Describe the pathophysiology of asthma
Reversible increased resistance to airflow due to airway narrowing during attack. Patients have normal physiology between the attacks. Caused by bronchospasm or inflammation.
Airway narrowing in asthma is caused by?
What are the triggering factors for Asthma
Identify the clinical features of asthma
What are the physical exam findings of Asthma between attacks
What are the physical exam findings of Asthma during attacks
Identify the diagnosis criteria for asthma
Decreased Peak flow expiratory rate
FVC, FEV1 and FEV1/FVC decreases
What are CXR diagnostic findings for asthma
What are the ABG diagnostic findings for asthma
Hypocapnia
Mild hypoxemia
Hypocarbia is common
Tachypnea in presence of normal or high CO2 (40@40) = Respiratory Emergency, respiratory failure will occur. Intubation is indicated.
Describe the treatment of asthma
Anti-inflamatory drugs
Bronchodilators
Anti-leukotrienes- Zileuton(Zyflo)
Montelukast (Singulair) and Zafirlukast
Anti-IgE monoclonal therapy
Describe the use of Anti-inflamatory drugs for treatment of Asthma
This drug is used only for prophylaxis and not acute asthma attacks. It can also be used to prevent exercise induced asthma
Cromolyn
Describe the use of bronchodilators for treatment of Asthma
This drug is a PDE inhibitor with a narrow therapeutic index, used as a bronchodilator
theophyline
Describe the use of Anti-leukotrienes- Zileuton(Zyflo) for treatment of Asthma
This drug can cause Dyspnea, arthralgia, chest pain, and fever
Anti-leukotrienes- Zileuton(Zyflo)
Describe the use of Montelukast (Singulair) and Zafirlukast for treatment of Asthma
Blocks the conversion of arachidonic acid to leukotriene
Zileuton (zyflo): 5-lipoxygenase inhibitor
Competitive antagonist of leukotriene on cysteinyl-leukotriene1 receptor
Montelukast (singulair) and Zafirlukast
Describe the use of Anti-IgE monoclonal therapy for treatment of Asthma
Use Omalizumab which binds free IgE
This drug binds free IgE
Omalizumab
Describe the management of acute asthma attack
Describe the management of chronic asthma
Inhaled steroids as maintenance + beta 2 agonist for symptomatic control
Add ipatropium
Consider aminophyline
Short course steroids
3 messenger systems for bronchial smooth muscle tone are?
Beta 2 stimulant via Gs Protein
Nitric oxide via cGMP
Cholinergic muscarinic via IP3