Cardio-Respiraoty Week Four Flashcards
1
Q
Describe the thyroid cartilage
A
This is the larges cartilage in the larynx. It is forks by two plates of cartilage joined anteriorly to form ‘Adam’s apple’. The vocal cords are located here.
2
Q
Describe the cricoid cartilage
A
This is a complete ring of cartilage forming the inferior border of the larynx. The cartilage is united to tracheal by the cricotrachial ligament
3
Q
Describe the epiglottis
A
This is a thin triangular flap at the entrance to the larynx. . This moves downward when food is swallowed.
4
Q
Describe the arytenoid cartilage
A
This is two pyramid cartilages on cricoid which have the vocal ligaments. This allows a pitch change in the voice.
5
Q
When does the trachea begin?
A
C6
6
Q
Where does the tracheal divide?
A
T4
7
Q
When unites he cartilage rings in the trachea posteriorly?
A
Trachealis muslces
8
Q
What is the epithelium of the trachea?
A
Pseudostratified ciliated columnar epithelium
9
Q
What is present at the division of the trachea?
A
Carina
10
Q
What is the difference between the right and left principle bronchi?
A
Right: vertical, shorter, wider
Left: horizontal, larger and thinner
11
Q
How many secondary (lobar) bronchi are there in each lung?
A
Right: three
Left: Two
12
Q
How many tertiary (segmental) bronchi are there in each lung?
A
They each serve a Bronchopulmonary segment. There is initially ten in each lung but then two in the left fuse to from eight.
13
Q
What is the function of Clara cells?
A
Produce component of surfactant
14
Q
What is the passage of air, starting from the trachea?
A
Trachea - Principle bronchi - secondary (lobar) bronchi - tertiary (segmental) bronchi - bronchioles - terminal bronchioles - respiratory bronchioles - alveolar ducts - alveolar sacs - alveoli
15
Q
What is the epithelium of respiratory bronchioles?
A
Ciliated cuboidal epithelium
16
Q
What are the two types of pneumocytes in the alveoli?
A
Type one: large flattened cells with dark oval nuclei. They make up 95% of area and 40% of number. They function in gas exchange.
Type two: these are cuboidal which represent 5% of area and 60% of number. They produce surfactant and are able to divide to replace damaged cells.
17
Q
What is the difference in shape of type one and two pneumocytes?
A
Type one: squamous
Type two: cuboidal
18
Q
What are the two layers of the pleura?
A
The inner visceral and outer parietal. The pleural cavity is in-between.
19
Q
What are the four areas of the parietal pleura?
A
- Mediastinal
- Cervical
- Costal
- Diaphragmatic
20
Q
What are the two lung recesses called?
A
- Costodiaphragmatic
- Costamediastinal
21
Q
What is the nerve supply to the parietal pleura?
A
This is sensitive to pain, pressure and temperature. It is innervated by the phrenic and intercostal nerves.
22
Q
What is the nerve supply to the visceral pleura?
A
This is not sensitive to temperature, pain of tough, only stretch. It is innervated by the ANS.
23
Q
What is the origin of the diaphragm?
A
L1-3
Xiphoid process
Ribs 6-12
24
Q
What happens when the diaphragm is contracted?
A
This occurs during inspiration. The diaphragm flattens, pushing the abdominal contents down and increasing the height of the thoracic cavity.
25
What is the function of the external intercostals?
These are active during inspiration. They serve to pull the ribs up and causes them to rotate, increasing the depth and width of the chest.
26
What are the three main accessory muslces of inspiration?
- Sternocleidomastoid
- Scalene
- Pectoralis minor
27
What is the function of the internal intercostal during inspiration?
Contraction pulls the rib down, reducing the anterio-posterior and lateral dimension.
28
What is the function of the abdominal muslces during inspiration?
This is mainly the rectus abdominus. When contracted, they pull the ribs, down and this increase the abdominal pressure. The increased pressure forces the diaphragm upwards.
29
Explain the process of inspiration
The volume of lung increases due to the contraction of he diaphragm and intercostals. The ribs move outwards and expand. As the volume increases, pressure decreases to 759mmHg. This causes air to move in as the atmospheric pressure is 760mmHg.
30
Explain the process of expiration
This is a largely passive process and there are no muscular interactions. The muslces will relax and this, in addition to lung elastic recoil, cause intrapulmonary volume to increase and the pressure to increase to 761mmHg.
31
Explain the diffusion of oxygen gas exchange in relation to its partial pressure
When breathing in, the 21pKa oxygen becomes diluted with water vapour from upper airways and carbon dioxide already present. This means the oxygen become 15pKa in the lungs. The veins that reach the heart have an oxygen pressure of 6kPa and therefore, there is a gradient of 15 to 6 in the pulmonary capillary.
32
Explain the diffusion of carbon dioxide gas exchange in relation to its partial pressure
Inspired carbon dioxide is very small but there is always a reservoir in the lungs. The PCO2 is 5pKa in the lungs. Metabolising cells produce carbon dioxide and there is transferred to the blood and reaches the heart at 6pKa. There is a small gradient or carbon dioxide, but carbon dioxide is 20x more soluble than oxygen,
33
What are the three main mechanisms of carbon dioxide transport?
10% dissolved in plasma
20% as carbo-amino haemoglobin
70% as bicarbonate
34
What happens when carbon dioxide reacts with water?
Carbon dioxide will react with water to form carbonic acid. This will then dissociate into bicarbonate and hydrogen.
35
Explain the chloride shift
Bicarbonate will eventually accumulate in the red blood cell and then create a charge imbalance. Therefore, it is substituted for chlorine to balance the charge.
36
What happens to haemoglobin as oxygen leaves to enter the tissues?
Oxygen will usually bind to haemoglobin to form oxyhaemoglobin. When this dissociates, the oxygen goes to the tissues and Hb binds to hydrogen to balance out the pH.
37
What is a globular protein?
A waters soluble protien that forms colloids in water
38
What are the bonds that Fe2+ can form in the heme group of haemoglobin?
- 4 polyphyrin nitrogen bonds
- 1 with a side chain of histidine for stabilization
- 1 with oxygen
39
Describe the structure of haemoglobin
This is a quaternary strucutre with two dimers: alpha beta one and two.
40
Describe the 'taut' state of haemoglobin
This is the deoxy form of haemoglobin. The 2 alpha-beta chain interact via ionic and hydrogen bonds preventing movement. There is low oxygen affinity.
41
Describe the 'relaxed' state of haemoglobin
There is rupture of some ionic and hydrogen bonds between the dimers due to oxygen binding.
42
How many heme groups are present in haemoglobin?
Four
43
What is on the y and x axis of the oxygen-dissociation curve?
```
Y = oxygen saturation
X = oxygen partial pressure (kPa and pO2 or mmHg and PO2)
```
44
How does acidity affect the oxygen-dissociation curve??
As pH decrease, the affinity for haemoglobin and oxygen decreases. The curve will shift to the right.
45
What is the Bohr effect?
Haemoglobin can act as a buffer for hydrogen ions. When hydrogen binds to haemoglobin, it alters the structures, decreasing its oxygen-carrying ability. Thus lowered pH drives oxygen off haemoglobin and makes oxygen available for tissues.
46
What is the effect of carbon dioxide on the oxygen-dissociation curve?
Carbon dioxide will bind to haemoglobin and have a similar effect to hydrogen. When carbon dioxide increase, the curve will shift to the right.
47
What is the effect of temperature on the oxygen-dissociation curve?
Increased temperature will move the curve to the right. Increasing the temperature will dentures the bonds between haemoglobin and oxygen.
48
What is the effect of 2,3-bisphosphoglycerate (2,3 BPG) on the oxygen-dissociation curve?
2,3 BPG s a regulator for binding oxygen to haemoglobin. It decreases the oxygen affinity by binding to deoxyhaemoglobin and stabilising the T state. The pocket that 2,3 BPG binds to on the haemoglobin will have positively charged amino acids that will bind to the negative phosphates of 2,3 BPG. A higher concentration of 2,3 BPG, will move the oxygen-dissociation curve to the right.
49
What is the normal pleural cavity pressure?
-5
50
What is primary spontaneous pneumothorax?
There is no obvious cause and this may happen while undergoing pressure changes, for example scuba diving or climbing. There is a rupture of small sub-pleural blebs ( small thin walled air containing spaces)
51
What is secondary spontaneous pneumothorax?
There is an underlying cause of the spontaneous pneumothorax for example lung diseases
52
What is traumatic pneumothorax?
This in injury causing a pneumothorax
53
What is tension pneumothorax?
The pressure inside the pleural cavity is greater than the atmosphere and this will cause force against the organs.
54
What are some x-ray signs of a pneumothorax?
- increased air
- less vascualr markings
- shrunken lobe
- hyperextended diaphragm
- tracheal deviation
- mediastinal shift
55
Where should simple aspiration occur?
- 4/5th mid-axillary line
| - second intercostal space in mid-clavicular
56
What are the layers of the trachea?
Mucosa: ciliated Pseudostratified epithelium with goblet cells
Submucosa: connective tissue with seromucus glands
Adventitia: connective tissue, c-shape hyaline cartilage
57
What is the difference of epithelium in large and small bronchi?
Large: simple columnar
Small: simple cuboidal
58
Which nucleus controls respiration and receives information from mechanoreceptors and chemoreceptors?
Nucleus Tractus Solitarus
59
What type of drug is fluticasone propionate?
Corticosteroid
60
Which vertebra does the pleural extend to inferiorly?
T12
61
How long after birth does foetal haemoglobin last?
6 months
62
What is the difference of foetal haemoglobin?
It has greater affinity for oxygen as it must bind to the mothers oxygen. There is less interaction with foetal haemoglobin and 2.3-BPG.
In adults, 2,3-BPG will bind to histidine (positive) in haemoglobin, but in foetal haemoglobin, the 2,3-BPG binds to serine (negative). This does not interact as well. This means there is a higher oxygen affinity and the curve moves to the left.
63
What are some signs of heart failure?
- raised jugular venous pressure
- oedema
- hepatic enlargement
- crackles
64
What can referred pain to the right shoulder indicate?
Diaphragm damage: liver, gall bladder, duodenum
65
What is Lidocaine?
Local anaesthetic
66
What rib does the horizontal fissure follow?
Fourth
67
Explain the parasympathetic response on the lungs
The Vagus nerve will bind to he M1 and M3 muscarinic recepotrs. There is acetylcholine release and activation of the receptors. This will activate intracellular G proteins, and then activate the phospholipase C pathway. This increase calcium and hence contraction.
68
In astham, what is the effect of IL-4?
Causes class-switching to IgE
69
What antibody is responsible for class-switching to IgE?
IL-4
70
Theophylline is an xanthine, a drug treatment for astham. What is the mechanism of action?
Blocks the enzyme PDE (Phosphodiesterase), which is responsible for inducing cAMP breakdown. This therefore causes bronchodilation.
71
What are some cellular changes of the alveoli during asthma?
- thickened BM
- mucous gland hyperplasia
- mucous plug
- oedema for mucosa and submucosa
- desquamation of epithelium
- smooth muslce hypertrophy
72
What kind of drug is Beclometasone and budesonide and fluticasone?
Glucocorticoids
73
What do Glucocorticoids inhibit?
NFkP: this means no inflammatory cells can be made
| Phospholipase A2 and COS so inflammatory cells cant be made through arachidonic pathway
74
What is the difference between systolic and diastolic heart failure?
Systolic: heart cant pump enough pump
Diastolic: heart cant fill
75
What happens to the ejection fraction during systolic heart failure?
It falls below 40% as there is less blood pumped out. The normal is between 50-70%
76
What happens to the ejection fraction during diastolic heart failure?
The fraction is normal as both total volume and stroke volume are low.
77
What is the mechanism of action of Montelukast?
This inhibits leukotriene D4 and this prevents airway oedema, contraction and mucous secretion
78
What is the mechanism of action of Zafirlukast?
This inhibits leukotrienes D4 and E4, thus reducing constriction and inflammation.
79
During heart failure, what happens to the kidneys?
They receive less blood and this activates the Renin system. This causes fluid retention and results in more filling and higher preload.
80
What are some causes of left-sided heart failure?
Damage to myocardium, arthrosclerosis, hypertension, dilated cardiomyopathy, aortic stenosis
81
What are hemosiderin-laden macrophages?
These are also known heart failure cells. They appear when blood vessels rupture during heart attack and appear red in colour.
82
What will an increase in pulmonary artery presume cause?
Damage to the right ventricle. Pulmonary oedema
83
How can chronic lung disease cause right sided heart failure?
The hypoxia causing pulmonary arteriole constriction and tis increase pulmonary blood pressure. This causes cor pulmonale.
84
What is cor pulmonale?
abnormal enlargement of the right side of the heart as a result of disease of the lungs or the pulmonary blood vessels.
85
What is the mechanism of action of sacubitril?
Inhibits the enzyme neprilysin which cleaves peptides that cause vasodilation.
86
What other drug used in the combination with sacubitril when treating HF?
Valsartan
87
When do type two pneumocytes appear?
35 weeks
88
What doe Pseudostratified mean?
A pseudostratified epithelium is a type of epithelium that, though comprising only a single layer of cells, has its cell nuclei positioned in a manner suggestive of stratified epithelia. The cells are all attached to the BM.
89
What is the epithelium of epicardium?
Simple squamous
90
What partial pressure does the oxygen enter the lungs at and what does it become after being diluted?
It enters at 21kPa and become 15kPa.
91
What is the partial pressure of oxygen in the blood that enters the heart to become re-oxygenated?
6kPa
92
Explain the partial pressure difference of carbon dioxide in the lungs and from the metabolizing tissue.
Lung: 5ka
| Metabolizing tissue: 6kPa
93
What is the shape of the dissociation curve?
Sigmoidal
94
What is the symbol of oxygen partial pressure on the x-axis of the oxygen -dissociation curve?
PO2 (mmHg)
95
Name four things that push the oxygen-dissociation curve to the right
- increased 2,3-BPG
- increased temperature
- decreased pH
- increased carbon dioxide
96
Why does increasing the temperature decrease haemoglobins affinity for oxygen?
It denatures the bonds between oxygen and haemoglobin.
97
What is the Bohr effect?
When hydrogen binds to haemoglobin (to be buffered), it alters the structure, decreasing the oxygen affinity. This allows oxygen to be used in the tissues.
98
What does PET stand for?
Position Emission Tomography
99
What dye is commonly used in a PET scan?
Fluorodeoxyglucose
100
What is Fluorodeoxyglucose ?
This is a naturally occurring glucose that is commonly used in PET scans. This means the body reacts in a similar way.
101
What enzyme do xanthine's block?
Phosphodiesterase
| An example of a xanthine is theophylline
102
What is the function of leukotriene D4?
This induces smooth muscle contraction
