applied anatomical concepts

Question 1

what is respiration?

Answer 1

• oxygen conveyed to tissues and cells and the oxidation products, carbon dioxide and water are given off (gaseous exchange)

Question 2

what are the phases of breathing? 2

Answer 2

inspiration

expiration

Question 3

what are the areas of breathing? 2

Answer 3

thoracic

abdominal

Question 4

what are the types of breathing? 2

Answer 4

quiet

forced

Question 5

describe inspiration? 5

Answer 5

• increase in intrathoracic volume= decrease in intrathoracic pressure
• parietal pleura is pulled with the movement of the ribs and diaphragm
• visceral pleura moves with parietal pleura
• lung volume increases
• air moves into the lungs towards lower pressure

Question 6

describe expiration? 5

Answer 6

• decreased intrathoracic volume= increased intrathoracic pressure
• visceral pleura moves with elastic recoil of the lungs
• parietal pleura moves with the ribs and diaphragm as they return to rest
• surface tension between the parietal and visceral pleura prevents the lung from collapsing
• lung volume decreases
• air moves out of the lungs towards lower pressure

Question 7

explain dimension changes of thoracic breathing? 2

Answer 7

• lateral/transverse diameter

- anteroposterior diameter (between anterior and posterior)

Question 8

explain the dimension changes of abdominal breathing?

Answer 8

vertical diameter

Question 9

describe the lateral diameter of the thorax? 4

Answer 9

• Lateral edges of ribs are elevated supero-laterally during inspiration and the lateral diameter of the thoracic cavity increases
• Results in an increase in the transverse or lateral diameter of chest cavity
• Also known as the bucket handle movement
• We use this during thoracic breathing

Question 10

describe the anteroposterior diameter of the thorax? 6

Answer 10

• Anterior ends of ribs are raised during inspiration
• Elevation causes sternum to also be raised
• Movement is facilitated by costal cartilages
• Results in an increase in anteroposterior diameter of the chest cavity
• Also known as pump handle movement
• We use this in thoracic breathing

Question 11

describe the vertical diameter of the thorax? 4

Answer 11

• Via diaphragm which forms floor of the thoracic cavity
• Upon contraction the diaphragm descends 5-10cm compressing abdominal organs
• Increases the vertical diameter of the thorax
• We use this in abdominal breathing

Question 12

what muscles are used in quiet inspiration? 3

Answer 12

• external intercostals
• scalene muscles
• diaphragm

Question 13

what muscles are used in quiet expiration?

Answer 13

• normally a passive process. elastic recoil of the lungs expels air and chest wall falls back into resting position

Question 14

what muscles are used in forced inspiration? 6

Answer 14

• external intercostals
• scalene muscles
• diaphragm
• pectoral muscles
• sternocleidomastoid (SCM)
• latissimus dorsi

Question 15

what are the muscles used in forced expiration? 3

Answer 15

• internal intercostals
• oblique and transverse abdominal muscles
• quadratus lumborum

Question 16

what is the diaphragm? 3

Answer 16

• sheet of skeletal muscle with a central tendon
• pericardium attached to middle of tendon on its superior surface
• diaphragmatic (parietal) pleura lines its superior surface

Question 17

what are the origins of the diaphragm? 3

Answer 17

• sternal- xiphoid process
• costal- costal cartilages of ribs 7-10 and ribs 11-12
• lumbar- medial and lateral arcuate ligaments and lumber vertebral bodies

Question 18

what is the insertion of the diaphragm?

Answer 18

central tendon

Question 19

what are the lumbar attachments of the diaphragm? 3

Answer 19

• lumbar part of diaphragm arises from the medial and lateral arcuate ligaments and from the lumbar vertebral bodies via right and left crura
• the right and left crura meet to form the median acruate ligament to form the aortic hiatus
• fibres of the right crus pass around the oesophagus forming the oesophageal hiatus

Question 20

what are the openings of the diaphragm? 4

Answer 20

• opening for inferior vena cava t8
• oesophageal hiatus T10
• aortic hiatus t12
• the thoracic duct and azygous vein also pass through the aortic hiatus

Question 21

what is the blood supply of the diaphragm?

Answer 21

superior and inferior phrenic arteries

Question 22

what are the actions of the diaphragm? 9

Answer 22

• Alters the volume of the thorax:
• Quiet inspiration (descends 2cm)
• Forced inspiration (descends 7-10cm)
• Aids venous return
• Hiccups
• .
• Alters the volume of the abdomen:
• Urinating and defecation
• Lifting heavy objects (braces vertebral column)
• Childbirth

Question 23

describe the phrenic nerve? 4

Answer 23

• Arises from C3,4,5
• Enters superior mediastinum lateral to the vagus nerve
• Motor: diaphragm (sole supply)
• Sensory: pericardium, parietal pleura (mediastinal and central part of the diaphragmatic), parietal peritoneum, central region of the diaphragm

Question 24

describe a pan coast tumour? 3

Answer 24

• Pancoast tumour is cancer located at the apex of the lung
• If on the left side can cause recurrent nerve compression
• Vocal cord paralysis= hoarseness

Question 25

describe the importance of coronary circulation dominance? 3

Answer 25

• Blockage of the main right or left coronary artery will have different outcomes depending on coronary artery dominance
• Coronary artery dominance is also important when planning a coronary artery bypass graft
• Arteriograms are used to determine coronary artery dominance