are some minor DX procedures and medical procedures?
Minor Diagnostic Procedures
- Radiography, US
Medical Procedures
- Physical examination
- Catheterization
- Wound care
Improves quality of induction of, maintenance of, and recovery from GA
Sheeps and goats are what compared to bovines? Because of this most procedures are done with?
Easier to handle
Most procedures done with:
- Mild physical restraint +
- Light-to-moderate sedation +
- Local anesthesia
For Major procedures theyll require GA and minor procedures we use ^^ that above
When sedating ruminants theyre likely to become:
recumbent (dose and drugdependent)
Sternal
Lateral
Is recumbency always desired?
There are situations in which recumbency is not desirable, such as a C-section in a cow or any other standing procedure we have planned.
What drugs are used fir sedation in ruminants?
Opioids
Benzodiazepines
α2-Agonists (x10 times more
sensitive)
Acepromazine (seldom used)