Chapter 74- COPD Flashcards
What is COPD?
A preventable and treatable disease with some significant extra-pulmonary effects that may contribute to the severity in individual patients. Its pulmonary component is characterized by airflow limitation that is not fully reversible… the airflow limitation is usually progressive and associated with an abnormal inflammatory response of the lungs to noxious particles or gases.
How is emphysema different from COPD?
Emphysema is a destructive process. Classically centrilobular emphysema is a component of COPD. Alternatively, severe panacinar emphysema is associated with α1- antitrypsin deficiency, an enzyme that inhibits neutrophil elastase (ie stops your neutrophils from melting your lung parenchyma)
What are the physiological elements of COPD?
1) chronic inflammation from trachea down to alveolar
- mediated by Neutrophils/CD8+/Macrophages/Lymphocytes
- Differs from ASTHMA which is primarily eosinophils
2) mucous plugging
- Increase in goblet cell proliferation and size, increase mucous production and plugging
3) endothelial barrier damage
- Mucociliary response inhibited
4) centrilobar emphysema
Loss of connective tissue and subsequent airway patency/stenting through expiration via radial support (OBLITERATION)
In the end patients end up with Type 1 & Type 2 respiratory failure (Hypoxemia <<< Hypercapnia) DECREASE in pulmonary vascular bed w/ chronic hypoxia = thickening of the vessel walls Net result = pulmonary hypertension, polycythemia: right- sided heart failure (cor pulmonale)
What is an acute COPD exacerbation?
An event in the natural course of the disease characterized by a change in the patient’s baseline
1) dyspnea,
2) cough,
3) and/or sputum
that is beyond normal day-to-day variations, is acute in onset, and may warrant change in regular medication in a patient with underlying COPD
What are the viral and bacterial causes of acute COPDe?
Common viruses include: rhinovirus, respiratory syncytial virus, coronavirus, and influenza
Bacterial pathogens: H. influenzae, M. catarrhalis, S. pneumoniae, P. aeruginosa.
Remember viral induced tend to be protracted course.
Describe GOLD classification for COPD
1) Mild COPD
FEV1/FVC <70%
FEV1 >= 80% predicted
symptoms may or may not be present
2) Moderate COPD
FEV1/FVC <70%
50%
Name triggers of an AECOPD?
1) Infectious
- Viral:rhinovirus, RSV, coronavirus, influenza virus
- Bacterial: H.influenza, S.pneumonia, M.catarralis, P. aerogunosa
- Atypical bacteria: chlamydia pneumonia, legionella
2) Air pollution:
nitrogen oxide
particulants, dust
3) Other events PTX PE lobar atelectasis CHF pneumonia pulmonary compression trauma non-compliacne iatrogenic
Name 4mimicks of AECOPD?
pneumonia CHF PTX PE lobar atelectasis (plugging/mass) pleural effusion dysrhythmias
What clinical features do you look for to diagnose AECOPD?
Blue bloater and pink puffer - no longer true
Hx: cough with/without expectoration
-increased work of breathing, or air hunger
PE:
- Wheeze,
- altered LOC (irritable somnolence - hypercapnea which often has asterixis with it),
- Right heart failure : JVD and peripheral edema
ED management of AECOPD:
main stay: oxygen, beta agonist, anti-cholinergics and corticosteroids
Mild: O2, MDI/nebulized ventolin and atrovent, consider po steroids, consider po antibiotics
Moderate or severe: O2, nebulized ventolin and atrovent, non invasive ventilation, IV steroids, IV antibiotics
Life threatening: ABC, BVM,Intubation with RSI, In-line ventolin and atrovent, IV steroids, IV antibiotics
What does end-tidal tracing look like in CODPe?
shark tooth - for airway obstruction in capnography tracing
What are the indications for Non-invasive Ventilatory support (i.e. Bipap)?
1 or more of:
1) moderate to severe dyspnea with use of accessory muscles and paradoxical abdominal motion
2) Respiratory rate 25 breaths/min
3) Moderate to severe acidosis (pH<7.35) and hypercapnia (PaCO2>45mmHg)
What are the contraindications for Non-invasive Ventilatory support (i.e. Bipap)?
1 or more of:
1) Respiratory arrest
2) cardiovascular instability
3) uncooperative patient (agitated, or severely somolent)
4) upper airway obstruction
5) high aspiration risk
6) recent facial or gastroesophageal surgery
7) craniofacial trauma
8) non-fitting mask
When to tx AECOPD with antibiotics?
1) any patient who get snorkelled: all intubated and NIPPV patients
2) increased sputum purulence with increased dyspnea or increased sputum volume
What antibiotics do you treat AECOPD?
Antibiotics that cover for bacterial infectious causes: S.pneumonis, M.catarrhalis and H.Influenza (or ps.aerogunosa in previous patients with it)
Abx of choice: Fluoroquinolones 5 days >7-10 days of beta-actams and tetracycline
