How to Induce & Maintain Anesthesia Flashcards Preview

Module 14 > How to Induce & Maintain Anesthesia > Flashcards

Flashcards in How to Induce & Maintain Anesthesia Deck (35)
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1
Q

what are routes of admin of anesthesia

A

IM

IV

inhalational

2
Q

when are IM inductions used and what is used

A

ex. feral cat

ketamine based

3
Q

when are inhalation induction agents used

A

some exotics, small mammals

cats, dogs, foals occasionally

4
Q

what are factors affecting the route of administration

A
  1. access to vein
  2. temperament of animal
  3. speed of induction required
5
Q

what factors influence induction

A
  1. speed of injection (too fast, too slow, premedication alters)
  2. hypalbuminemia
6
Q

how do alpha 2 agonists affect the induction speed

A

there might be a slower response to the induction agent

7
Q

how does hypoalbuminemia affect induction

A

less albumin in the blood for the drug to bind to –> propofol is highly protein bound –> less albumin there might need a lower dose than expected

8
Q

what are medications used for co-induction

A

midazolam (beware excitation)

fentanyl

ketamine

9
Q

what are the purposes of co-indcution agents (2)

A
  1. minimize doses
  2. minimize CVS effects
10
Q

how is anesthesia maintained

A

inhalation agents most common

injection (IV)

11
Q

why are IV anesthetics not prefered for maintanence

A

can be expensive and they depress ventilation

12
Q

what can be used to supplement anesthesia and add analgesia

A
  1. fentanyl
  2. ketamine
  3. lidocaine
13
Q

what are the options for airway management (3)

A
  1. mask
  2. supraglottic airway
  3. endotracheal intubation
14
Q

what are the disadvantages of using mask induction

A
  1. risk of leak of gases
  2. difficult to hold in place
  3. doesn’t protect against aspiration
15
Q

when is mask induction helpful

A

very small patients

16
Q

what are laryngeal masks

A

intermediate between mask and ETT

sits over larynx, doesn’t enter trachea

17
Q

how can ET tubes be inserted

A

orally

nasally

18
Q

what are the benefits of ETT

A
  1. allows patent airway (relaxation of tissues)
  2. allows anesthesia to support ventilation
  3. protect against aspiration of material (regurgitation, hemorrhage, saliva)
19
Q

what are the methods of ET intubation

A

blind

manually assisted

laryngoscope guided

bronchoscope guided

20
Q

what are cats prone to when intubating with an ET and how do you prevent it

A

laryngospasm

lidocaine spray

21
Q

how are horses intubated

A
22
Q

how do you tell if the tube is in the trachea (5)

A
  1. visual conformation
  2. condesation in trasparent tubes
  3. breathing system bag movement
  4. palpation of tube
  5. capnography
23
Q

what are the steps following intubation

A
  1. secure tube
  2. inflate the cuff (just enough to stop leak)
24
Q

should you always intubate a dog?

A

easy to intubate ususally

airway may be affected by the anatomy

regurgitation more likely in some dogs

25
Q

should you always intubate a horse?

A

maintain airway well

evidence in cats may increase anesthetic risk

so for short procedures/healthy animals not necessary to intubate

26
Q

should you always intubate a pig/rabbit?

A
27
Q

should you always intubate ruminants?

A

high regurgitation risk

intubation very important if GA

28
Q

how long should the ETT be

A

not past point of the shoulder (can enter 1 bronchus)

29
Q

what are the risks of ETT intubation (8)

A
  1. laryngospasm
  2. trauma/swelling (post op)
  3. endobronchial intubation
  4. kinking ETT
  5. obstruction with secretions (clots of blood)
  6. obstruction of bevelled end
  7. tracheal stenosis (rare)
  8. tracheal rupture (rare)
30
Q

what are 2 good practices before induction

A
  1. place IV line
  2. pre oxygenate (if not stressful)
31
Q

how would you induce and maintain anesthesia in a 2 yo healthy lab for an ovariohysterectomy

acepromazine + methadone IM pre med

A

IV propofol induction

isoflurane maintenance

32
Q

how would you maintain anesthesia in a 7 yo GSD with a ruptured splenic mass

poor pulse, pale

methadone pre med

A

propofol induction in combo with medazolam so we have to use less propofol

33
Q

how would you induce a bulldog for airway surgery

low dose alpha2 + methadone pre med

A

concerned about aspiration, and want quick recovery

definetly pre-oxygenation

induction: rapid in sternal recumbency until tube cuffed, if regurgitates, head down (drain) and have suction ready

34
Q

what is IPPV

A

intermittent positive pressure ventilation

35
Q

why is IPPV needed for anesthesia

A

anesthesia depresses ventilation

or pathophysiology may require ventilation (diaphragmatic rupture)