Drugs for treating respiratory disease - seminar

Question 1

Main indication for diuretics in small animals?

Answer 1

acute treatment of congestive heart failure,
for cardiogenic pulmonary edema

furosemide

Question 2

Describe Bronchodilators. (4)

Answer 2

・ are beta 2 adrenoreceptor agonists
・ Methylxanthine derivatives
・ Anticholinergic drugs

Main indication is feline asthma.
Relaxation of airway smooth muscle

Question 3

Name an injectable bronchodilator used in vet med.

Answer 3

Terbutaline - injectable

indication: acute bronchospasm in suspected feline asthma,
adverse effects: tachycardia, hypotension

Question 4

Name an inhalatory bronchodilator used in vet med.

Answer 4

Salbutamol - inhaled with a mask

Question 5

What is Theophylline?

Answer 5

・ Methylxanthine derivative, phosphodiesterase inhibitor, alters intracellular calcium levels.

• found in tea, coffee, chocolate etc.

・ Bronchodilator, enhances mucociliary clearance, stimulates the respiratory centre, increases the sensitivity to the PaCO2, increases diaphragmatic contractility, reduces respiratory effort, mild inotropic and diuretic effect

・ given PO tabl/oral suspension - less valuable in ICU setting

・ Mainly used as adjunct therapy for chronic cough caused by tracheitis and bronchitis
associated with tracheal collapse.

・ Adverse effects: GI signs, tachycardia, hyperexcitability

・ Do not use with beta sympathomimetics - increased adverse effects

・ Acts synergistically with steroids - smaller dose of steroid required

Question 6

Describe anticholinergic drugs as bronchodilators.

Answer 6

Not used too frequently for bronchodilation in animals (used more in humans for this indication).

e.g. Atropine, glycopyrrolate

・ Compete with acetylcholine at muscarinic receptor sites.

・ Respiratory actions: antagonize vagally mediated bronchoconstriction and decrease
secretions.

・ Not been studied in the treatment of bronchial disease in animals.

・ Indication: acute respiratory distress due to bronchial disease that is refractory to other drugs.

Question 7

Glucocorticosteroids as bronchodilators.

Answer 7

Dexamethasone, prednisolone

・ More powerful and global anti-inflammatory effect than NSAID.

・ Inhibit metabolism of inflammatory mediators, decrease migration of inflammatory cells into the airway.

・ Acts on beta 2 adrenoreceptors - bronchodilation.

Indications:
・ Acute management of upper airway obstruction/BOAS (tissue edema) and feline asthma (when inj. terbutaline not avail, dexamethasone is used).

・ Long term control of chronic respiratory diseases (feline bronchial disease, canine
chronic bronchitis and eosinophilic lung disease).

Inhaled therapy (fluticasone propionate): metered dose inhaler, spacer with face mask, has delay in the efficacy, so with moderate to severe disease start with oral steroids.

Question 8

Dogs do not have asthma, they have

Answer 8

eosinophilic lung disease.

Question 9

Side effects of steroids are more severe in ? Than in?

Answer 9

Side effects: clinical signs of hyperadrenocorticism (PU/PD, PP)

Cats are relatively resistant to side effects, larger dogs seem to suffer more severe or
noticeable side effects with steroids than do smaller dogs.

Glucocorticoids can cause insulin resistance in cats and thus diabetes.

Question 10

Describe Non-steroidal anti-inflammatory drugs used in treatment of respiratory disease.

Answer 10

・ Do not have clinically significant anti-inflammatory effects in the respiratory tract.

・ With the exception of use as analgesics, are not indicated for treatment of most types of respiratory distress.

・ Should be avoided until cardiovascular stability has been confirmed and the patient evaluated for renal disease.

・ Also antipyretic.

Question 11

Describe antibiotics used in treatment of respiratory disease.

Answer 11

・ Infectious respiratory disease

・ Bacteriology and antibiogram

・ With bronchiectasis, ciliary dyskinesia -
intermittent/pulse/chronic therapy.

Question 12

What is Primary ciliary dyskinesia (PCD) disease?

Answer 12

Primary ciliary dyskinesia (PCD) is usually an autosomal recessive genetic condition in which the microscopic organelles (cilia) in the respiratory system have defective function.

Ciliary dysfunction prevents the clearance of mucous from the lungs, paranasal sinuses and middle ears.

Question 13

Define bronchiectasis.

Answer 13

Bronchiectasis is a long-term condition where the airways of the lungs become widened, leading to a build-up of excess mucus that can make the lungs more vulnerable to infection.

The most common symptoms of bronchiectasis include: a persistent cough that usually brings up phlegm (sputum) shortness of breath.

Question 14

Indications for use of mucolytics:

Answer 14

excessive production of airway secretions associated with chronic inflammatory disease (chronic bronchitis, bronchiectasis, ciliary dyskinesia, viscid secretions associated with pneumonia) etc.

Question 15

Describe N-acetylcysteine as a mucolytic.

Answer 15

・ Decreases the viscosity of both purulent and non-purulent airway secretions to facilitate clearance from the respiratory tract.

・ Nebulization is associated with bronchospasm so only use IV/PO.

・ Indication: thick airway secretions that are not readily cleared and risk airway obstruction.

Question 16

Describe Bromhexine as a mucolytic.

Answer 16

・ Increases the production of serous
mucus within the respiratory tract, thus
thinning secretions and facilitating
clearance by the cilia.

Question 17

Name 2 drugs used as mucolytics.

Answer 17

N-acetylcysteine
Bromhexine

Question 18

Name 2 anticholinergic drugs that could be used as bronchodilators.

Answer 18

Atropine, glycopyrrolate

Question 19

Name 2 Beta 2 adrenoreceptor agonists commonly used as bronchodilators.
Name 1 injectable and 1 inhalatory.

Answer 19

Terbutaline - injectable

Salbutamol - inhaled with a mask

Question 20

Use of Analgesics and sedatives in respiratory disease.

Answer 20

Panting can also be a sign of pain thus analgesia must be covered.

・ Acute treatment especially due panic which can affect respiration.

・ Light sedation using Butorphanol (iv if possible, im okay too) in order to minimize anxiety and ease breathing.

Question 21

Describe antitussive agents.

Answer 21

Cough suppressants

・ Indications: dogs with resolving chronic bronchitis/airway collapse.

・ Should not be used before resolution of inflammation and infection as coughing is a protective mechanism.

・ Dextromethorphan (NMDA receptor antagonist) efficacious in some animals.

・ Narcotic agents (hydrocodone, butorphanol) if more potent suppression of a dry cough is required.

Question 22

Name 2 Narcotic agents that also have antitussive attributes.

Answer 22

hydrocodone, butorphanol

Question 23

Name a NMDA receptor antagonis antitussive used in some animals in some countries.

Answer 23

Dextromethorphan (NMDA receptor antagonist) efficacious in some animals.

Question 24

Answer 24

Stable patient so antibiotics (amoxicillin) monotherapy sufficient.

BAL or even thoracic tap for sample if necessary.

Question 25

Answer 25

terbutaline inj. or dexamethasone if former not available

・ Inhalant salbutamol - only as rescue therapy
・ Alternatives: oral extended release theophylline and terbutaline

Control the airway inflammation with glucocorticoids, taper to the lowest effective dose.

Inhaled GCS (fluticasone propionate) may be used once inflammation is adequately
controlled.

Question 26

Case 3

Answer 26

butorphanol and/or other analgesia
supportive therapies
thoracic drainage

antibiotics
NSAIDs after stabilization and hydration