Diagnostics 1.1

Ability of the lungs to perform gas exchange depends on( 4 general functions of PFTs)

• Diaphragm and thoracic muscles expanding the thorax and lungs to produce subatomospheric pressure

• Airways must be unobstructed to allow gas to flow into the lungs and read the alveoli

• O2 and CO2 must be able to get through the alveolar capillary membrane

• Cardiovascular system must get blood through the lungs and ventilated alveoli

Complete evaluation of the respiratory system includes

• Patient History

• Physical Exam

• Radiographic Imaging

• ABGs

• PFTs

PFTs do not diagnosis lung diseases but they

• Point out the presence

• Type of imparament

• How bad the impartment is

• tell you the lung disease

Indications for PFTs

• To find and judge the changes in pulmonary functions

• To evaluate need and judge how good therapy is going

• To perform epidemiologic surveillance for pulmonary disease

• To assess patients for risk for post op pulmonary issues

• To determine pulmonary disability

Contraindications for PFTs

• Patients with unstable cardiopulmonary problems

• Patients who have nausea and have recently vomited because risk of aspiration

• Patients who had recent cataract removal should be delayed because changes in ocular pressure may be harmful to the eye

• Patients with dementia or confusion

• If valid and reliable results cannot be predicated

Which problems below would indicate that you should not perform a PFT

• Hemoptysis( Airway bleeding)

• Pneumothorax

• Myocardial infraction

• Pulmonary embolism

• Acute chest or abdominal pain

Obstructive pulmonary disease

• Primary problem is the airways

• Primary problem is the alveoli

• Gas diffusion may be affected

• Expiration is affected

• Flow rates are used

Restrictive pulmonary diseases

• Primary problem is alveoli

• Primary problem is airways

• Gas diffusion may be affected

• Lung parenchyma and thoracic pump are affected

• Volumes or capacities are measured

Normal PFT measurement is

• 80-120

• 35-49

Severe PFT

• 35-49

• 80-120