Field Anesthesia Flashcards
(53 cards)
IV anesthesia is safely used for how long in horses?
Up to 1 hour
What are the contributing factors for mortality from anesthesia in horses?
Age
Duration of surgery
Drugs used for sedation
Inhalants
Preanesthetics must induce:
a state of calmness
What two arrhythmias are common in horses?
AV Block (1st and 2nd)
A-fib
What is an acceptable amount of time to fast a horse before anesthesia?
4-6 hours in general
Some need up to 24-48 hours
What are the three commonly used groups of anesthetics used for standing sedation and premedication?
Alpha2- agonists
Phenothiazines
Opioids
The two most common Alpha-2s used are:
Xylazine, Detomidine
Alpha-2 agonists cause 3 main effects, which are:
Sedation
Muscle relaxation
Analgesia
Peak effect of alpha-2 agonists occurs _____ minutes after IM injection or _____ minutes after IV injection
10-15 minutes; 3-5 minutes
T/F: Xylazine is more potent than Detomidine (Dormosedan)
FALSE
Dorm is more potent
Two of the main side effects of using Alpha-2s for sedation is:
Colic (GI dysmotility)
Increased urination
What are the potential reversal agents for Alpha-2 agonists?
Yohimbine, Atipemazole, Tolazoline
What should you always hold onto for horses sedated with alpha-2s?
The Halter
Oral detomidine takes how long to kick in?
~45 minutes
What is the protocol for delivering a Detomidine CRI for standing sedation procedures >20 minutes (lacerations, laser surgery, thoracoscopy) for a 1,000 lb. horse?
- 3mg Detomidine IV
- 12mg Detmodine in 250mLs NaCL
- Adjust rate up or down as needed throughout procedure
The most common phenothiazine used in horses is:
Acepromazine
What are the characteristics of using Acepromazine as sedation in horses? (4)
- Onset 15-30 minutes
- Duration 6-10 hours
- Minimal muscle relaxation & ataxia
- No analgesia
What are the potential side effects of using acepromazine?
-Priaprism (caution in breeding stallions)
-Hypotension
Which sedative class is more effective when used in conjunction with dissociatives?
Alpha-2 agonists
What are the 3 main opioids used in equine sedation protocols?
Butorphanol
Morphine
Transdermal Fentanyl
Why do we give opioids in addition to tranquilizers?
Opioids can cause excitement when given alone
What are the common drugs/classes used for induction and total IV anesthesia (TIVA)?
Dissociatives (Ketamine, Telazol)
Benzodiazepines (Midazolam, Diazepam)
Propofol
Which drug class causes muscle relaxation during induction and TIVA?
Benzodiazapines
Use of dissociatives results in a smoother induction and recovery when used in conjunction with:
Alpha-2 Agonists