Obstructive Diseases Flashcards
What is a DDx based on these problems?
Wheezing and nighttime breathing problem
Cough productive sputum
Leg edema
Progressive dyspnea
Significant Smoking history (>70 pyhx)
Some hobby and occupational exposures (limited) to respiratory irritants
- COPD
- Asthma
- CHF
- Lung cancer
- Tracheomalacia
- Pericardial effusion
- Pulmonary embolism
Pt comes in with symtpoms suggestive of obstuctive lung disease, what tests would you order?
- Chest X-ray • EKG
- CBC
- BNP
• Pulmonary Function studies
- Arterial Blood gases
- Echo
What do you see in this image?
HYperlucency, Hyperinflated lung, flattened diaphram
will see increased retrosternal space on side view
Spirometry for obstructed lung disease
Scalloped with normal inspiratory and decreased expiratory
These are all examples of:
- Emphysema
- Chronic Bronchitis
- Bronchiectasis
- Chronic persistent asthma (FEV1 remains abnormal after therapy)
COPD
Three key determinant of diffusion in lungs
The surface area of the lung with contact to diffusing alveoli (VA - Alveolar Volume)
the thickness of the alveolar- capillary membrane (Dm - Membrane Diffusion)
the volume of blood available in the capillary bed of the lung (Vc - Capillary Blood Volume).
What effect does these diseases have on Diffusing capacity?
- Asthma
- Alveolar hemorrhage (acute)
- Intracardiac shunt (left to right)
• Erthyrocytosis
Elevation of DLCO
What causes decrease of DLCO
– Significant Anemia
– Loss of parenchyma in diseases like emphysema.
– Diseases that scar the lung such as pulmonary fibrosis, or sarcoidosis
– Swelling of lung tissue (pulmonary edema) due to heart failure, or due to an acute inflammatory response to allergens (acute interstitial pneumonitis).
– Diseases of the circulation in the lung, such as pulmonary vasculitis or pulmonary hypertension.
Amount of air left in the lungs after a normal expiration. This is a sum of the residual volume which r_equires indirect measurement_ with helium diluation or with body plethysmography)
FRC
____ is the amount of air that can be expired after expiratoin of a tidal volume
____ amount that can be inspired after inspiration of a normal tidal volume
ERV
IRV
___ amount of air inhaled or exhaled in a normal breath
___ the amount of air expired after a maximal inspiration
TV
VC
How do you calculate forced vital capacity
Take TLC - RV
This pt has restrictive lung disease. What is true of their functional residual capacity?
what about maximum flow rate or total volume exhaled?
Decreased functional residual capacity by plethysmography
Decreased maximum flow rate and decreased total lung volume exhaled
What is true of the FEV1 and FVC as well as the ratio in restrictive lung disease?
In restrictive disease the FEV1 and FVC are reduced but the ratio is normal. A decreased ratio is found in obstructive lung disease.
With advanced restrictive disease the _____ level will fall and the _____will rise.
arterial oxygen
carbon dioxide
What happens to antatomic dead space and compliance in restrictive lung disease?
Anatomic dead space remains relatively constant at different lung inflations
The increased elastic recoil of the lung in restrictive lung disease decrease compliance