pulmo objectives 1-3 - Sheet1

Question 1

What is oxygenation?

Answer 1

Oxygenation is the process of obtaining O2 from the atmosphere and making it available to body tissues/organs.

Question 2

How is O2 carried in the serum?

Answer 2

O2 is carried in the serum in two forms: dissolved O2 and hemoglobin-bound O2.

Question 3

How do O2 and CO2 move across the alveolar-capillary membrane?

Answer 3

O2 moves from atmospheric air into the bloodstream, while CO2 moves from the bloodstream into the lungs to be exhaled.

Question 4

What factors impact oxygenation?

Answer 4

Poor inspiration, alveolar damage, surfactant production, anemia, diseased tissue, and alveolar surface tension.

Question 5

What is the function of surfactant?

Answer 5

Surfactant keeps the alveoli open and free of fluid and pathogens.

Question 6

What conditions impact oxygenation?

Answer 6

Pneumonia, ARDS, pulmonary edema, asthma, pulmonary embolism.

Question 7

What is ventilation?

Answer 7

Ventilation is the inhalation of air into the lungs and exhalation of air out of the lungs, caused by intrathoracic pressure changes.

Question 8

What muscles are involved in ventilation?

Answer 8

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.

Question 9

What is the difference between inspiration and expiration?

Answer 9

Inspiration is active, while expiration is passive.

Question 10

How is ventilation evaluated?

Answer 10

Ventilation is evaluated using pulmonary function tests (PFTs), radiographic studies, VQ scans, and ABGs.

Question 11

What conditions impact ventilation?

Answer 11

Asthma, emphysema, bronchitis, COPD, pneumothorax, pulmonary fibrosis, sleep apnea, drug-induced respiratory depression, heart failure, CNS disorders, neuromuscular disorders.

Question 12

What are hyperventilation and hypoventilation?

Answer 12

Hyperventilation is when alveolar ventilation exceeds metabolic demands, leading to hypocapnia. Hypoventilation is when alveolar ventilation is inadequate, leading to hypercapnia.

Question 13

What are the effects of hypercapnia?

Answer 13

Severe vasodilation, increased intracranial pressure, decreased cerebral perfusion, somnolence, coma, and death.

Question 14

What are the effects of hypocapnia?

Answer 14

Severe vasoconstriction, decreased cerebral perfusion, somnolence, coma, and death.

Question 15

What is chest wall compliance?

Answer 15

Chest wall compliance refers to the ability of the chest to expand and contract, facilitated by major and accessory muscles.

Question 16

What muscles are involved in chest wall compliance?

Answer 16

Major muscles: diaphragm and external intercostals. Accessory muscles: sternocleidomastoid and scalene for inspiration, abdominal and internal intercostals for expiration.

Question 17

What is lung compliance?

Answer 17

Lung compliance is the ease with which the lungs expand, impacted by lung elasticity and chest wall recoil.

Question 18

What conditions impact lung compliance?

Answer 18

Pulmonary fibrosis, ARDS, sarcoidosis, flail chest.

Question 19

What is airway resistance?

Answer 19

Airway resistance refers to any impediment to airflow during inspiration or expiration, impacted by changes in airway diameter or obstruction.

Question 20

What conditions impact airway resistance?

Answer 20

Asthma, bronchitis, mucous plug, foreign body obstruction.

Question 21

What is lung perfusion?

Answer 21

Lung perfusion refers to blood flow to lung tissue, impacted by cardiac function, shock, narrowing of blood vessels, or obstruction.

Question 22

How is lung perfusion measured?

Answer 22

Lung perfusion is measured with VQ scans or radiographic studies.

Question 23

What is shunting?

Answer 23

Shunting occurs when blood leaves the heart without participating in gas exchange, either anatomically (e.g., ventricular septal defect) or intrapulmonary (e.g., ARDS).

Question 24

What is dead space?

Answer 24

Dead space is an area of the lung with no perfusion, caused by an obstruction of the blood supply.

Question 25

What is hyperventilation?

Answer 25

Hyperventilation is when alveolar ventilation exceeds metabolic demands, leading to hypocapnia (low CO2 levels).

Question 26

What is hypocapnia?

Answer 26

Hypocapnia is a low partial pressure of serum CO2 (pCO2), which can occur due to hyperventilation.

Question 27

What is hypoventilation?

Answer 27

Hypoventilation is when alveolar ventilation is inadequate in relation to metabolic demands, leading to hypercapnia (high CO2 levels).

Question 28

What is hypercapnia?

Answer 28

Hypercapnia is a high partial pressure of serum CO2 (pCO2), which occurs due to hypoventilation.

Question 29

What are the effects of severe hypercapnia?

Answer 29

Severe hypercapnia causes vasodilation, increased intracranial pressure, decreased cerebral perfusion, somnolence, coma, and death.

Question 30

What are the effects of severe hypocapnia?

Answer 30

Severe hypocapnia causes vasoconstriction, decreased cerebral perfusion and CSF volume, somnolence, coma, and death.

Question 31

How is ventilation evaluated?

Answer 31

Ventilation is evaluated using pulmonary function tests (PFTs), radiographic studies, ventilation-perfusion nuclear scans (VQ scans), and ABGs.

Question 32

What conditions can impact ventilation?

Answer 32

Asthma, emphysema, bronchitis, COPD, pneumothorax, pulmonary fibrosis, sleep apnea, drug-induced respiratory depression, heart failure, CNS disorders, neuromuscular disorders.

Question 33

What is respiratory failure?

Answer 33

Respiratory failure occurs when the body is unable to maintain adequate oxygenation and/or ventilation. It can be hypercapnic or hypoxic.

Question 34

What defines hypercapnic respiratory failure?

Answer 34

Hypercapnic respiratory failure is defined by a PaCO2 ≥ 50 mmHg and a pH ≤ 7.25 (not compensated).

Question 35

What are the main mechanisms of hypercapnic respiratory failure?

Answer 35

The main mechanisms include respiratory disorders affecting ventilation, CNS disorders (e.g., brainstem injury, opioid overdose), chest wall disorders (e.g., flail chest), and neuromuscular disorders (e.g., myasthenia gravis).

Question 36

What defines hypoxemic respiratory failure?

Answer 36

Hypoxemic respiratory failure is defined by an SpO2 < 80%.

Question 37

What are the main mechanisms of hypoxic respiratory failure?

Answer 37

The main mechanisms include VQ mismatch, shunting, diffusion limitation, and alveolar hypoventilation.

Question 38

What is the difference between respiratory distress and respiratory failure?

Answer 38

Respiratory distress refers to difficulty breathing but with some compensation, while respiratory failure occurs when the body can no longer maintain adequate oxygenation or ventilation.