Respiratory system

Question 1

What muscles are involved in inspiration?

Answer 1

Diaphragm
External intercostal muscles
Scalene muscles
Sternocleidomastoids

Question 2

What muscles are involved in expiration?

Answer 2

Internal intercostals
External and internal obliques
Rectus and transversus abdominus

Question 3

What muscle is this?

Answer 3

Sternocleidomastoid

Question 4

What muscle group is this?

Answer 4

Scalene muscles

Question 5

Name the areas of the diaphragm

Answer 5

Question 6

What are pulmonary surfactants?

Answer 6

Complex of lipids and proteins that line the alveoli to lower surface tension (keeps airways dry), and keep alveoli from collapsing when air is exhaled preventing atelectasis during breathing

Question 7

What is SpO2?

Answer 7

Peripheral blood oxygen saturation levels
Measures the oxygen carrying capacity of the haemoglobin in the blood

Question 8

What is SaO2?

Answer 8

saturation of oxygen in arterial blood in ABG analysis

Question 9

What is PaO2?

Answer 9

pressure exerted by oxygen on the arterial wall shown in ABG analysis

Question 10

What is tidal volume? and what is the normal amount?

Answer 10

Tidal volume is the amount of air that moves in or out of the lungs with each respiratory cycle.

It measures around 500 mL in an average healthy adult male and approximately 400 mL in a healthy female

Question 11

What causes hypercapnia?

Answer 11

Alveolar hypoventilation from slowed resp rate and decreased tidal volume, or from gas trapping and obstructed airflow

Question 12

What measurements determine alveolar ventilation

Answer 12

Respiratory rate x tidal volume

Question 13

What is PEEP?

Answer 13

Positive end expiratory pressure is a pressure applied by the ventilator at the end of each breath to ensure that the alveoli are less likely to collapse

Question 14

What is FRC?

Answer 14

Functional Residual Capacity is the volume of air left in the lungs at the end of a normal expiration. It is the combination of residual volume (RV) and the expiratory reserve volume. In a normal individual, this is about 3L.

Question 15

Label the upper respiratory tract

Answer 15

Question 16

Name the lower respiratory tract

Answer 16

Question 16

What is the conducting zone and respiratory zone?

Answer 16

conducting zones (nose to bronchioles) form a path for conduction of the inhaled gases and respiratory zone (alveolar duct to alveoli) where the gas exchange takes place

Question 16

What is the function of ciliated epithelium and goblet cells?

Answer 16

Ciliated cells form an epithelial lining and provides a propelling force for transport for mucus to keep airways patent. Goblet cells secrete mucin and create a protective mucus layer, involved in immunoregulation.

Question 17

What factors precent the lungs from collapsing?

Answer 17

surfactant and intrapleural pressure

negative pressure in the pleural cavity is less than the atmospheric pressure, to create a suction to keep the lungs inflated

Question 18

Define elastic recoil

Answer 18

The tendency of the lungs to deflate after being stretched during inhalation.
Contributes to FRC

Question 19

Define airway resistance

Answer 19

Change in transpulmonary pressure needed to produce a unit flow of gas through lung airways

Question 20

What is pulmonary compliance?

Answer 20

Pulmonary compliance is a measure of the lung’s ability to stretch and expand.

Change in pressure when a volume is given

Lung Compliance (C) = Change in Lung Volume (V) / Change in Transpulmonary Pressure {Alveolar Pressure (Palv) – Pleural Pressure (Ppl)}.

Question 21

What is transpulmonary pressure?

Answer 21

Transpulmonary pressure is the pressure gradient between the inside alveolar pressure and outside pleural pressure.

It mainly measures the force of lung elasticity at each point of respiration.

Question 22

What is static vs dynamic lung compliance?

Answer 22

Dynamic - airways + parenchyma (gas exchange areas)
Static - parenchyma only

Diseases that affect static compliance are pneumonia, pleural effusion, atelectasis

Diseases that affect dynamic compliance are asthma, airway obstructions, bronchospasm

Question 23

What is external vs internal vs cellular respiration?

Answer 23

External respiration, also known as breathing, involves both bringing air into the lungs (inhalation) and releasing air to the atmosphere (exhalation). During internal respiration, oxygen and carbon dioxide are exchanged between the cells and blood vessels. Cellular respiration is when glucose is broken down to make ATP.

Question 24

What is the muscular mechanism and pressure changes for breathing?

Answer 24

When the lungs inhale, the diaphragm contracts and pulls downward. At the same time, the muscles between the ribs contract and pull upward. This increases the size of the thoracic cavity and decreases the pressure inside. As a result, air rushes in and fills the lungs. When the lungs exhale, the diaphragm relaxes, and the volume of the thoracic cavity decreases, while the pressure within it increases. As a result, the lungs contract and air is forced out

Question 25

What is the average lung capacity in a health adult?

Answer 25

6 litres

Question 26

Where are the peripheral chemoreceptors located?

Answer 26

Aortic body (on aortic arch) and cartoid body (outside bifurcation of carotids)

Question 27

What do chemoreceptors do?

Answer 27

Transmit information about oxygen, carbon dioxide and pH levels

Question 28

Where are central chemoreceptors located?

Answer 28

Medulla and pons

Question 29

Side effects and mechanism for salbutamol?

Answer 29

Relaxes bronchial smooth muscle cells to dilate the airways Short acting Tachycardia, nausea, tremors, anxiety

Question 30

Mechanism and side effects of ipratropium bromide?

Answer 30

Bronchodilation Anticholinergic - blocks secretions Long acting side effects: dry mouth, throat/nasal irritation,

Question 31

Mechanism and side effects of steroids?

Answer 31

Acts in nucleus to stop DNA producing inflammatory chemicals Side effects: High BSL (stops insulin working + pulls glucose from adipose tissue) Osteoporosis Weight gain (water weight)