Respiratory Flashcards
What would be the best way to stop continuous sneezing in a dog?
Intranasal application of a topical anesthetic (Lidocaine)
Why do bronchodilators sometimes decrease coughing?
Mucosal irritation does not directly stimulate the cough reflex, but causes bronchoconstriction which serves as the primary stimulus to cough
Bronchodilators will then dilate the bronchi which will decrease the coughing
What is/are the limitation(s) in using dextromethorphan or antihistamines as cough suppressants in dogs?
They have a short half-life and limited bioavailability
How much evidence supports the use of hydrocodone as an antitussive?
Very effect cough suppressant
How much evidence supports the use of butorphanol as an antitussive?
Approved as a tablet and effective
How much evidence supports the use of maropitant as an antitussive?
Less established efficacy
In study, they didn’t see an anti-inflammatory effect but the dogs coughed less
How much evidence supports the use of diphenoxylate as an antitussive?
Less established efficacy
Hypothesis is that crosses BBB to affect opioid receptors in medullary cough center
What benefits does furosemide have in managing pulmonary edema in addition to its diuretic effect (that decreases preload)?
Decreases preload by diuretic action
Produces local vasodilatory prostaglandin in the lung
What benefit do opioids have in managing dyspnea besides sedation?
They desensitize CO2 receptors to conver rapid shallow respiration to more efficient slower and deeper respiration
What drug is best suited to decrease pulmonary hypertension without having prominent effects on systemic blood pressure?
Slidenafil (Viagra, Revatio)
What are the benefits of using a glucocorticoid inhaler versus systemic administration? Name one example of an inhaled steroid.
In order to control inflammation, we want the steroids to act locally rather than systemically
Example: Beclomethasone (Beconase) and Fluticasone (Flonase)
Are feline asthma and equine COPD primarily a problem involving inhalation or exhalation?
Exhalation
What is a “heave line” in a horse and why does it occur?
Heave line is a line that is made of a line of abdominal muscles that enlarge in a horse with heaves
What are the most common side-effects of beta-2 agonist bronchodilators?
Tachycardia
Slight muscle tremors in some patients
Lowers serum potassium
Airway inflammation induced with regular inhalation of racemic albuterol, but not with levalbuterol
Explain how to perform an atropine-challenge (or butylscopolamine-challenge) test in equine COPD
Give test dose of atropine IV to see if it improves respiratory effort (diminished heave line)
Response to atropine indicates horse may respond to other bronchodilators
Has been used nefariously by horse traders, Check pupils for dilation.
Primary side effect of concern is ileus
What are the major beta-2 agonists used as bronchodilators?
Albuterol
Levalbuterol
Clenbuterol
Terbutaline
What is albuterol’s route of administration?
Inhaled, oral, or parenteral
What is the major side effect of albuterol?
Airway inflammation induced
What are the major species that albuterol is used in?
Humans, approved in horses
What is levalbuterol’s route of administration?
Inhaled
What are the major species that levalbuterols in used in?
Humans
What is clenbuterol’s route of administration?
Oral
What are the major species that clenbuterol is used in?
Horses
What is terbutaline’s route of administration?
Parenteral
What are the major species that terbutaline is used in?
Humans
Why are glucocorticoids often given to animals receiving chronic beta-2 bronchodilators?
Used to prevent (or return) responsiveness of receptors that have down-regulated from prior chronic use of β2 agonists
What major benefit does theophylline provide in respiratory disease beyond bronchodilation?
Increases the strength of respiratory muscles, especially the diaphragm
Name the three methylxanthine compounds
Caffeine, theobromine, theophylline
How does aminophylline differ from theophylline?
Aminophylline is a water-soluble salt of theophylline (81% theophylline)
What effect does oxygen have on the pulmonary vasculature?
It is a vasodilator
Name two toxic signs most commonly seen with a theophylline overdose
Seizures
Cardiac arrhythmias
Vomiting
For an animal on theophylline, what commonly used antibiotics requires a dosage reduction of the theophylline?
Fluoroquinolones
Erythromycin
Chloramphenicol
What is/are the best method(s) of promoting expectoration?
Stimulation of tubule-acinar glands
Adding moisture: Humidify the air. In hospitals, nebulization or vaporization of the air is performed
You can also hydrate the patient
What are the drugs used a expectorants?
Guaifenesin (glyceryl guaiacolate) Saline expectorants (ammonium chloride, potassium or calcium iodide, sodium or potassium citrate, ammonium carbonate) Volatile oils (eucalyptus and menthol)
What is the proposed MOA of expectorants?
Stimulation of tubule-acinar glands
How effective are drugs used as expectorants?
Not very
There is no effect in dogs. In cats, a dose of 1000 mg/kg po is required for a consistent change
Explain the benefit to an animal with respiratory foam due to pulmonary edema of bubbling oxygen through a 20% ethanol solution
This will act as a surfactant to break up the bubbles therefore improving ventilation
What is the only analeptic drug used in veterinary medicine and what toxicity is associated with its overdose?
Doxapram (Dopram)
It has a very small therapeutic index an repeated doses can cause seizures
What are the primary respiratory side effects associated with antihistamines in any species?
Drying of the respiratory tract
What are the primary respiratory side effects associated with bromide in cats?
Pneumonitis
What are the primary respiratory side effects associated with cisplatin in cats?
Pulmonary edema
What are the primary respiratory side effects associated with nebulized acetylcysteine in any species?
Bronchospasm
