Anatomy of Coughing

Question 1

Stimulation of sensory receptors in the mucosa of the:

Answer 1

Oropharynx (between hyoid bone and soft palette)
Laryngopharynx (between the hyoid bone, larynx and esophagus)
Larynx
Respiratory tree

Question 2

The response from the CNS aims to rapidly coordinate…

Answer 2

Deep inspiration using the diaphragm (phrenic), intercostal muscles and the accessory muscles of inspiration.
Adduction of the vocal cords to close the rima glottidis (vagus).
Contraction of the anterolateral abdonminal wall muscles
Vocal cords abduct to open the rima glottidis
The soft palette tenses and elevates (vagus)

Question 3

What is the purpose of the contraction of the anterolateral abdominal wall muscles?

Answer 3

To build intra-abdonminal pressure which pushes the diaphragm superiorly and builds up pressure in the respiratory tree inferior to the adducted vocal cords.

Question 4

Why does the soft palate tense and elevate?

Answer 4

To close off the entrance into the nasopharynx and direct the stream of air through the oral cavity as a cough.

Question 5

Coughing is a stimulation in the what?

Answer 5

Coughing is the stimulation of the sensory receptors in the mucosa.

Question 6

What sensory receptors are stimulated in sneezing?

Answer 6

CN V or CN IX

Question 7

What sensory receptors are stimulated in coughing?

Answer 7

CN IX or CN X

Question 8

What are carotid sheaths?

Answer 8

Protective tubes or cervical deep fascia that attach superiorly to the bones of the base of the skull and blends inferiorly with the fascia of the mediastinum.

Question 9

What do carotid sheaths contain?

Answer 9

vagus nerve
internal carotid artery
common carotid artery
internal jugular vein

Question 10

Where is the lower respiratory tract?

Answer 10

below the vocal cords and is lined with respiratory mucosa until the level of the terminal bronchioles and alveoli.

Question 11

Where do motor axons travel?

Answer 11

From the tracheal bifurcation along the branches of the respiratory tree to supply all the mucous glands and bronchial smooth muscle.

Question 12

Where does the pulmonary visceral afferents travel?

Answer 12

From the respiratory tree and visceral pleura to the pulmonary plexus and then follow the vagus nerve to the medulla of the brainstem.

Question 13

What does the pulmonary plexus contain?

Answer 13

Sympathetic axons
parasympathetic axons
visceral afferents (conduct sensory impulses)

Question 14

What happens to the chest dimensions during inspiration?

Answer 14

The diaphragm contracts and descends to increase vertical chest dimension.
The intercostal muscles contract to elevate the ribs and increase chest dimension.
The chest wall pulls the lungs outwards to allow air flow and causes a negative pressure.

Question 15

What are the phrenic nerves?

Answer 15

C3, C4 and C5

Question 16

Where are the phrenic nerves found?

Answer 16

In the neck of the anterior surface of the scalenus anterior muscle, and found in the chest descending over the pericardium anterior to the lung root.

Question 17

What do the phrenic nerves supply?

Answer 17

They supply the somatic sensory and sympathetic axons to the diaphragm and pericardium.

Question 18

What muscles are involved in normal inspiration?

Answer 18

o External intercostal muscles
o Internal intercostal muscles
o Innermost intercostal muscles

Question 19

What muscles are involved in deep/forced inspiration?

Answer 19

Pectoralis Major
Pectoralis Minor
Sternocleidomastoid
Scalenus anterior, Medius and posterior