Restrictive and Obstructive lung diseases Flashcards
What are the intrinsic restrictive lung diseases?
1. Pneumoconiosis A. Asbestosis 2. Radiation Fibrosis 3. RA 4. ARDS/IRDS 5. Hypersensitivity Pneumonitis 6. Pulmonary Fibrosis A. Sarcoidosis B. Idiopathic C. Eosinophilic Pneumonia 7. Drugs A. Methotrexate B. Amiodarone C. Bleomycin
What are the extrinsic restrictive lung diseases?
- Asthma
- Dz restricting lower thorax/abd volume
A. Obesity
B. Diaphragmatic hernia
C. Ascites - Chest wall deformities
A. Pectus Excavatum
B. Kyphosis
What are examples of obstructive lung diseases?
Asthma Bronchiectasis Bronchitis Chronic obstructive pulmonary disease (COPD) Cystic Fibrosis Bronchiolitis
What is the FEV1/FVC ratio in obstructive lung diseases?
FEV1/FVC ratio < 0.7
Inability to exhale 70% of their breath within one second
Define asthma
Chronic inflammatory disorder of the airways
What are the characteristics of asthma?
Variable and recurring sx’s
Airflow obstruction
Hyperactive (hyper-responsive) airways
What is the epidemiology of asthma?
- Diagnosed by age 7 in 75% of cases
- Childhood asthma: males > females
- By age 40: female adults > male adults
- Blacks > whites
- Death rates highest among black males ages 15-24 yr
What is the pathophys of asthma?
Inflammatory cell infiltration with eosinophils, neutrophils, and T lymphocytes
Plugging of small airways with thick mucus
Collagen deposits beneath basement membrane
Hypertrophy of bronchial smooth muscle
Airway edema
Mast cell activation
What happens to the sensitivity/reactivity in asthma?
Leads to airway hyper-responsiveness (hyperactivity) and ↓ airflow
What are the exacerbating factors for asthma?
- Atopy: atopic dermatitis, excema
- Obesity
- Exercise
- URI
- Gastroesophageal reflux disease (GERD): may have silent reflux, not responding to asthma tx, may respond to proton pump inhibitor and asthma meds
- Changes in weather
- Stress
What common allergens are asst. with asthma?
- Environmental causes
A. Dust mites
B. Animal dander
C. Pollen
What are the sxs of asthma?
- Episodic dyspnea
- Chest tightness
- Persistent cough (↑ am & hs)
- Wheezing
- Increased nasal secretions
- Nasal polyps
- Eczema
What dx studies are used to diagnose asthma?
- Symptomatic adults and children > 5yo
A. Spirometry- useful to distinguish asthma from COPD
-Measurement of FEV in one sec (FEV1) and FVC
B. PFT’s
-↓ FEV1, normal FVC, decreased FEV1/FVC ratio
C. Peak Expiratory Flow Meter (PEF)
When do PFTs improve in asthma pts?
- after trial of bronchodilator
A. Significant reversibility
≥ 12% and 200 ml in FEV1 OR
≥ 15% and 200 ml in FVC after inhaling short acting bronchodilator
What Peak expiratory flow results indicate poorly controlled asthma?
- Comparison with one’s own baseline is most effective at predicting exacerbations
A. 20% change in PEF values from morning to afternoon or from day to day indicates poorly controlled asthma
What are the risk factors for asthma?
- Personal Hx of atopic diseases
- FH of atopy and/or asthma
- Smoking
A. Active or 2nd-hand smoke - Occupational exposure
- Home heating system
What is a positive methacholine challenge (bronchoprovocation testing) test? When is it indicated?
- Useful when asthma is suspected but PFT’s are non-diagnostic
- Positive test
≥ 20% fall in FEV1 at exposure to concentration of 8 mg/ml or less
What are the steps in methacholine challenge test
1.) Perform PFT
2.) Inhale nebulized methacholine
3.) Repeat PFT
4.) Repeat using increasing doses until reaction
20% decrease in FEV1= bronchospasm
5.) Inhale nebulized albuterol to reverse effect
When is methacholine challenge contraindicated?
- FEV1 < 65% of predicted
- MI or CVA w/in last 3 mos.
- Known aortic or cerebral aneurysm
- Uncontrolled HTN SBP>200 or DBP>100
- Pregnancy/nursing mothers
When are ABGs indicated in asthma?
- Typically done if patient in distress
- Normal early in asthma exacerbation
- During severe exacerbations, patients may retain CO2 Respiratory Acidosis
What are the signs of impending respiratory failure?
- Change in level of consciousness
- Cyanosis
- Pulsus paradoxus > 10 mm Hg
A. Abnormally large decrease in systolic BP and pulse wave amplitude during inspiration
B. Normal fall in pressure is less than 10 mmHg - O2 saturation < 90%
- pCO2 > 45 mmHg
What factors impact the decision to hospitalize an asthma pt?
- Duration & severity of sx’s
- Severity of airway obstruction
- Course & severity of prior exacerbations
- Medication use at time of exacerbation
- Access to medical care
- Adequacy of social support
When is a cxr indicated for asthma?
Indicated when ruling out pneumonia or pneumothorax
When is skin testing indicated in asthma pts?
Identifies allergens that may be triggers for asthma
What are the complications asst. with asthma?
- Exhaustion
- Dehydration
- Airway infection
- Tussive syncope
A. Neurally mediated reflex vasodepressor-bradycardia response to cough - Severe asthma attack can be fatal if untreated
What are the 4 components of chronic asthma management?
- Assessing & monitoring asthma severity and asthma control
- Patient education
- Control of environmental factors & co-morbid conditions
- Pharmacologic agents
What are 2 ex of beta 2 agonists used in asthma?
- Albuterol (Ventolin HFA, Proventil HFA, Pro-Air)
2. Levalbuterol (Xopenex)
What is the MOA of beta 2 agonists?
Short acting bronchodilator:
Relax airway smooth muscle prompt increase in airflow (onset of action < 5 mins)
When should beta 2 agonists be used?
- Can be used before exercise in EIB
2. PRN use (rescue inhaler)
What is an ex of a mast cell stabilizer?
Cromolyn (Intal MDI)
What is a mast cell stabilizers used for?
Short term asthma treatment
What are OTC asthma meds?
Ephedrine/guaifenesin (Bronkaid, Primatene Tabs)
What general class of meds are used in long term control of asthma and COPD?
Anti-inflammatory agents
Inhaled corticosteroids
What are examples of inhaled corticosteroids?
Flunisolide (AeroBid) MDI Beclomethasone (Qvar) MDI Ciclesonide (Asmanex) Twisthaler Fluticasone (Flovent) Diskus or HFA Budesonide (Pulmicort) (peds)
What is the first line treatment for long term control of asthma? How do they work?
- Inhaled corticosteroids
A. Reduce swelling and inflammation
What are examples of systemic corticosteroids for short term control of asthma?
Prednisone/Prednisolone oral
Methylprednisolone (Solu-Medrol) IV
When are systemic corticosteroids indicated for short term control of asthma?
- Effective for exacerbations and for patients with poorly controlled asthma
- Reduce edema when inhaled corticosteroid not effective
- Taper dose to minimum dose to control sx’s
- Rapid discontinuation of long term steroids after long term use can lead to adrenal insufficiency
What are examples of long acting beta 2 agonist bronchodilators for asthma?
Salmeterol (Serevent) Diskus
Formoterol (Foradil) caps (Perforomist) sol.
Arformoterol (Brovana ) sol
What are the indications for long acting beta 2 agonist bronchodilators for asthma? How do they Work?
- Provides bronchodilation for up to 12 hrs
- Relaxes airway smooth muscle
- Indicated for long term prevention of asthma sx’s & nocturnal sx’s
What are examples of long acting combined beta 2 agonist and inhaled steroids bronchodilators for asthma?
- Fluticasone/salmeterol (Advair)
- Budesonide/formoterol (Symbicort)
- Mometasone/formoterol (Dulera)