L12.2 Inflammation and Asthma

Question 1

asthma patients experience an increase in ____ ____ and decrease in _____ ______ _____; breathing out is _____, so the net volume of air breathed in ______

Answer 1

asthma patients experience an increase in RESIDUAL VOLUME and decrease in FORCED EXPIRATORY VOLUME; breathing out is INHIBITED, so the net volume of air breathed in DECREASES

Question 2

describe the asthma presentation.

Answer 2

• the inside lining of the airways becomes red and swollen (inflammation)
• extra mucous (sticky fluid) may be produced
• the smooth muscle around the airways tighten (bronchoconstriction)
• intermittent attacks of wheezing, shortness of breath and regular coughing events
• these lead to an increase in residual volume, and a reduction in forced expiratory volume (ERV/FEV1)

Question 3

what might trigger an asthma attack?

Answer 3

environmental: allergens, smoking, diet, pollution, infections, occupational sensitizers
host: gender, obesity, predisposing genes

Question 4

describe the early and late phases of asthma

Answer 4

early phase: bronchoconstriction
late phase: inflammation (mucus hypersecretion, eosinophilic infitration, elevated lgE levels, subepithelial factors), airway hyper-responsiveness

Question 5

what are preventers and what are relievers/controllers?

Answer 5

relievers/controllers (bronchodilators)

• B2 adrenergic agonists (SABAs and LABAs)
• methylxanthines
• muscarinic receptor antagonists

preventers (anti-inflammatory agents)

• leukotriene receptor antagonists
• glucocorticoids (corticosteriods)
• anti-IgE antibodies

Question 6

Compare and contrast the mechanisms of action of the drug classes used in asthma treatment

Answer 6

see table

Question 7

T/F: the early phase of an asthma attack is caused by smooth muscle constriction of the airways

Answer 7

T

Question 8

T/F: early phase treatment is best done using relievers, which are glucocorticoid based treatments

Answer 8

F (first part T, last part F)

Question 9

T/F: late phase asthma attacks are effectively managed with beta-2 receptor agonists

Answer 9

F

Question 10

T/F: a spacer may be used by asthmatics to improve inhalation of the drug at a constant rate, and reducing loss of tongue, mouth and throat

Answer 10

T

Question 11

In regards to the short acting beta 2 agonists (SABAs) what is its:

• reliever or preventer?
• representative
• mechanism of action
• possible adverse effects

Answer 11

• reliever
• representative: salbutamol
• mechanism of action: short term stimulation of beta 2 receptors on smooth muscle lining the bronchioles; effective in early phase asthma
• possible adverse effects: increased heart rate, muscle tremors, feeling lightheaded or shaky, headache

Question 12

In regards to the long acting beta 2 agonists (LABAs) what is its:

• reliever or preventer?
• representative
• mechanism of action
• possible adverse effects

Answer 12

• reliever
• representative: salmeterol
• mechanism of action: same as SABAs but longer duration of effects; generally prescribed to individuals whose asthma is poorly controlled and who have been on inhaled corticosteroids for more than 3 months
• possible adverse effects; same as SABAs

Question 13

In regards to the methylxanthines what is its:

• reliever or preventer?
• representative
• mechanism of action
• possible adverse effects

Answer 13

• reliever
• representative: theophylline (given orally, iv, in addition to corticosteroids and LABAs)
• mechanism of action: inhibition of PDE, may reduce transcription of inflammatory genes as well; stimulation of CNS and increase breathing rate may be beneficial
• possible adverse effects: cardiac dysrhythmia, GI disturbance, seizures, narrow therapeutic window, P450 metabolism (some antibiotics inhibit P450s, leading to toxic effects)

Question 14

In regards to the muscarinic antagonists what is its:

• reliever or preventer?
• representative
• mechanism of action
• possible adverse effects

Answer 14

• reliever
• representative: ipratropium
• mechanism of action: blockade of M3 receptors, preventing parasympathetic contraction of smooth muscle; can be used with beta 2 agonists or steroids in acute severe asthma
• possible adverse effects: limited as not readily permeable into systemic circulation. bitter taste of inhaled ipratropium. nebulized patients of age may develop glaucoma if using face mask

Question 15

In regards to the leukotriene receptor antagonists (LTRAs) what is its:

• reliever or preventer?
• representative
• mechanism of action
• possible adverse effects

Answer 15

• preventer
• representative: montelukast
• mechanism of action: taken orally to reduce leukotriene activity. relaxation of smooth muscle, no effects on inflammation
• possible adverse effects: some GI irritation, but generally well tolerated

Question 16

In regards to the inhaled corticosteroids (ICS) what is its:

• reliever or preventer?
• representative
• mechanism of action
• possible adverse effects

Answer 16

• preventer
• representative: beclomethasone, diproprionate, budesonide, fluticasone, (oral prednisone and prednisolone)
• mechanism of action: inhibition of release of immune mediators from macrophages, T-cells and eosionophils. This leads to a reduction of mucus secretion and reduced inflammation
• possible adverse effects: oral thrush, increased cataract risk, bone density reduction, glaucoma, reduced growth rate in children