Avian/Dinosaur Anesthesia Flashcards
T/F birds are viewed as the last surviving dinosaurs
True!
birds have better performing ______ and _______
cardiovascular system
respiratory system
birds don’t tolerate _____ and ____ well
apnea
bradycardia
gas exchange is more/less effected than in mammals
more
what kind of lungs do birds have
flow-through (non-expandable) parabronchial lung system
T/F birds dont have a diaphragm
True
muscles move sternum outward
ventilation and gas exchange are _____
separate
where should intraosseal injections not be given
pneumonatic bones (humerus, femur) - air sacs extend into them
inject in ulna and tibiotarsus
describe the respiratory cycle of a bird
both inspiration and expiration are active
two complete cycles of insp. and exp. needed
is it possible to intubate the abdominal air sacs and ventilate birds with ciontinuous flow?
yes
disadvantage: excessive CO2 removal and anesthetic pollution
T/F birds have countercurrent echange in flow-through ventilation
True
arterial blood and expired gas are not equilibrium
characterisitcs of counter-current flow mechanism
more effective gas exchange
higher ETCO2 than PaCO2
higher PaO2 than PAO2 (negative A-a gradient in birds)
inhalational anesthetic uptake more efficient
what is the dive response
water/diving birds may be affected
stress response
bradycardia and apnea up to 5 minutes
makes inhalant anesthetic induction difficult
may increase mortality
how can dive response be prevented
premedication
putting the whole head into the mask -not just beak
T/F some of the valves of the avian heart are muscular and innervated by Purkinjie fibers
True
extremely quick control, higher performance
what results in quick depolarization of avian heart
purkinje fibers penetrate the myocardium
birds have smaller/larger hearts, lower/higher HR and lower/higher BP and CO than similarly sized mammals
birds have smaller/larger hearts, lower/higher HR and lower/higher BP and CO than similarly sized mammals
T/F bords have a renal portal system that is similar to the hepatic portal system and recieves venous blood from the legs
True
not pbligaory and bypass is possible (controlled process)
why can drugs injected into the hind limbs have decreased potency?
may be metabolized in the kidney through the renal portal system
what are the general recommendations for pre-anesthetic fasting
small birds should not be fasted
8-12 hours for larger species
crop must be empty
sites for SQ injection
area over back, between the wings
wing web, and leg web
inguininal skinfold
intramuscular injection sites
pectoral and thigh muscles
IV injection sites
ulnar
dorsal metatarsal
jugular
in catheter
what are some common premedications
opioid alone (torb or morphine)
opioid + benzodiazepine (good sedatives in many birds)
alpha 2 agonist - larger, aggressive species (caution: CV effects)
there are more/less K opioid receptors in the birds brain than in mammals
more
butorphanol is effective analgesic and often used
why is inhalational induction more common than injectable
difficult to gain IV access
which inhalant anesthetic is preferred
Sevo
put whole head in mask - dive response
which injectable agents can be used for induction
ketamine (with benzos)
propofol (caution: apea)
alfaxalone
which injectable inducation agents can be given IM
ketamine
alfaxalone
T/F intubation may be easy in birds and visibiliy of larynx is normally good
True
T/F if a bird vocalizes during intubation it can indicate traumatic injury to the larynx
False
the syrinx (sound producing organ) is located in tracheobronchial junction and birds may vocalize when intubated
T/F birds have an epiglottis
False
why should you use non-cuffed tubes or not inflated the cuff of ET tube in birds
have complete tracheal rings
can be damaged by inflated ET tube
in birds MAC =
minimum anesthetic concentration
T/F isoflurane MAC values are comparable in avians and mammals
- *True**
1. 3-1.4%
what is the maximum recommended dose of lidocaine
4 mg/kg
what are the perferred routes of fluid administration
intravenous or intraosseous
SQ may be used
T/F depolarization generates apex to base current flow resulting in large negative deflection on ECG (S-wave)
true
bradycardia may occur in response to
drugs (opioids, alpha 2 agonists)
pain
hypothermia
how can bradycardia be treated quickly
give atropine
acheive suffient anesthetic depth/analgesia
warm up
why are pulse oximeters inaccurate in birds
have nucleated RBCs
what is the only accurate method to assess oxygenation
arterial blood gas analysis
birds have a small lung volue therefore apnea may lead to _____
desaturation
monitor ventilation and oxygenation vigilantly and act quickly
T/F overheating may be fatal to birds
True
measure rectal temp regularly
what should be provided at recovery
stress free environment
proper handling
analgesia
warming if needed
antidotes may be considered
incubator in a quite isolated place is ideal
what are some pain behaviors seen in birds
crouching and immobility
failure to dust bath
under or over-grooming of feathers
separation from the flock
T/F NSAIDs can potentially be toxic to birds
True
wide range of avian species → large differences in safe drugs and doses
read up on specific recommendations for each species
