Lecture 2.2 10/14/24

Question 1

What are the options for delivering oxygen to a patient?

Answer 1

-flow-by
-mask
-oxygen chamber
-nasal cannula
-endotracheal tube

Question 2

What are the characteristics of the receptors involved in coughing?

Answer 2

-stretch and C fibers
-mechanoreceptors and chemoreceptors
-numerous in larynx and airways
-respond to bronchoconstriction and bronchospasm

Question 3

What is the cough reflex arc?

Answer 3

-stimulus in airway sends signal to brain via vagal airway sensory nerve
-brain sends signal via respiratory motor nerve to the respiratory muscles to initiate coughing

Question 4

What are the characteristics of narcotics for antitussive therapy?

Answer 4

-central binding
-bind opioid receptors in cough center and depress sensitivity to afferent stimuli
-controlled substances; makes at home therapy more difficult

Question 5

What are the characteristics of hydrocodone?

Answer 5

-contains homatropine, which exerts significant effects such as vomiting
-homatropine is meant to prevent abuse but also limits dosing

Question 6

What are the characteristics of dextromethorphan?

Answer 6

-not a true opiate since it does not bind to mu or kappa receptors
-ineffective in dogs as an antitussive

Question 7

What are the characteristics of maropitant/cerenia?

Answer 7

-NK1 receptor antagonist
-may be an antitussive useful for chronic cough

Question 8

What are the bronchodilator classes and the species they are used in?

Answer 8

-anticholinergics: horses
-beta-receptor agonists: small animal and horses
-methylxanthines: small animal

Question 9

Why is atropine not used as an antitussive?

Answer 9

too many side effects

Question 10

What are the characteristics of ipratropium bromide/atrovet?

Answer 10

-aerosol quaternary amine
-topical form of atropine

Question 11

Why should an antitussive therapy NOT activate alpha receptors in the sympathetic response?

Answer 11

-increases cGMP
-increases mucus production
-increases bronchiolar constriction

Question 12

Why should an antitussive therapy activate beta receptors in the sympathetic response?

Answer 12

-increases cAMP
-causes bronchodilation
-decreases mucus production

Question 13

What is the mechanism of action for adrenergic agents?

Answer 13

-stimulate beta receptors to ultimately increase cAMP and cause bronchodilation
-stabilize mast cells to decrease inflammatory response
-beta2 receptors are selective for bronchodilation, so direct cardiac effects are unlikely

Question 14

What are the characteristics of terbutaline sulfate?

Answer 14

-selective beta2 adrenergic agonist
-used in dogs, cats, and horses
-administered SQ, IM, IV, PO, or elixir

Question 15

What are the characteristics of clenbuterol sulfate?

Answer 15

-selective beta2 adrenergic agonist
-used in horses
-administered PO

Question 16

What are the characteristics of albuterol sulfate?

Answer 16

-selective beta2 adrenergic agonist
-used in horses
-emergency drug in dogs and cats
-administered parenteral, oral, or inhalation

Question 17

What are the methylxanthine drugs?

Answer 17

-caffeine
-theobromine
-aminophylline/theophylline

Question 18

What is the mechanism of action for methylxanthines?

Answer 18

-inhibit PDE related breakdown of cAMP
-increased cAMP leads to greater relaxation
-antagonizes adenosine receptors that stimulate contraction
-less potent than beta2 agonists
-cause bronchodilation with risk of CNS and cardiac stimulation

Question 19

How does aminophylline differ from theophylline?

Answer 19

-aminophylline contains ethylenediamine and water molecules
-aminophylline can be injected while theophylline can only be administered orally

Question 20

Why is it important that aminophylline and theophylline have a low therapeutic index?

Answer 20

-there are lots of side effects
-dose adjustment is needed during drug monitoring

Question 21

What are the glucocorticoids used in antitussive therapy?

Answer 21

-prednisone
-prednisolone
-dexamethasone

Question 22

Why is the NSAID flunixin not commonly used in small animal antitussive therapy?

Answer 22

damaging to the kidneys

Question 23

What is the mechanism of action of glucocorticoids?

Answer 23

-interacts with DNA
-suppresses multiple inflammatory genes that are typically activated in asthmatic airway
-stimulates production of lipocortin, which decreases prostaglandin production by suppressing phospholipase A

Question 24

What are the outcomes of glucocorticoid therapy?

Answer 24

-decreased airway inflammation
-increased sensitivity and receptor density of beta2 receptors
-potential side effects including PU/PD and appetite changes

Question 25

How are glucocorticoids administered?

Answer 25

-oral
-inhaled nebulization/aerosol

Question 26

What are the characteristics of fluticasone?

Answer 26

-glucocorticoid
-local action
-less side effects
-used for asthma maintenance

Question 27

What are the characteristics of NSAID use for antitussive therapy?

Answer 27

-inhibits cyclooxygenase to decrease prostaglandin production
-used in large animal for some lung diseases
-rarely used in small animal