respiratory system Flashcards
(205 cards)
1
Q
what can the respiratory system by divided into?
A
- upper respiratory tract
- lower respiratory tract
2
Q
what does the upper respiratory tract include?
A
- Nadal cavity
- paranasal sinuses
- pharynx
- larynx (above level of vocal folds)
3
Q
what is the purpose of the upper respiratory system?
A
- to condition inspired air before reaching the lungs
4
Q
what happens to air before reaching lungs?
A
- warmed to body temperate
- humidified
- filtered for particulates
5
Q
what does the lower respiratory tract include?
A
- larynx (below level of vocal folds)
- trachea
- bronchi
- bronchioles
- lungs
6
Q
what is the lower respiratory tract concerned with?
A
- gas exchange
- conducts inspired air to tissues involved in gas exchange
- traps and removes particulates
7
Q
what do the lungs contain?
A
- bronchioles
- alveolar ducts
- alveolar sacs
- alveoli
8
Q
what controls the rhythm of breathing?
A
- respiratory centres of the brainstem
9
Q
where is the respiratory centre located?
A
- lower part of brainstem
- in medulla oblongata
10
Q
what are inspiratory neurones?
A
- active during inspiration
- inactive during expiration
11
Q
what are the neurones active during expiration called?
A
- expiratory neurones
12
Q
what do the neurones automatically maintain?
A
- rhythmic cycling pattern of inspiration and expiration
13
Q
what is the automatic rhythm modified by?
A
- afferent information
14
Q
where does afferent information come from?
A
- chemoreceptors
- the brain
- receptors in the lungs
15
Q
what is the main function of the lungs?
A
- to oxygenate blood by bringing inspired air into close relation with deoxygenated blood in pulmonary circulation
16
Q
what is the appearance of lungs?
A
- light, soft and spongy
- can see dark/black deposits as result of breathing polluted air
17
Q
which lung is usually larger?
A
- right lung
18
Q
why is this lung larger?
A
- middle mediastinum (containing the heart) bulges more to the left than the right
19
Q
what is the location of the lungs?
A
- left and right of thorax
- separated by mediastinum
- surrounded by pleural cavities
20
Q
where does air enter and leave the lungs?
A
- main bronchi (branches of trachea)
21
Q
what do pulmonary arteries deliver?
A
- deoxygenated blood to lungs from right ventricle
22
Q
where does oxygenated blood return?
A
- to left atrium
- via the pulmonary veins
23
Q
what 3 surfaces do the lungs have?
A
- costal surface
- mediastinal surface
- diaphragmatic surface
24
Q
what is the location of costal surface?
A
- close to ribs/ costal cartilages and intercostal spaces
25
what is the location of mediastinal?
- close to the mediastinum arteriorly and vertebral column posteriorly
- contains hilum of lung
26
what is the diaphragmatic surface location?
- sits on diaphragm
27
what are the three borders of the lung?
1. inferior
2. anterior
3. posterior
28
what does the inferior border separate?
- base from the costal surface
29
what does the anterior base separate?
- costal surface from mediastinal surface
30
what is the difference between the anterior border of left and right lung?
- right is relatively straight
- left has deep cardiac notch
31
what does the posterior border separate?
- costal surface from mediastinal surface
32
what is the shape of the posterior border?
- smooth and rounded
33
what structures leave impressions in the spongy surface of lung?
- mediastinal
34
what are the impressions on the right lung?
- groove for superior vena cava
- groove for azygous vein
- groove for oesophagus
- groove for inferior vena cava
- cardiac impression
- diaphragmatic impression
35
what are the impressions on the left lung?
- groove for descending aorta
- groove for aortic arch
- cardiac impression
- diaphragmatic impression
36
what are the lungs made up of?
- lobes
37
what are the lobes separated by?
- fissures
38
which side of the lungs has the most lobes?
right lung (larger as presence of heart projects to the left)
39
how many lobes and fissures does the right lung have?
- 3 lobes
- 2 fissures
40
how many lobes and fissures does the left lung have?
- 2 lobes
- 1 fissure
41
what are the two types of fissures that divide the lungs into lobes?
- horizontal
- oblique
42
what does the oblique fissure separate?
- inferior lobe from superior and middle lobe
43
what does the horizontal fissure separate?
- superior lobe from middle lobe
44
what are the 3 lobes in the right lung?
- superior (upper)
- middle
- inferior
45
what is the superior lobe in contact with?
- anterior thoracic wall
46
where does the superior lobe project into?
- root of the neck
47
what is the middle lobe in contact with?
- anterior and lateral thoracic wall
48
what is the inferior lobe in contact with?
- posterior and inferior thoracic wall
49
why is the position of the lobes important?
- dictates where a stethoscope should be placed to listen to each lobe of lung
50
what lobes does the left lung have?
- superior (upper)
- inferior (lower)
51
what is the superior lobe in contact with?
- upper part of the anterior and lateral thoracic wall
52
where does the superior lobe project into?
- root of the neck
53
what is the inferior lobe mostly in contact with?
- posterior and inferior part of thoracic wall
54
what does the oblique fissure separate?
- inferior and superior lobe
55
where is the lingula found?
- left lung
56
what is the lingula?
- tongue like projection that extends over the anterior surface of the heart
57
what are the roots of the lungs?
- where the lungs attach to the heart and tracheae
58
what is the hilum of the lung?
- where structures that make up the root of lung enter and leave
59
what structures make up the root of the lung?
- pulmonary artery
- two pulmonary veins
- a main bronchus
- bronchial vessels
- nerves
- lymphatics
60
what does the visceral pleura become at the hilum?
- parietal pleura
61
what are the characteristics of bronchi?
- thickest, strongest walls
- strong
- cartilaginous
- don't compress or collapse easily
62
what are the characteristics of pulmonary arteries?
- thinner walls
- elastic walls
- elastic recoil when compressed
63
what are the characteristics of pulmonary veins?
- thin walls
- easily collapsible
- not elastic
- don't retain their tubular shape
64
what is the position of the structures at the hilum?
- pulmonary artery = superior
- pulmonary vein = inferior
- bronchi = posterior
65
where does the apex of the lung lie?
- just above first rib
- level with T1
66
what is the inferior aspect of the lung in contact with?
- diaphragm
67
what happens in quiet respiration?
- inferior margin flung travels around thoracic wall
-follows rib 6 down to rib 8 from vertebral level T10 posteriorly
68
what is posterior oblique fissure?
- in midline
- near spine of vertebra T4
69
what is lateral oblique fissure?
- descends diagonally
- crosses 4th and 5th intercostal space to reach rib 6
70
what is anterior oblique fissure?
- follows rib 6 and its costal cartilage
71
what is the horizontal fissure?
- lies anteriorly
- follows contour of rib 4
72
what is the pleura?
- thin membrane enclosing the lungs
- also lines walls of thoracic cavity
73
what is the parietal pleura?
- associated with walls of cavity
74
what does the parietal pleura line?
- pulmonary cavities
- adherent to thoracic wall, mediastinum and diaphragm
75
what is the pleura associated with lungs called?
- visceral pleura
76
what is the purpose of the visceral pleura?
- covers lungs
- is adherent to all its surfaces
- cant be separated from the lungs
77
are the layers of pleura continuous with each other?
- yes
- they are one giant membrane folding to cover all
78
where is the point of continuum of the pleura?
- the root of the lungs
79
what is the space between the pluera layers called?
- pleural cavity
80
what is potential space?
- cavity that doesn't normally exist in healthy people
- present when two membranes are packed closely together
- has potential to become a space in illness or injury
81
what type of membrane is the pluera?
- serous
- produces serous fluid (lubricating fluid between the layers)
82
what is the function of the pleura and serous fluid?
- allows smooth movement of lungs as they expand and collapse
- provides surface tension keeping contact with thoracic wall
83
what is the parietal pleura divided into?
- costal pleura
- mediastinal pleura
- diaphragmatic pleura
- cervical pleura
84
what does the costal pleura cover?
- internal surfaces of thoracic wall
85
what does the mediastinal pleura cover?
- lateral aspects of mediastinum
86
what does the diaphragmatic pleura cover?
- superior aspect of diaphragm on each side of mediastinum
87
what does the cervical pleura cover?
- extends through superior thoracic aperture forming dome over apex
88
what's costomediastinal recess?
costal pleura is opposed to mediastinal pleura
89
what is costodiaphragmatic recess?
- costal pleura is opposed to diaphragmatic pleura
- largest and most clinically important recess
- deepest after forced expiration and shallowest after forced inspiration
90
what is a real space?
- when significant amount of air or fluid enters the pleural cavity
- causes lung to collapse due to elastic nature of the lung tissue
91
what is a common cause of lung space?
- puncture wound to the thorax
92
what is a pneumothorax?
- air rushing into the pleural cavity
93
what is a hydrothorax?
- accumulation of fluid in the pleural cavity
- may result from pleural effusion (escape of fluid into pleural cavity)
94
what is a haemothorax?
- when blood enters the pleural cavity
95
what causes haemothorax?
- result of injury to major intercostal vessels (usually by fractured rib)
96
how is the lung reinflated?
- by draining fluid from pleural cavity using chest drain
97
what do the bones of the thorax consist of?
- sternum
- 12 pairs of ribs
- costal cartilages
- 12 thoracic vertebra (T1-T12)
98
what do these bones provide?
- attachment points for muscles of respiration
- move to facilitate breathing
- provide protection for vulnerable organs within thorax
99
what does the sternum consist of?
- manubrium
- sternal body
- xiphoid process
100
what do the ribs articulate posteriorly with?
- thoracic vertebra
101
where do the ribs end anteriorly?
- costal cartilage
102
which ribs are true ribs?
ribs 1 -7
103
what does true ribs mean?
- they articulate directly with sternum anteriorly
- has own costal cartilage
104
what are the false ribs?
ribs 8 - 12
105
what does false ribs mean?
- articulate indirectly with sternum anteriorly
- attach to sternum via longer, shared costal cartilages
106
what are the floating ribs?
- ribs 11 and 12
107
what are floating ribs?
- don't articulate with sternum anteriorly
- shorter and pointier
108
what do the thoracic vertebra make up?
- posterior element of thoracic cage
- articulate with ribs and with each other
109
what muscles are involved with ventilation?
- skeletal muscles
110
what is the diaphragm?
- thin, musculotendinous, dome shape muscle
111
what does the diaphragm separate?
- thorax from the abdomen
112
what are the features of the diaphragm?
- large, flat central tendon
- attached to lower ribs and vertebral column
- innervated by right and left phrenic nerves (C3,4,5)
113
where does blood supply to diaphragm originate from?
- intercostal arteries
114
where does venous drainage go to?
- inferior vena cava
115
what 3 major structures travel through the diaphragm?
- aorta
- inferior vena cava
- oesophagus
116
wha does contraction of the diaphragm do?
- flattens it
- increases volume of thorax
- aids inspiration
- rib margins lift and move out
117
video on inspiration and expiration
118
how much does the apex move during quiet breathing?
1-2cm
119
how much does the diaphragm move during deep breathing?
10cm
120
where are the intercostal muscles located?
- in between ribs
121
where are external intercostal muscles located?
- superficially to the internal intercostals
122
where does the blood supply come from?
- intercostal arteries
123
what does venous drain occur via?
- intercostal veins
124
what are they innervated by?
- intercostal nerves
125
what 3 structures travel together in intercostal space?
- intercostal artery, vein and nerve
126
what is the function of external intercostal muscles in inspiration?
- pull ribs upwards and forwards
- cause increase in lateral and anteroposterior diameters of thorax
127
what are the properties of external intercostals?
- fibres run obliquely anteroinferiorly (diagonally forward and down)
- contraction of external intercostals pulls ribs up and out
128
what are the properties of internal intercostals?
- fibres run obliquely posteroinferiorly (diagonally backwards and down)
- contraction of external intercostals pulls ribs down and inward
129
what movement happens in internal intercostals during active respiration?
- pull ribs down and inwards
130
what are the innermost intercostals?
- incomplete and variable
- pass from rib to rib deep to the internal intercostals
- separated from internal by bundle of intercostal blood vessels and nerves
131
what are the accessory muscles of respiration?
- sternocleidomastoid
- pectoralis minor
- scalene muscles
132
what is the function of the accessory muscles?
- assist in expansion of thoracic cavity in forced expiration
- maximise respiratory efficiency
133
what planes do the ribs move in during breathing?
- anteroposterior (forwards and backwards)
- laterally
134
what are the tree like structures embedded in lung tissue?
- vascular tree
- airway tree
135
what is the vascular tree composed of?
- arteries, veins and capillaries
136
what is the function of the vascular tree?
- conducts poorly oxygenated blood to the lungs and returns highly oxygenated blood to the heart
137
what does the airway tree consist of?
- air filled branching tubes
138
what is the function of the airway tree?
- conduct new atmospheric air to the gas exchange surfaces
- return used air to environment
139
what is pulmonary oedema?
- build up of fluid in interstitial space in lungs
- increases diffusion distances of gases between blood and alveoli
140
what is pulmonary oedema usually secondary to?
- left heart failure
- renal failure
- pneumonia
- cirrhosis of liver
141
what does the increased diffusion distance lead to?
- hypoxia
- as the blood loads with less oxygen
142
what are early symptoms of pulmonary oedema?
- shortness of breath
- cough
- disrupted rate and rhythm of breathing
143
what are later symptoms of pulmonary oedema?
- cyanosis
- cough with red foaming sputum
144
what is the initial treatment?
- treating hypoxia with 100% oxygen
145
what is later treatment?
- addresses the underlying cause
146
what is the trachea?
- widest conducting airway
- has smallest cross sectional area
- responsible for most airway resistance
147
how is collapsing prevented?
- by rigs of hyaline cartilage
148
what does the trachea bifurcate into?
- two primary or main bronchi which enter the lung
149
where does the bifurcation of trachea occur?
- vertebral level T4
150
what is vertebral level T4?
- level of sternal angle (angle between manubrium and body of sternum)
- level where trachea bifurcate into 2 main bronchi
- level of arch of aorta
- where second rib articulates with the sternum
151
how does the structure of right and left bronchus differ?
- right = wider, shorter, runs vertically
- left = more horizontal, runs inferior to arch of aorta
152
what do the primary bronchi form?
- trunks of each of the lungs
153
how many times do the bronchi divide?
11 times
154
what do the main bronchi first divide into?
- secondary/lobar bronchi (one per lobe of each lung)
155
what do these then divide into?
- tertiary/segmental bronchi (each supplies different segment of lung)
156
what do the first 17 generations of airway form?
- conducting zone of lower respiratory system
157
where are the bronchioles found?
- around 12th division of the bronchi
158
what are bronchioles?
- small, collapsible passageways with smooth muscle walls
159
what're respiratory bronchioles?
- transition between conducting airways and gas exchanging tissues of the lungs
160
where do the respiratory bronchioles terminate?
- at alveolar ducts which lead to alveoli
161
what do the structures from respiratory bronchioles to alveoli form?
- respiratory zone of lower respiratory system
162
what does each tertiary bronchus supply?
- a different bronchopulmonary segment of lung
163
what are the alveoli?
- primary site of base exchange
- small out pockets that greatly increase the SA for gas exchange
164
how are the alveoli arranged?
- in long lobules (cluster of alveoli surrounded by elastic fibres and network of capillaries)
165
what is a lung lobule?
- cluster of alveoli supplied by a single respiratory bronchiole
- surrounded by connective tissue of the lung
166
what are the properties of the alveoli?
- thin walls (one cell thick)
- basement pentanes fused to endothelium of capillaries surrounding
167
what is the apical surface covered in?
- surfactant
- where the gases dissolve to aid their diffusion
168
what is emphysema?
- condition largely associated with smoking
- where lungs are unable to expel all the air (overinflated usually)
169
what is emphysema caused by?
- gradual damage to alveoli
- usually by irritants or infection
- makes them loose their natural elasticity
170
what are the symptoms?
- chronic hypoxia
- fatigue
- weight loss
- breathlessness
171
what can complicate the disease?
- chronic bronchitis (lungs unable to clear mucus)
172
what is the combination of emphysema and chronic bronchitis called?
- chronic obstructive pulmonary disease (COPD)
173
what are the treatments for emphysema?
- no cure
- early symptoms controlled with bronchodilators
174
what is asthma?
- most common chronic airway disease
175
what happens in asthma?
- conducting airways become restricted as diameter reduces
176
what sort of disease is asthma thought to be?
- immunological
- caused by immune system over-reacting to an antigen that would normally be overlooked
177
what is the inducer for asthma?
- original antigen that elicited an immune response
- acts as allergen
178
what happens in response to this inducer?
- immune system gives inappropriate response resulting in over-reaction
- causes swelling of airways and recruitment of eosinophils
179
what is status asthmaticus?
- an acute asthma attack
180
what triggers status asthmaticus?
- an irritant
181
what is an irritant?
- causes varying degrees of bronchoconstriction
182
what treatment is used for acute asthma attacks?
- bronchodilators like salbutamol (Ventolin)
- prophylactic inhaled steroids (BDP)
183
what are the properties of the upper respiratory tract?
- designed with large SA to warm and moisten inhaled air
184
what are the cavities lined with?
- pseudostratified columnar epithelium
185
what cells do columnar cells have on their surface?
- cilia
186
what is the pseduostratified columnar known as?
respiratory type epithelium
187
what are the walls of trachea and large bronchi supported by?
- rings of hyaline cartilage
- incomplete smooth muscle support
188
what are the cartilage rings replaced with as the airways become smaller?
- cartilage plates
- eventually smooth muscle. becomes the major support
189
what is the bronchial tree lined with?
- respiratory type epithelium in the larger bronchi
190
what are the bronchioles lined with?
- simple ciliated columnar epithelium
- goblet cells are sparse
191
what are bronchioles?
- distal airways
- located between cartilage walled bronchi and where ciliated epithelium ceases
192
what is the site of gas exchange?
- distal respiratory tract
193
what are the most proximal components of the lower respiratory tract?
- respiratory bronchioles
(lined with cuboidal ciliated epithelium)
194
what are the alveolar ducts lined with?
- flattened epithelium
195
what do the alveoli consist of?
- type 1 and 2 pneumocytes
(lie on basement membrane)
195
what does the alveolar wall consist of lots of?
- elastin
196
what does the elastin allow?
- lungs to stretch to accommodate inspired air
- recoil to original shape
- allows air to be expelled
- support
197
what are type 1 pneumocytes?
- thin cells
- allow gaseous diffusion
- flattened cells with flattened nuclei
- joined by tight junctions
- few organelles
198
what do type 1 pneumocytes cover?
- basement membrane
199
what are type 2 pneumocytes?
- secrete surfactant
- rounded
- contain mitochondria
200
what is the purpose of surfactant?
- acts as detergent
- reduces alveolar surface tension
- prevents collapse of alveoli during expiration
- facilitates inspirational expansion
201
what can some type 2 pneuomcytes act as?
- precursor stem cells for type 1 pneumocytes
202
what are alveolar macrophages?
- patrol alveolar air spaces and inter-alveolar septa (walls of alveoli)
- can pass freely between
203
what do alveolar macrophages do?
- phagocytose inhaled debris and pathogens
204
what happens after phagocytosis?
- pass into lymphatic system or adhere to mucous coated ciliated epithelium
- continue up mucociliary escalator to trachea where cleared by coughing
