COPD Flashcards
Etiopathogenesis of COPD
- Characterized by expiratory airflow limitation not fully reversible
- Unusual in the absence of smoking or prior history of smoking,e xcept for patients with alpha-1 antitrypsin deficiency
- Elastase-antielastase hypothesis: remains a prevailing mechanism for iths pathophysiology
Hallmark of COPD
Airflow Obstruction
Main risk exposure for COPD
Smoking tobacco
Pathologic Changes in COPD
- Chronic inflammation and structural changes resulting from repeated injury and repair
- Increased number sof specific inflammatory cell types in different parts of the lung
Anatomically defined conditioned characterized by enlargement and destruction of alveoli
Emphysema
Clinical condition characterized by chronic cough and spurum production
Chronic Bronchitis
Condition where the bronchioles and smaller airways are narrowed
Small airway disease
Cardinal symptoms of COPD
- cough
- sputum production, exertional dyspnea
- punctauated by exacerbations (acute worsening of symptoms)
Most common symptoms for COPD
cough and sputum
Signs of COPD
- May be normal in early stages
- Pink puffers (predominantly emphysema): thin, non-cyanotic, prominent use of accessory muscles
- Blue bloaters (predominantly chronic bronchitis): heavy and cyanotic
- “tripod” position”: to faciliate use of accessory muscles
- Signs of hyper inflation: barrel chest, hyperresonance on percussion
- Others: pursed-lip breathing, expiratory wheezing, systemic wasting, weigh loss
- Signs of cor pulmonale (bipedal edema, ascites) in severe cases
- Clubbing is not a sign of COPD
Pink puffers
- predominantly emphysema
- thin, non-cyanotic prominent use of accessory muscle
Blue bloaters
- predominantly chronic bronchitis: heavy and cyanotic
Signs of hyerinflation
- barrel chest
- hyperresonance on percussion
Diagnosis of COPD
- A clinical diagnois of COPD should be considered in any patient who has:
- dyspnea
- chronic cough or sputum production
- history to risk factors for the disease
Risk factors for for COPD
- Tobacco smoke
- smoke from home cooking ang heating fuels
- occupational dusts and chemicals
Spirometry in COPD
- Required to make the diagnosis of COPD
- post-bronchodilator FEV1/FVC <0.70: confirms presence of persistent airflow limitation
- FEV1, FEV1/FVC and all other measures of expiratory airflow are reduced
- TLC, FRC, RV may be increased indicating air trapping
- DLCO may be reduced
Chest Radiograph for COPD
- Useful for excluding other differential diagnoses
- low flattened diaphragms
- Increase in the volume of retrosternal airspace (hyperinflation)
- Hyperlucent lung zones with possible bullae formation and diminished vascular markings
CT Scan for COPD
- Not routinely requested
- Maybe helpful when the diagnosis is in doubt to rule out concomitant diseases
- useful if surgical procedure such as lung volume reduction and diminished vascular markings
Pulse oximetry for COPD
- To evaluate a patient’s O2 saturation and need for supplemental oxygen therapy
- Should be used to assess all stable patients with FEV1 <35% predicte owith clinical signs suggestive of respiratory failure or right heart failure
- If peripheral stauration is <92% arterial blood gases should be assessed
Arterial blood gases
- Resting or exertional hypoxemia
- Increased alveolar-arterial oxygen tension gradient
- In-long standing disease, may have chronically increased arterial PaCO2 but metabolic compensation (increased HCO3) maintains pH to near Normal
Approach to Classification of COPD
- Step 1 : Confirm diagnosis of COPD
- Step 2: Assess Airflow limitation (also by spirometry)
- Step 3: Assess for symproms and risk of exacerbations
Assessing Airflow Limitation (by spirometry)
- The classification is based on severity of airflow limitation in COPD using spirometry (post-bronchodilator FEV1)
- Spirometry should be performed after the administration of an adequate dose of a short-acting inhaled bronchodilator (to minimize variability)
Assessing Symptoms and Risk of Exarcerbations
deined as an acute event chacracterized by worsening of the patient’s respiratory symptoms that is beyond normal day to day variations and leads to a change in medication
Exaerbation
Fequent exacerbation
>= 2 per year
simple measure of breathlessness
Relates well to ther measures of health status and predicts future mortality risks
Modified Medical Reaserch council (mMRC) Questionnaire for Assessng Severity of Breathlessness
Modified Medical Research council (mMRC)
COPD assessment test (CAT)
- Comprehensive assessment of symptoms
- Consist of 8 questions which pertain to symptoms of COPD - patient will give a score (0-5 point rating scale) and the points will be added
Beta 2 Aonists for COPD
- Alters airway smooth muscle tone improvng emptying of the lungs
- Effects usualy wears off 4-6 hours (short acting)
- and >12 hours (long acting)
- Regular treatment with LABA is more effective and convenient than SABA
- appears to provide subjective benefit in acute episodes but is not necessarily helpful in satble disease
- Adverse effectL tachycardia, arrythmia, tremors, hypokalemia
SHORT ACTING
- Salbutamol
- terbutaline
LONG ACTING
- Formoterol
- Salmeterol
- Vilanterol
- Olodaterol
- Indacetrol
Anticholinergics for COPD
(Anti-muscarinic)
- Blocks acetycholine’s effect on muscarinic receptors
- Bronchodilating effect of short acting inhaled antichholinergics last longer than that of short acting B2 agonists
- Improves symptoms and health status and effectiveness of pulmonary rehabilitation and reduces exacerbations
- Adverse effects:
- Dry mouth,bitter metallic taste, arrhythmias
-
SHORT ACTING
- Ipratropium bromdie
- Oxitropium bromide
-
LONG ACTING
- Triotropium
- Umeclidinium
- Glycopyrronium
Methylxantines for COPD
- Acts as nonselective phosphodiesterase inhibitor
- Improves FEV1 and breathlessness when added to salmeterol
- Advserse effects:
- tachycardia, arrhythmias, headache, insomnia
- Example:
- Theophylline
- Aminophylline
- Doxofylline
Inhaled Corticosteroids for COPD
- Adition of ICS to nronchodilator treatment is appropriate for:
- Symptomatic patients with FEV1 <50% predicted (stage III and Stage IV)
- Repeared exacerbations
- Chronic treatment with systemic glucocorticoids should be avoided
- ICS combined with LABA in moderate to very severe COPD is more ffecteive than either component alone
- Adverse effects:
- hoarseness, candidiasis
- EXAMPLES:
- Beclomethasone
- Budesonide
- Mometasone
- Fluticasone
PDE-4 Inhibitors for COPD
- Improves lung function and reduces moderate and severe exacerbations in patients with chronic bronchitis or those whoa re in fixed-dose LABA/ICS combiantions
- Adverse effects:
- Anorexia, weight loss, diarrhea, headache
Antibiotics for COPD
- Long term azithromycin and erythromycin use reduces exacerbations over 1 year
- Azithromycin 250 mg/day or 500 mg 3x/week or erythromycin 500 mg 2x/day for 1 year
Mucolytics/Antioxidants for COPD
- Antioxidants (N-acetylcysteine and carbocysteine) reduce the risk of exacerbations in select populations
Vaccination for COPD
- Influenza vaccine: decrease incidence of lower respiratory tract infections
- PCV13 andPPSV23 are recommended for all >65 years of age
- 23 valent pneumococcal polysaccharide vaccine (PPSV23): reduces incidence of CAP in COPD patients <65 years and FEV1 <40% predicted and in those with commorbidities
- 13 valent conjugate pneumococcal vaccine: efficient in reducing bacteremia and serious invasive pneumococcal disease in the general population >65 years
3 interventions that have been demonstrated to influence the natural history of COPD
- Smoking Cessation
- Oxygen Therapy
- Lung volume Reduction surgery
Biggest impact in the natural history of COPD
Smoking cessation
Only pharmacologic therapy demonstrated to unequivocally decrease mortality rates in COPD
Oxygen
- >15 hours/day (long term oxygen therapy)
Management of Stable COPD
- Main goals:
- Reduction of symptoms
- Reductionof future exacerbations
Non pharmacologic management of COPD
Pharmacologic Management of Stable COPD
- Most are inhaled (proper inhaler technique is important)
- LABAs and LAMAs: preferred over short-acting agents, except for those with only occasional dyspnea
- Patients may be started on a single long-acting bronchodilator therapy
- Long term monotherapy with ICS is NOT recommended
Supplemental Oxygen to COPD patients
- Prescribe oxygen and titrate SaO2 >90% in patients with arterial hypoxemia, defined as:
- PaO2 <55 mmHg or SaO2 <88% or
- PaO2 55-59 mmHg with right heart failure or erythrocytosis
- Recheck and reassess in 60-90 days
Etiopathogenesis in Exacerbations in COPD
- Associated with increased airway inflammation, increased mucus production, and arked gas trapping
- Mainly triggered by respiratory viral infections (others: bacterial infetons, environmental factors)
Key symptom during exacerbations in COPD
Manifestations of Exacerbations in COPD
- Increased dyspnea
- Increased sputum purulence and volume
- Increased cough
- wheezing
- Symptoms usually last between 7-10 days during exacerbations; but 20% of patients do not recover at 8 weeks
Classification of exacerbated COPD among hospitalized patients
most important sign of a severe exacerbation in patients with very severe COPD
Change in metal status
Management of Acute Exacerbations
Management of Severe but NOT life threatening Exacerbations of COPD at the ER
- Assess severity of symptoms, blood gases and chest radiographs
- Administer controlled oxygen therapy and repeat ABG after 30-60 minutes
- Increase doses and/or frequency of use of bronchodilators
- Add oral or IV glucocorticoids
- Consider ntibiotics (oral or occasionally IV) when there are signs of bacterial infection
- Consider non-nvasive mechanical ventilation
Therapy for Acute Exacerbations in COPD
Indications for NON INVASIVE VENTILATION
-
Selection Criteria
- Severe yspnea with use of accessory muscles and paradoxical abdominal motion
- Respiratory acidosis (pH <7.35) and/or hypercapnia (PaO2 >45 mmHg)
- Progressive hypoxemia despite supplemental O2 therapy
-
Exclusion Criteria (presence of any of the following)
- Respiratory arrest
- Cardiovascular instability
- Change in mental status, uncooperative patient
- High aspiration risk
- Viscous or copious secretions
- Recent facial or gastroesophageal surgery
- Craniofacial trauma
- Fixed nasopharyngeal abnormalities
- Burns
- Extreme Obesity
Indications for INVASIVE MECHANICAL VENTILATION
- Unable to tolerateNIV or NIV failure
- Respiratoty or cardiac arrest
- Somnolence, impaired mental status
- Massive aspiration or persistent vomiting
- Persistent inability to remove respiratory secretions
- Severe hemodynamic instability without response to fluids and vasoactive drugs
- Severe venticular or supraventricular arrhythmias
- Life-threatening hypoxemia in those unable to tolerate NIV
Discharge Criteria for COPD
- Inhaled beta-agonist use no more fequent than q4 hours
- Patient is able to walk across room
- PAtient able to eat and sleep without frequent awakening by dyspnea
- Aptient has been clinically stable for 12-24 hours
- Patient (or home caregiver) fully understands the use of medications
- Follow-up plans and home care arrangements have been completed, follow up <30 days following discharge
