Pulmonary Physiology Flashcards

1
Q

What is the primary function of the pulmonary system?

A

Exchange oxygen and CO2 between the environment, blood, and tissues.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What happens when the pulmonary system is compromised?

A

Reduced energy production and exercise tolerance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the process of ventilation?

A

The process of moving air into and out of the lungs.

TV = 350-500mL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q
  • Normal respiratory rate at rest = ?
  • Tidal volume (TV) at rest = ?
  • How is minute ventilation calculated = ?
A
  • 10-15 breaths per minute
  • 350-500 mL of air inhaled or exhaled at rest
  • Minute Ventilation = Respiratory Rate x Tidal Volume
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Sequence of inhalation

4

A

Sequence of inhalation

  1. Diaphragm pulls down
  2. Lateral Intercostals move lateral and AP
  3. Mid chest comes up and out
  4. Upper chest rises
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What law explains the relationship between gas pressure and volume?

A

Boyle’s Law: Pressure of a gas is inversely proportional to its volume.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the difference between normal ventilation and mechanical ventilation?

A
  • Normal ventilation relies on pressure changes
  • Mechanical ventilation uses external force.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is lung compliance?

A

The ability of the lungs to stretch and expand.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How does emphysema affect lung compliance?

A

Emphysema increases compliance but reduces elastic recoil.

Emphysema is a chronic lung condition that damages the air sacs in the lungs, making it difficult to breathe.

  • It’s a type of chronic obstructive pulmonary disease (COPD)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is lung elasticity?

A

The ability of the lungs to return to their original size after stretching.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What role does surface tension play in lung function?

A

Surface tension helps alveoli to reduce in size during expiration.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the Law of Laplace in relation to alveolar pressure?

A

Alveolar pressure = 2 (Surface tension) / Radius of alveolus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the role of surfactant in the lungs?

A

Surfactant reduces surface tension, preventing alveolar collapse.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the formula for resistance according to Poiseuille’s Law?

A

Resistance = ΔP x Radius / Length of airway x Viscosity of gas.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What effect does the parasympathetic nervous system have on airway resistance?

A

Parasympathetic activation causes airway constriction, increasing resistance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What effect does the sympathetic nervous system have on airway resistance?

A

Sympathetic activation decreases airway resistance by causing bronchodilation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What controls ventilation in the brain?

A

Ventilation is controlled by the brainstem, specifically the medulla oblongata and pons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the components of lung volumes?

8

A
  • Tidal Volume (TV)
  • Inspiratory Reserve Volume
  • Expiratory Reserve Volume
  • Residual Volume (RV)
  • Inspiratory Capacity
  • Functional Residual Capacity
  • Vital Capacity
  • Total Lung Capacity (TLC)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

?

A

Inspiratory reserve volume (IRV): The additional volume of air that can be inhaled after a normal inhalation.

20
Q

?

A

Expiratory reserve volume (ERV): The additional volume of air that can be exhaled after a normal exhalation.

21
Q

?

A

Residual volume (RV): The volume of air remaining in the lungs after a maximal exhalation.

22
Q

?

A

Vital capacity (VC): The maximum amount of air that can be exhaled after a maximal inhalation.

23
Q

?

A

Total Lung Capacity: The maximum amount of air that the lungs can hold.

24
Q

What are the two main functions of gas exchange?

A

Replenish oxygen supply and remove carbon dioxide.

25
Q

What is partial pressure in the context of gas exchange?

A

Partial pressure is the pressure exerted by a specific gas in a mixture of gases.

26
Q

What is Dalton’s Law?

A

The total pressure of a gas mixture is the sum of the partial pressures of each individual gas.

27
Q

What is Henry’s Law?

A

Gas dissolves in liquids in proportion to its partial pressure.

28
Q

What is minute ventilation (VE)?

A

The total amount of air moved in and out of the lungs per minute.

29
Q

What is alveolar ventilation (Va)?

A

The amount of air available for gas exchange in the alveoli.

30
Q

anatomical dead space

vs.

physiological dead space

A

Anatomical dead space: The portion of tidal volume that remains in the conducting airways and doesn’t reach the alveoli.

Physiological dead space: The volume of air in the lungs that does not participate in gas exchange.

31
Q

What is the ventilation-perfusion (V/Q) ratio?

A

The ratio of ventilation (airflow) to perfusion (blood flow) in the lungs.

32
Q

How does gravity affect the V/Q ratio?

A

Gravity causes better ventilation and perfusion matching in the dependent parts of the lungs.

33
Q

What is a V/Q mismatch?

A

A condition where ventilation and perfusion are not matched, leading to impaired gas exchange.

34
Q

How is oxygen transported in the blood?

A

Oxygen is primarily transported in the blood bound to hemoglobin.

35
Q

What is the oxyhemoglobin dissociation curve?

A

A graphical representation of the relationship between oxygen saturation and partial pressure of oxygen.

(a) Hemoglobin and Oxygen:

  • Hemoglobin can carry oxygen, and it picks up oxygen in the lungs where oxygen levels are high.
  • It then releases oxygen in the tissues where oxygen levels are lower.

(b) Curve Shape: The curve has an “S” shape (sigmoidal curve). At the beginning (lower PO2) a small increase in oxygen causes a large increase in hemoglobin saturation. But as PO2 increases further, hemoglobin gets saturated, and the curve levels off because hemoglobin can only carry so much oxygen.

(c) Right and Left Shifts: The curve can shift to the right or left depending on conditions like pH, temperature, and levels of carbon dioxide.

  • A right shift means hemoglobin releases oxygen more easily (happens during exercise, when your muscles need more oxygen).
  • A left shift means hemoglobin holds onto oxygen more tightly (happens in the lungs where oxygen needs to be picked up).
36
Q

What is the role of hemoglobin in oxygen transport?

A

Hemoglobin binds and transports 98% of oxygen in the blood.

37
Q

What is carboxyhemoglobin?

A

Carboxyhemoglobin is formed when carbon monoxide binds to hemoglobin, preventing oxygen binding.

38
Q

How is carbon dioxide transported in the blood?

A

Carbon dioxide is transported dissolved in plasma, bound to hemoglobin, and as bicarbonate.

39
Q

What is the Bohr effect?

A

The Bohr effect describes how increased CO2 and decreased pH reduce hemoglobin’s affinity for oxygen.

40
Q

What factors cause a right shift in the oxyhemoglobin dissociation curve?

A

Increased temperature, CO2, acidity, and 2,3-DPG cause a right shift, reducing oxygen affinity.

41
Q

What is the normal partial pressure of oxygen (PaO2) in arterial blood?

A

80-100mmHg.

42
Q

What is a shift to the left in the oxyhemoglobin dissociation curve?

A

A shift to the left increases hemoglobin’s affinity for oxygen, making it harder to release.

43
Q

What happens during hypoventilation?

A

Hypoventilation leads to increased CO2 levels and respiratory acidosis.

44
Q

What happens during hyperventilation?

A

Hyperventilation leads to decreased CO2 levels and respiratory alkalosis.

45
Q

What is respiratory acidosis?

A

Respiratory Acidosis:

  • A condition where blood pH decreases due to elevated CO2 levels.
46
Q

What is respiratory alkalosis?

A

Respiratory Alkalosis:

  • A condition where blood pH increases due to low CO2 levels.