Lecture

• COPD consists of Chronic Bronchitis and Emphysema
• Chronic bronchitis: chronic irritation of the respiratory tract
• Emphysema: loss of alveolar surface area, compromising gas exchange
• Chronic bronchitis occurs through the thickening of respiratory tract secretions that interferes with gas exchange in the alveoli; this can be due to pollutants/irritants
• S/S of chronic bronchitis: chronic cough, increased susceptibility to infection, chronic SOB and intolerance of physical activity
• Degenerative Changes cannot be reversed and there's no cure for COPD
• Emphysema occurs when proteolytic enzymes cause destruction of alveolar walls; the release of these enzymes increases in response to chronic exposure to irritants
• S/S of Emphysema: difficulty expelling air, chronic SOB and activities of daily living restricted
• Clinical manifestations of Bronchitis is: overweight, right sided heart failure, prone to hypoxemia/hypercapnia and have pulmonary hypertension

  
• Clinical manifestations of chronic emphysema: lots of WOB so pretty skinny and development of a barrel chest
• Obstructive lung diseases increases resistance to airflow while restrictive decreases surface area and compliance
• The 3 S's of asthma are: swelling, spasm and secretions
• Asthma is a respiratory condition characterized by SOB and wheezing.
• Asthma S/S occurs through: acute onset bronchoconstriction, mucosal edema, bronchial mucus and decreased ciliary activity(less clearing of mucus)
• Triggers to asthma is smoke, pollen, stress, cold weather and exercise
• Allergic asthma is when an antibody rxn occurs in the respiratory tract
• Asthma is reversible while COPD is not
• Chemical mediators of inflammation: histamine, ECF-A(Eosinophil Chemotactic factor A), Prostaglandins and leukotrienes. These are responsible for most of the symptoms involved in asthma
• The treatment options for asthma are bronchodilators, anti-inflammatory drugs and antiallergic agents
• Within bronchodilators there are 3 types: sympathomimetics, methylxanthines and anticholinergics
• Antihistamines are of little benefit for asthma; could help for allergic asthma
• Eosinophilic chemotactic factor A is in the lining of the respiratory tract
• Anticholinergic drugs are primarily for COPD but can have some use in asthma. They lower the volume of respiratory secretions and cause mild bronchodilation
• Anticholinergic drugs are used in asthma when other bronchodilators are ineffective or in conjunction with other ones. It has a slow onset and a prolonged action.
• Anticholinergic drugs are ipratropium bromide(Atrovent) and tiotropium(Spiriva)
• Sympathomimetics consist of: Ventolin(salbutamol), Serevent(salmeterol), isuprel(Isoproterenol) and epi
• Formation of prostaglandins is inhibited by NSAIDs
• Leukotrienes are potent bronchoconstrictors and have long term effects
• Isuprel(Isoproternol) is a non-selective beta 1 and 2 agonist
• Ventolin and servent mostly work locally and are selective but can become systemic with increased dosages
• Salmeterol(serevent) has a greater affinity for B2 receptors and they are long acting
• LABAs vs SABAs are short acting vs long acting beta agonists
• Methylxanthines refers to the theophylline, caffeine and theobromine that are naturally found in coffee, tea and cocoa that are used in the treatment of asthma
• Methylxanthines fxn by inhibiting the phosphodiesterase enzyme(Not PDE5) which causes cAMP to accumulate and induce bronchodilation/inhibit release of chemical mediators of inflammation
• Theophylline can be admin PO, IV or rectally
• Methylxanthines are used primarily for maintenance and not really for exacerbations of asthma
• Methylxanthines have a large absorption variability person to person and levels must be monitored closely
• Aminophylline IV solution is given during asthmatic crisis @ a hospital
• Adverse effects of methylxanthines are vasodilation effects(hypotension and flushing), cardiac stimulation effects(tachycardia, arrhythmia) and CNS Stimulation(Insomnia and restlessness)
• Anti-inflammatory drugs consist of corticosteroids and leukotriene inhibitors