PBL #6 - Asthma/PE Flashcards
1
Q
What are common clinical presentations of asthma?
A
- expiratory wheezing
- dyspnea
- coughing
- Symptoms may be worse at night, and patients typically awake in the early morning hours
- nonproductive cough (cough-variant asthma)
2
Q
What are common clinical presentations of venous thromboembolism?
A
- Unilateral lower extremity swelling
- History of Risk factors:
- Hospitalization with confinement to bed for > 3 days
- Surgery or general anesthesia in last 3 months
- Trauma in last 3 months
- Pregnancy/recent childbirth
- Oral contraceptives (estrogen)
- Travel for more than 4 hours
3
Q
What are common clinical presentations of pulmonary emboli?
A
- Sudden onset chest pain that is worse with inspiration, dyspnea, SOB, tachycardia
- History of Risk factors:
- Hospitalization with confinement to bed for > 3 days
- Surgery or general anesthesia in last 3 months
- Trauma in last 3 months
- Pregnancy/recent childbirth
- Oral contraceptives (estrogen)
- Travel for more than 4 hours
4
Q
What is the PERC Rule or Pulmonary Embolism Rule-out Criteria?
A
- A “rule-out” tool and ALL variables must receive a ‘no’ to be negative.
- Ask the questions: Age>50, HR > 100, O2 stat on room air <95%, prior history of venous thromboemolism, trauma/surgery within 4 weeks, hemoptysis, exogenous estrogen, unilateral leg swelling?
- Pretest probability is < 1% if all are answered as no.
- Sensitivity 97%
- Specificity 23%
5
Q
Diphenhydramine:
- MOA
- Relate drug distribution to physiologic effects
A
- H1 antagonist (1st gen)
- PK: crosses blood-brain barrier → can cause drowsiness
6
Q
Chlorpheniramine:
- MOA
- Relate drug distribution to physiologic effects
- Side effects
A
- MOA: H1 antagonist (1st gen)
- PK: crosses blood-brain barrier
- **1st generation H1 antagonists also have some anti-muscarinic effects→ drying of secretions, GI disturbances, etc.
7
Q
Fexofenadine:
- MOA
- Relate drug distribution to physiologic effects
A
- MOA: H1 antagonist (2nd gen)
- PK: substrate for P-glycoprotein, actively pumped out of blood-brain barrier → less drowsiness
8
Q
Cetirizine:
- MOA
- Relate drug distribution to physiologic effects
A
- MOA: H1 antagonist (2nd gen)
- PK: substrate for P-glycoprotein, actively pumped out of blood-brain barrier (less drowsiness)
9
Q
Loratadine:
- MOA
- Relate drug distribution to physiologic effects
A
- MOA: H1 antagonist (2nd gen)
- PK: substrate for P-glycoprotein, actively pumped out of blood-brain barrier (less drowsiness)
10
Q
Theophylline
- Class
- MOA
- Relate drug distribution to physiologic effects
- Toxicities
A
- Class: Methylxanthine (caffeine is also a member of this class)
- MOA: Controversial. May be an adenosine antagonist. In high doses it’s a phosphodiesterase inhibitor, increases cAMP → AMP. This may cause bronchodilation.
- PK: Very narrow therapeutic index
- Tox: Arrhythmias, nervousness, GI bleeding, tremors, insomnia
11
Q
Cromolyn sodium:
- Class
- MOA
- Relate drug distribution to physiologic effects
- Toxicities
A
- MOA: (may) block Ca2+ receptors in mast cells → no Ca2+ release into cytoplasm → no degranulation of histamine (according to Dynamed)
- (Dr. Trachte mentioned it might be stabilizing K+ channels?)
12
Q
Epinephrine:
- Class
- MOA
- Relate drug distribution to physiologic effects
- Toxicities
A
- Class: Nonselective adrenoceptor agonist
- MOA: beta-1, beta-2, alpha-1 agonist
- Route: inhalant or subcu
- Tox: Because of beta-1 action, cardiac effects include tachycardia, arrhythmias, angina exacerbation
13
Q
Albuterol:
- Class
- MOA
- Relate drug distribution to physiologic effects
- Toxicities
A
- Class: Short-acting beta-2 adrenoceptor agonist (SABA)
- MOA: beta-2 agonist
- Important to not overuse beta agonists because tolerance can develop
- Overuse of beta agonist causes downregulation of the body’s beta receptors
- Tox: Skeletal muscle tremor
14
Q
Salmeterol:
- Class
- MOA
- Toxicities
A
- Class: Long acting beta-2 adrenoceptor agonist
- MOA: beta-2 agonist, slower onset and longer duration than SABAs
- Tox: overuse can lead to tolerance, downregulation of systemic beta receptors. Skeletal muscle tremor.
15
Q
Zileuton
- Class
- MOA
- Toxicities
A
- Class: Leukotriene receptor antagonist
- MOA: 5-lipoxygenase inhibitor, prevents leukotriene synthesis, less leukotriene B4
- Side effect: hepatotoxicity
16
Q
Zafirlukast
- Class
- MOA
A
- Class: Leukotriene Receptor Antagonist
- MOA: blocks the action of the cysteinyl leukotrienes on the CysLT1 receptors
17
Q
Montelukast:
- Class
- MOA:
A
- Class: leukotriene receptor antagonist
- MOA: block cys-LT1-receptors
18
Q
Prednisone:
- Class
- MOA
A
- Class: Corticosteroid.
- MOA: transcriptionally induces lipocortin to inhibit PLA2; thus inhibiting synthesis of cytokines, especially NF-kappaB.
- An important mechanism is recruitment of HDAC2 to the inflammatory gene complex, which reverses the histone acetylation associated with increased gene transcription of Beta 2 receptors.