anesthesia and sedation Flashcards
IV anesthesia is safely used for up to?
1 hour
what are high risk factors for mortality during anesthesia
really young, really old, long surgeries
what is the main thing to remember about anesthetizing a horse
never anesth an excited horse. give more sedative (xyla)
most common arrhythmias
1st and 2nd degree AV block
general patient prep before anesthesia
fast for 4-6 hours. rinse mouth out, ask about tying up history bc they usually need more sedation
what are the A2s, and what do they do
xylazine and detomidine
sedation, muscle relaxation, analgesia
goal HR during anesth
> 20BPM
why dont we reverse a2s
they jump up too fast, and its best to let it get up slowly
what does the phenothiazines do (ace)
tranquilizes but does not sedate. NO analgesia, no ataxia
what is the thing to remember about giving ace to a male horse
priaprism has been seen
what is the best sedation combo
xyla + ketamine
or xyla + ace
what effects do opioids have
alone- excitement
adjunct to A2s help with sedation and analgesia
what are the three things we use for total IV anesthesia (TIVA)
ketamine/telazol
muscle relaxants
propofol
route of ketamine
IV only
what to remember about xyla + ketamine
apneustic breathing common, poor muscle relaxation, minor surgeries only
what to remember about TKD
recumbency in 1 minute
should not be used alone for surgery
what is our muscle relaxant
GG, does NOT do unconsciousness or analgesia
Benzos
why do we use GG in anesth
allows you to use less of the other drugs
what are the signs of GG overdose and about how much is getting close to an overdose
~3L
they start looking light, stiff, labored breathing, deep breaths
why do we not use Propofol in the field often
it causes respiratory depression which can be tricky in the field
what do we do to maintain anesthesia
give 1/3 to 1/2 of the X/K dose to effect, or add GG/K
when can we use triple drip and what to remember
induction in foals, maintain anesthesia for 1 hour
need a large catheter, supplement O2
what do we monitor in short procedures
digital pulse, CRT, observe RR
what is a major sign the horse is getting light
increased RR or deep forceful breaths
all recumbent horses are
hypoxic
most injuries are during
recovery/induction
what is the most common choice for a local block
2% lidocaine. lasts 1-2 hr
when should we give the intratesticular lidocaine in castrations
after the first scrub so there is time for it to work.
what is the most important motor block for the eye
facial n auriculopalpebral branch – palpebral branch. 1-2ml
what block is sensory to the upper eyelid
supraorbital n. branch of the trigeminal n
blocking the rostral infraorbital n blocks what
upper lip and nose
caudal infraorbital II blocks what
teeth to the 1st molar, sinus, skin to medial canthus
what does the maxillary block
all upper teeth and nasal cavity
what does mental I (rostral) block
lower lip
what does mental II (caudal) block
lower incisors
when do we give an epidural and what type
rectal, vaginal, perianal, urethra and bladder procedures
caudal epi is most common because a LS can drop a horse
what to remember about caudal epidural
same as cattle. 18g 1.5in needle. move tail to locate the correct space, easy, large volume could impair motor to hind limbs
when would we use an epidural catheter
frequent dosing for fractures- pelvic, hindlimb-, septic joints
what catheter do we use for caudal epidural
17g huber point directional needle with stylet
what can we put in an epidural
A2, opioids, ketamine, lidocaine
if you give an alpha 2 in an epidural what do you need to remember
it will act systemically
how does an opioid epidural differ from other drugs
it causes analgesia with no risk of motor blockade. – fracture comfort, mild systemic effects seen.
should you use ketamine alone in an epidural
it provides poor visceral analgesia so combine it with lidocaine
side effect of morphine specifically
local pruritis at the area of analgesia
