pulmo objectives 1-3 - Sheet1 Flashcards
What is oxygenation?
Oxygenation is the process of obtaining O2 from the atmosphere and making it available to body tissues/organs.
How is O2 carried in the serum?
O2 is carried in the serum in two forms: dissolved O2 and hemoglobin-bound O2.
How do O2 and CO2 move across the alveolar-capillary membrane?
O2 moves from atmospheric air into the bloodstream, while CO2 moves from the bloodstream into the lungs to be exhaled.
What factors impact oxygenation?
Poor inspiration, alveolar damage, surfactant production, anemia, diseased tissue, and alveolar surface tension.
What is the function of surfactant?
Surfactant keeps the alveoli open and free of fluid and pathogens.
What conditions impact oxygenation?
Pneumonia, ARDS, pulmonary edema, asthma, pulmonary embolism.
What is ventilation?
Ventilation is the inhalation of air into the lungs and exhalation of air out of the lungs, caused by intrathoracic pressure changes.
What muscles are involved in ventilation?
Major muscles include the diaphragm and external intercostal muscles. Accessory muscles include the sternocleidomastoid and scalene muscles for inspiration, and abdominal and internal intercostal muscles for expiration.
What is the difference between inspiration and expiration?
Inspiration is active, while expiration is passive.
How is ventilation evaluated?
Ventilation is evaluated using pulmonary function tests (PFTs), radiographic studies, VQ scans, and ABGs.
What conditions impact ventilation?
Asthma, emphysema, bronchitis, COPD, pneumothorax, pulmonary fibrosis, sleep apnea, drug-induced respiratory depression, heart failure, CNS disorders, neuromuscular disorders.
What are hyperventilation and hypoventilation?
Hyperventilation is when alveolar ventilation exceeds metabolic demands, leading to hypocapnia. Hypoventilation is when alveolar ventilation is inadequate, leading to hypercapnia.
What are the effects of hypercapnia?
Severe vasodilation, increased intracranial pressure, decreased cerebral perfusion, somnolence, coma, and death.
What are the effects of hypocapnia?
Severe vasoconstriction, decreased cerebral perfusion, somnolence, coma, and death.
What is chest wall compliance?
Chest wall compliance refers to the ability of the chest to expand and contract, facilitated by major and accessory muscles.
What muscles are involved in chest wall compliance?
Major muscles: diaphragm and external intercostals. Accessory muscles: sternocleidomastoid and scalene for inspiration, abdominal and internal intercostals for expiration.
What is lung compliance?
Lung compliance is the ease with which the lungs expand, impacted by lung elasticity and chest wall recoil.
What conditions impact lung compliance?
Pulmonary fibrosis, ARDS, sarcoidosis, flail chest.
What is airway resistance?
Airway resistance refers to any impediment to airflow during inspiration or expiration, impacted by changes in airway diameter or obstruction.
What conditions impact airway resistance?
Asthma, bronchitis, mucous plug, foreign body obstruction.
What is lung perfusion?
Lung perfusion refers to blood flow to lung tissue, impacted by cardiac function, shock, narrowing of blood vessels, or obstruction.
How is lung perfusion measured?
Lung perfusion is measured with VQ scans or radiographic studies.
What is shunting?
Shunting occurs when blood leaves the heart without participating in gas exchange, either anatomically (e.g., ventricular septal defect) or intrapulmonary (e.g., ARDS).
What is dead space?
Dead space is an area of the lung with no perfusion, caused by an obstruction of the blood supply.
