Injectable Anesthetics Flashcards
TIVA
total IV anesthesia
PIVA
partial IV anesthesia; maintained using IV and inhalational agents
Do inhalants have analgesic properties?
no!
Ideal Agents for TIVA
short acting, stable half-life, wide therapeutic window, no active metabolite, and smooth recovery
Most common TIVA for small animals?
propofol-fentanyl CRI
Triple Drip
an anesthetic mix for horses which includes guaifenesin, xylazine, and ketamine
Why can’t ketamine be used alone or repeatedly?
muscle rigidity and stiffness, limits the time it can be used!
Alfaxalone TIVA in cats
less accumulation, can cause dysphoria and twitchiness (myoclonus)
3 Keys of Monitoring Anesthetic Depth
- Will maintain palpebral
- No spontaneous movement
- No nystagmus
Signs anesthesia is too light?
fast palpebral, REM (nystagmus), lacrimation, increased RR, movement
Signs anesthesia is too deep?
absent palpebral, central globe, increased RR BUT shallow breaths, Cheyne-Stokes
Cheyne-Stokes Breathing
atypical pattern of breathing involving deep breathing followed by shallow breathing
Two Options for Opioid CRIs
- Fentanyl (faster onset)
- Morphine (slower onset, longer duration)
Lidocaine CRI
horses and dogs (contraindicated in cats), reduces MAC, MUST BE GIVEN SLOWLY and therapeutic window is narrow
Can ketamine be used for analgesia?
yes, just lower dose; can also combine with opioid
MLK Infusion
morphine, lidocaine, and ketamine
(don’t stop abruptly!)
Can you give MLK to cats?
just skip the lidocaine
Do opioids reduce MAC in horses?
No. But they can still be used for analgesia.
Dexmedetomidine CRI
great sedative and analgesic properties, does have some adverse CV effects (not for at risk patients); small animals and horses
What drugs should NOT be used for TIVA?
barbituates or etomidate
Problems with Etomidate??
adrenocortical suppression (won’t see trauma response) and causes accumulation of propylene glycol!
Reptiles and wildlife - TIVA or PIVA?
TIVA works well for these guys! (esp. alfaxalone)
Context Sensitive Half-Life
elimination half-life CHANGES with duration of infusion (ex: fentanyl and thiopental)
