Obstructive Lung Disease - COPD Flashcards
3 disorders that can occur in COPD?
Chronic bronchitis.
Emphysema.
Asthma. (note that asthma alone =/= COPD)
Is asthma a disease of children?
No. It’s a disease that often has its onset in childhood, but it’s a lifelong disease.
Is COPD preventable?
Yes - it’s an “enhanced chronic inflammatory response… to noxious particles or gases” - esp. smoking.
(…usually. I don’t know if we would call alpha-1 antitrypsin deficiency preventable, though it is treatable)
3 cardinal symptoms of COPD?
Dyspnea, (esp. with exertion).
Cough.
Sputum production.
If you suspect COPD, what’s the most illustrative test to do?
Spirometry.
What does spirometry testing of someone with COPD yield?
Low FEV1/FVC.
FEV1 declines with age, but when you smoke…
it declines much more rapidly (if one is susceptible to the smoke).
How do measure the severity of COPD?
FEV1/FVC
Is oxygen requirement a good measure of the severity of COPD?
No…
he really hit this point hard… though I’m not sure I fully understand the reasoning here
How does BMI relate to prognosis for COPD?
Surprisingly, the people with higher BMIs live longer.
Cachexia is predicts poor prognosis for COPD.
Characteristic inflammatory cells of COPD?
Macrophages, PMNs, lymphocytes (CD8s).
to be contrasted with those of asthma
Is small airways disease all about the mucus?
No, there’s a lot of mucus, but the lumen is also constructed by mucosal and peribronchial inflammation/fibrosis. (obliterative bronchiolitis)
What’s the deal with the “pink puffer” and the “blue bloater”?
These are supposed to represent the extremes of emphysema vs. chronic bronchitis predominate COPD, but the current thinking is that people have some mix of both.
Reversibility of COPD vs. asthma?
COPD - the loss of lung function is irreversible.
Asthma - the loss of lung function is largely reversible (but fibrotic changes can happen after exacerbation…)
When you think about emphysema having in decreased elasticity / increased compliance, what part of the lung actually has that decreased elasticity?
Think about a reduction in the elasticity of the interstitium. This means there’s less force pulling the airways open, and less force preventing a “barrel chest” from happening.
Why do people with obstructive lung disease hyperventilate (e.g. with exertion)?
Because of air-trapping (can’t exhale quickly enough), tidal volume can’t be increased -> hyperventilation is necessary to achieve adequate respiration. (but this doesn’t work very well)
How is CXR used in the diagnosis of COPD? (important)
It’s not.
CXR / HRCT can show you emphysema, but one can have COPD without having emphysema.
How is diagnosis of COPD made?
Spirometry, history, and physical exam findings that make sense.
Eg. obstructive disease not relieved by albuterol, onset in middle age, Hx of smoking, etc.
Role of vaccines in COPD treatment?
Influenza and pneumococcal vaccines are recommended for most. -prevents exacerbations.
Pharmacologic therapies for COPD include…
(not necessary to know all the things, but you know roughly the order in which therapies are added when severity increases)
(smoking cessation, vaccines, and exercise first!)
Short-acting beta-agonists/muscarinic-antagonists.
Long-acting beta-agonists/mucarinic-antagonist.
Inhaled corticosteroids?
Ttheophylline, prophylactic ABx (azithromycin)?
Surgery?
BIPAP
With oxygen throughout.
(More on this in the pharmacology lecture.)
Hard cutoff for when bronchodilator therapy (both short-acting and long-acting) should be started?
When FEV1 < 60% predicted, should treat.
Treatment between 60-80% is a judgment call.
Do bronchodilators cause acute improvement in COPD?
No, but they actually appear to be beneficial when used longer term.
Problem with using methylxanthines (theophyllline) for COPD?
Very narrow therapeutic index -with bad side effects. (including arrhythmias and seizures!)
Downsides of chronic azithromycin for COPD?
Adverse effects: Hearing loss, arrhythmias.
While helpful after 1 year, quite possible that ABx resistance could develop.
Does exercise help people with COPD?
Yes - as part of “Pulmonary Rehabilitation,” it’s quite effective at improving dyspnea, quality of life, and reducing health care utilization.
Which treatment for COPD has the most impact on survival?
Oxygen therapy, best if 24 hr, continuous.
not sure if this statement is 100% accurate, but he did emphasize how good it is for improving survival
Downside of giving too much O2? How does this work?
CO2 retention.
- Reverses hypoxic vasoconstriction for capillaries of poorly ventilated alveoli -> blood flow is shunted away from well-ventilated alveoli -> less CO2 release.
- Haldane effect (oxyhemoglobin carries less CO2 vs. deoxyHb).
- Reduce minute ventilation -reduced hypoxic drive to breathe.
(The first reason is probably most important.)
Rationale behind lung volume reduction for emphysema?
If the emphysema is relatively focal and apical, resecting the damaged area allows the healthy parts of the lung to expand and function better - and can restore diaphragm architecture for better function.
(Dr. Cooper revived this surgery by carefully selecting patients who were likely to benefit from it.)
BIPAP is nice.
Yeah. If you can avoid intubation, it’s a good thing.
BIPAP = bilevel positive air pressure… maintains positive pressure during expiration
