Dyspnea CBM and Oxford Flashcards
1
Q
What is dyspnea?
A
- subjective sensation
- uncomfortable awareness of breathing.
- Does not correlate with clinical or lab measurements
- Based on stimulation of neuropsychological pathways
- conscious perception of stimuli
- interpretation of symptom in context of prior life experiences
2
Q
Pathophysiology of dyspnea
A
- Stimulation of mechanoreceptors, chemoreceptors, vagal afferents
- impulses transmitted to sensory cortex and respiratory centre in medulla
- Signals sent to motor cortex and respiratory muscles AND within sensory cortex
- = conscious perception of shortness of breath
- Experience of breathlessness affected by:
- previous experiences
- meaning of breathlessness
- mismatch between ventilatory demand and body’s ability to respond
3
Q
Prevalence of dyspnea
A
- COPD 95%
- CHF 61%
- Stroke 37%
- ALS - 50%
- Dementia 70%
- Cancer 46-70%
Depends on underlying disease, comorbidities and stage of disease
4
Q
COPD Risk Factors (CBM)
A
- cigarette smoking (1 ppd- 15% risk of COPD, 2ppd 25% risk)
- passive cigarette exposure
- occupational exposure
- alpha anti trypsin deficiency
5
Q
What abnormalities might you see on a Chest Xray of a person with COPD?
What pulmonary functiont tests confirm the diagnosis?
A
- CXRAY:
- normal
- increase AP diameter of chest
- Hyperinflation
- flattening of diaphragm
- PFTs:
- FVC (lung volume)
- FEV1 (airflow obstruction)
- FEV1/FVC < 70% of the predicted value
- MODERATE COPD FEV1 >/ 50%
- SEVERE FEV1 35-49%
- VERY SEVERE FEV1 34 %
- FEV1 increases by 15% after bronchodilators = significant response
6
Q
What are the management goals in COPD?
A
- To improve symptoms by decreasing airflow obstruction and airway inflammation
- To prevent secondary complications like infection
- To maintain function
- To improve QOL
7
Q
What is the mechanism of action for B2 agonist and an anticholinergic? (CBM)
A
Beta2-agonists
- bronchodilation via stimulation of B2 adrenergic receptors in airways
- Used on as needed basis
- rapid onset, short half life
- SE: tachycardia, anxiety
Anticholingergics
- Bronchodilation via inhibiting cholingeric mediated bronchmotor tone
- inhibits vagally mediated bronchoconstrictions
- REgular initial therapy
- stronger bronchodilator effects, longer half life, fewer SE than B2 agonists
8
Q
Vaccination in COPD
A
- respiratory infection can precipitate airway inflammation - trigger COPDAE
- high risk of infection in COPD
- influenza: secondary bacterial pneumonia
- influenza: increased risk of MI, arrythmia, stroke (cytokines)
- vaccine efficacy 70% reduction in morbidity
- Streptococcus pneumonia : CAP
- pneumococcal vaccine q10 years.
9
Q
Pulmonary rehabilitation for COPD
A
- teaching correct inhaler technique
- breathing and relaxation
- energy conservation
- nutritional guidance
- exercise program
- breathing techniques:
- tripod breathing imrpoves efficiency by improving the length-tension dynamic of diaphragm
- pursed lip breathing slows RR, increases intra-airway pressures
- rehab programs outcomes:
- decrease breathlessness
- imrpoved exercise tolerance
- better QOL
10
Q
Home 02 in COPD
A
COPD patients with daytime hypoxia may have increased survival with 02.
- Continuous 02:
- Pa02 < 55 mmHg or 02 sat < 88% at rest
-
Pa02 56-59 mmHg or 02 sat 89% IF:
- polycythemia
- cor pulmonale
- pulmonary hypertension
- Intermittent 02:
- Pa02 <55 mmHg or 02 sat < 88% during exertion
- Pa02 < 55 mm Hg or 02 sat < 88% during sleep
11
Q
Malnutrition and COPD
A
- respiratory muscle wasting
- weakness
- Re-feeding, reconditiong, anabolic steriods
- pulmonary rehab
- Cachexia treatment
12
Q
What is the 1 year mortality of COPD patients with FEV1 < 1 L?
A
30%
(worse than many cancers)
13
Q
Superior Vena Cava Syndrome: clinical diagnosis
A
- clinical severity:
- degree of narrowing of SVC
- speed of onset
- adequacy of venous collaterals
- dyspnea
- facial, neck, arm swelling
- Facial plethora
- dilation and tortuostiy of veins of upper body
- cyanosis of face.
- orthopnea
- cough
- headaches
- stridor /hoarseness
- nasal congestion/rhinorrhea
- proptosis
- severe: cerebral edema
14
Q
SVC syndrome : diagnostic tests
A
- malignancy > 90% of cases
- NSCLC 50%
- SCLC 25%
- Lymphoma and metastatic lesions (breast most likely) 10%
- Thrombosis of SVC
- CT with contrast
- Tissue diagnosis if needed:
- peripheral biospy
- perc biopsy peripheral lung mass (75%)
- bronchoscopy (50-70% dx yield)
- mediatstinoscopy (90%)
- open lung biospy
15
Q
SVC syndrome : managment
A
- treat malignancy
- radiation
- chemotherapy
- SCLC = chemo fast
- elevate head of bed
- 02
- fan/02
- Dexamethasone 8mg po bid
- case reports only
- do not give BEFORE diagnosis: lymphomas highly sensitive to dex
- Diuretics NOT recommended:
- reduce preload, hypotension and shock, increased thrombosis
16
Q
What are the clinical findings of Airway Obstruction?
A
- tachypnea
- increased WOB, accessory muscle use
- tracheal deviation to IPSILATERAL side of collapse/obstruction
- IPSILATERAL no air entry
- IPSILATERAL absent tactile and vocal fremitus
17
Q
What treatment options exist if there is an endobronchial obstruction?
A
- external beam Radiation
- laser
- electrocautery
- cryotherapy
- endobronchial irradiation
- photodynamic therapy
- tracheobronchial stenting
18
Q
What are the clinical findings of Pleural Effusion?
A
- Tachypnea
- Accessory muscles
- Shallow breathing
- CONTRALATERAL tracheal deviation (fluid pushing it away)
- dulllness to percussion
- decreased tactile and vocal fremitus
19
Q
Pleural Effusion treatment
A
- Thoracentesis
- pleural fluids: cell count, cytology, LDH, protein, pH, culture and sens.
- > 1.5 L may cause pulmonary edema
- Chest tube to drainage:
- Pleurex indwelling catheter
- Pleurodesis:
- sclerosing agent talc to create inflammation
- pleura stick together
