Pulmonary Function Tests (PFT)
Reasons for decreased FVC - ANSWER-Surgical procedure on lung; areas of collapse;
conditions making the lungs less expandable (fibrosis, CHF, thickened pleura);
obstructive lung disease; problems with the pleural cavity (enlarged heart, fluid in
pleura, tumor); restriction of chest wall; inflation/deflation requires all respiratory and
accessory breathing muscles.
Reasons for decreased FEV1 - ANSWER-Obstructive defects; emphysema, chronic
bronchitis, asthma.
What does it mean if the FVC or FEV1 are reduced in the flow-volume loop? -
ANSWER-There is either obstruction or restriction affecting the breathing.
PFTs help determine 7 things: - ANSWER-1. Presence of disease or abnormal lung
function.
2. Extent of dysfunction.
3. Extent of impairment/disability
4. Progression of disease.
5. Nature of physiological disturbance.
6. Effect or course of therapy.
7. Aid clinical prognosis.
Common PFTs - ANSWER-1. Spirometry
2. Diffusing capacity
3. Body plethysmography
4. Bronchial provocation
5. Maximal inspiratory/expiratory pressure
6. Exercise testing
7. Arterial blood gasses
Spirometry - ANSWER-Measures air flow and volumes.
Flow/volume relationship - ANSWER-Peak flow reaches its maximal level somewhere
near total lung capacity.
As lung volume decreases, resistance increases due to intrathoracic airway narrowing.
What is the primary function of the lungs? - ANSWER-1. Oxygenation of mixed venous
blood.
2. Removal of carbon dioxide from mixed venous blood.
Reasons for decreased FVC - ANSWER-Surgical procedure on lung; areas of collapse;
conditions making the lungs less expandable (fibrosis, CHF, thickened pleura);
obstructive lung disease; problems with the pleural cavity (enlarged heart, fluid in
pleura, tumor); restriction of chest wall; inflation/deflation requires all respiratory and
accessory breathing muscles.
Reasons for decreased FEV1 - ANSWER-Obstructive defects; emphysema, chronic
bronchitis, asthma.
What does it mean if the FVC or FEV1 are reduced in the flow-volume loop? -
ANSWER-There is either obstruction or restriction affecting the breathing.
PFTs help determine 7 things: - ANSWER-1. Presence of disease or abnormal lung
function.
2. Extent of dysfunction.
3. Extent of impairment/disability
4. Progression of disease.
5. Nature of physiological disturbance.
6. Effect or course of therapy.
7. Aid clinical prognosis.
Common PFTs - ANSWER-1. Spirometry
2. Diffusing capacity
3. Body plethysmography
4. Bronchial provocation
5. Maximal inspiratory/expiratory pressure
6. Exercise testing
7. Arterial blood gasses
Spirometry - ANSWER-Measures air flow and volumes.
Flow/volume relationship - ANSWER-Peak flow reaches its maximal level somewhere
near total lung capacity.
As lung volume decreases, resistance increases due to intrathoracic airway narrowing.
What is the primary function of the lungs? - ANSWER-1. Oxygenation of mixed venous
blood.
2. Removal of carbon dioxide from mixed venous blood.
