Pathophysiology of the lungs

Question 1

conducting zone

Answer 1

from the nose to the terminal bronchioles.
Does ventilation
NO GAS EXCHANGE!!

Question 2

Respiratory zone

Answer 2

alveoli and respiratory bronchioles

SITE OF GAS EXCHANGE!!!

Question 3

function of the conducting zone

Answer 3

is controlled by sympathetic and parasympathetic nervous system.

1. Parasympathetic (muscarinic receptors)- constrict bronchi which leads to increased resistance of airflow.
2. Sympathetic (B2 receptors)- relaxes bronchi which leads to decreased resistance to airflow.

Question 4

Type 1 pneumocytes

Answer 4

structural, gas exchange

Question 5

Type 2 pneumocytes

Answer 5

secretes surfactant (prevents the alveoli from callapsing)

Question 6

pleura

Answer 6

a sac of mesothelium surrounding each Lung.
Allows for frictionless expansion of the lungs.
Major driving force in ventilation.

Question 7

Costodiaphragmatic recess/ costophrenic angle

Answer 7

space located at the base of the lung.

Common site for plural effusion to settle.

Question 8

tidal volume

Answer 8

volume of air with normal breathing.

Question 9

residual volume

Answer 9

volume of gas remaining in the lungs after maximal expiration.
Helps in keeping alveoli open.

Question 10

forced vital capacity (FVC)

Answer 10

volume that can be expired following maximal inspiration

Question 11

Forced Expiratory volume (FEV1)

Answer 11

maximal volume of air that can be forcefully exhaled within one second following maximal inspiration.

Question 12

normal FEV1/FVC ratio

Answer 12

.8 or 80%

Question 13

dead space

Answer 13

volume of the airways and lungs that does not participate in gas exchange

Question 14

functional dead space

Answer 14

volume of air within the alveoli that does not participate in gas exchange.
air is in the alveoli but there is no perfusion. (ventilation without perfusion).

Question 15

hypercapnia vs hypocapnia

Answer 15

hypercapnia-leads to respiratory acidosis

Hypocapnia- leads to respiratory alkalosis

Question 16

negative intra-pleural pressure

Answer 16

keeps alveoli open and helps to draw air into the alveoli

Question 17

what is the driving force in ventilation

Answer 17

diaphragm is the most important muscle for respiration.

Accessory muscles.

Question 18

ventilation vs perfusion

Answer 18

Base- V < Q. V/Q ratio is going to be low.

Apex- V>Q, so V/Q ratio is going to be high.

Question 19

VQ mismatch

Answer 19

some diseases alter ventilation or perfusion.
Dead space- no perfusion, but great ventilation.V/Q= infinity.
Shunt- no ventilation, but perfusion is great. V/Q=0

Question 20

what causes crackles

Answer 20

pneumonia
fibrosis
CHF
pulmonary edema

Question 21

What causes wheezing

Answer 21

obstructed airway and HF.
Asthma
Pulmonary edema
bronchitis
CHF
Foreign body 
tumor

Question 22

What causes stridor

Answer 22

upper airway obstruction.

partial obstruction of the larynx or trachea

Question 23

What causes pleural rub

Answer 23

inflammation of the pleura.
pneumonia
pulmonary infarction

Question 24

increase negative intra-thoracic pressure

Answer 24

happens what the diaphragm contracts.