Respi anat, physio, patho Flashcards
1
Q
What are the lobes and fissures of the right lung
A
Superior lung
Horizontal fissure
Middle lobe
Oblique fissure
Inferior lobe
2
Q
What are the lobes and fissures of the left lung
A
Superior lobe
Oblique fissure
Inferior lobe
3
Q
What is the arrangement of structures of the hilum of the right lung
A
Bronchus
Artery
Vein
4
Q
Which regions do the lungs end at
A
Midclavicular T6
Midaxillary T8
Paravertebral T10
5
Q
What is the arrangement of structures of the hilum of the left lung
A
Artery
Bronchus
Vein
6
Q
What is the reflection of the parietal pleura
A
Extends 2cm > clavicles to root of neck
Meet behind sternal angle at CC 2-4
Right = Runs behind sternum until CC6
Left
- Diverges 1 cm from sternum at CC6
- Curves laterally at rib 8 midclavicular
- Rib 10 midaxillary
- Rib 12 paravertebral
7
Q
Which regions does the pleura end at
A
Midclavicular T8
Midaxillary T10
Paravertebral T12
8
Q
What is the innervation of the visceral pleura
A
Vagus nerve
Sensitive to stretch and chemical stimuli
9
Q
What is the innervation of the parietal pleura
A
Intercostal nerves => costal parts
Phrenic nerves => Mediastinal part (C3-5)
10
Q
What are the borders of the trachea
A
C6 - T4/5
11
Q
What are the features of the trachea
A
C-shaped hyaline cartilage rings
Recurrent laryngeal nerves
12
Q
Which nerve supplies the diaphragm
A
Phrenic nerve (C3-5)
13
Q
What is the significance of the tracheal cartilage rings being C-shaped
A
Allows oesophagus to expand posterior to the trachea
14
Q
What structures pass through the diaphragm and at what positions
A
T8 = IVC
T10 = Oesophagus & Vagus nerve
T12 = Thoracic aorta, Thoracic duct, Azygos vein
15
Q
What are the different fibres of the phrenic nerve
A
Motor innervation = Entire diaphragm
Sensory innervation = Pericardium & Pleura
Sympathetic innervation = Blood vessels
16
Q
Where is diaphragmatic pain referred to
A
Root of neck and over shoulder
17
Q
What are the parts of the sternum
A
Manubriumm
Sternal body
Xiphoid process
18
Q
What is the position of the sternum angle
A
Rib 2, T4/5
19
Q
What are the floating ribs and their functions
A
11-12
Protection to kidneys & other posterior organs
20
Q
What blood vessels run alongside the sternum
A
IMA / IMV
21
Q
What are the true ribs and their function
A
1-7 = costal cartilage bound to sternum
Provide structural support to thorax
22
Q
What are the false ribs and their function
A
8-10 = connects to costal cartilage of above ribs
Provide flexibility allowing respiratory movement
23
Q
What are the atypical ribs and their different features
A
Rib 1 = Short, broad, flat w grooves for subclavian vessels
Rib 2= Larger than 1st
Rib 10 = Single facet for T10 articulation
Rib 11-12 = Short, no neck or tubercle, single facet
24
Q
What are the typical ribs and their features
A
Ribs 3-9
Double faceted head, neck, tubercle & shaft
25
Describe the venous drainage of the thorax
Anterior IC veins - IMV
Posterior IC veins -> Azygos system/ Brachiocephalic
26
Which part of the vertebrae contains the nerves
Vertebral foramen
27
How do intercostal muscles run
Internal = Downwards backwards
External = Downwards forwards
28
What is the arrangement of the collateral branches in the intercostal spaces
Outward (Rib) -> Inward (Muscle)
Vein Artery Nerve
29
Describe arterial blood supply of the thorax
Subclavian
- IMA -> AIA
- Costocervical trunk -> PIA
30
Where it a chest tube inserted
5th IC space, midaxillary
31
What is the use of needle decompression and where is the position
Emergency relief of pressure on collapsed lung
2nd IC space, midclavicular
32
What makes up the conducting portion of the respiratory tract
Nasal cavities -> Pharynx -> Larynx -> Trachea -> Bronchi -> Bronchioles -> Terminal bronchioles -> Respiratory bronchioles
33
What is the histology of vocal cords and lingual surfaces
Stratified squamous epithelium
33
What is the respiratory portion of the respiratory tract
Respiratory bronchioles -> alveolar ducts -> alveolar sacs -> alveoli
34
What is the histology of respiratory epithelium
Pseudostratified ciliated columnar cells with goblet cells, brush cells and basal cells
35
What are the different pneumocytes and where do they reside
In alveoli
Type I = Simple squamous alveolar epithelium => allows efficient gas exchange
Type 2 = Produces surfactant => Decreases surface tension and prevents collapse
36
Describe the changes and muscle movements that occur during inspiration
Diaphragm and EICM contract
Chest cavity expands
Intrathoracic V increases
P(thorax) & P(pleural cavity) decrease
Lungs expand
Inflow of air
37
Describe the changes and muscle movements that occur during expiration
Diaphragm and EICM relax
Chest cavity recoils
Intrathoracic V decreases
P(thorax) & P(pleural cavity) Increase
Lungs recoil
Outflow of air
38
How is ventilation regulated
Peripheral chemoreceptors in aortic and carotid bodies detect mainly hypoxia => hyperventilation
Central chemoreceptors in medulla detect low pH and hypercapnia => hyperventilation
39
What are the different ventilation volumes
TV = Normal breath volume
IRV = Extra air entering lungs w max inspiration
ERV = Extra air exiting lungs w max expiration
RV = Air left in lungs after max expiration
40
What is vital capacity
TV + ERV + IRV
41
What is total lung capacity
VC + RV
42
What is minute ventilation
TV x RR
43
What is alveolar ventilation
(TV - dead space) x RR
44
What is physiological dead space
Air that reaches alveoli that doesn't undergo gas exchange
45
What is meant by compliance and what can affect it
Stretchability of lungs
Surfactant, fibrosis
46
What affects airway resistance
Size of airway (bronchodilation/constriction)
Mucus accumulation
47
What are the different components of spirometry
FEV1 = Forced expiratory volume exhaled 1s after full inspiration
FVC = Forced vital capacity = Total volume expired forcefully after full inspiration
FEV1/FVC = Reflects changes in compliance & airway resistance
48
How do restrictive diseases affect spirometry
Decrease compliance and increase recoil
FEV1/FVC increase
- High recoil => FEV1 increase
- Overall lung volume decrease
49
How do obstructive diseases affect spirometry
Increase airway resistance
FEV1/FVC decrease
- Expiration slowdown => FEV1 decrease
- Incomplete expiration => FVC decrease
50
What affects diffusion during gas exchange
Partial pressures of gases (difference drives diffusion)
Solubility of gases (more soluble = faster)
Thickness of barrier (Thinner = faster)
Surface area of barrier (More SA = faster)
51
What factors affect blood flow
Volume eg posture/ pul. arterioles muscular tone
Rate eg exercise increase rate
52
Compare the difference in blood flow between foetus and adult
Adult = Low P and high flow
Foetus = High P and low flow
53
How is O2 transported
Hb or dissolved in blood
54
How is CO2 transported
CO2 => HCO3- in RBCs
Bound to proteins eg Hb
Dissolved in blood pCO2
55
What is shunt and what can cause it
Q > V = wasted perfusion
eg atelectasis/pneumonia
56
What is dead space and diseases that can cause it
V > Q = wasted ventilation
eg. pul embolism / decrease CO
57
What can cause rhinitis
Infective = Rhinovirus, Influenza, RSV
Allergic = Type I Hypersensitivity to irritants
58
What are the complications of repeated/ persistent rhinitis
Nasal polyps
Sinusitis
59
What are the causative organisms of sinusitis and corresponding treatment
S. pneumo/ H. inf => Amoxicillin/ Co-amoxiclav
60
What is the pathophysiology of sinusitis
Mucosal oedema => Impaired secretion drainage => bacterial infections => possibly spread to meninges
61
What is the treatment for sinusitis
Antihistamine and decongestant
62
What are the neoplasms that can occur in the nasal region
Benign
- Squamous papilloma
- Sinonasal papilloma
Malignant
- Melanoma
- Adenoma
- Squamous cell carcinoma (m/c)
- Transitional cell carcinoma
63
What are risk factors of NPC
EBV at young age
Family history
Salt preserved foods
64
What are some symptoms of NPC
Epistaxis
Nasal obstruction
Serous nasal discharge
Spread to cervical lymph nodes
CN6 invasion => Diplopia
Eustachian tube obstruction => Secretory otitis media => Tinnitus and hearing loss
65
What are the types of NPC
Keratinising (Type I)
Non-keratinising differentiated (Type II)
Non-keratinising undifferentiated (Type III)
66
What are the characteristics of Keratinising NPC
Squamous cell carcinoma
a/w smoking and alcohol
Least responsive to radiotherapy
67
What are the characteristics of Non-keratinising NPC
Differentiated (Type II)
Undifferentiated (Type III)
- Abundant, non-neoplastic , lymphocytic infiltrate amongst undifferentiated neoplastic cells
- Neutrophilic infiltrate
Both responsive to treatment
68
What is done for NPC screening
EBV IgA antibody
Nasoendoscopy
69
What is CROUP also known as
Laryngotracheobronchitis
70
What do patients with croup present with
Cough and stridor
71
What are the complications of CROUP
Swelling of epiglottis and vocal cords -> airway obstruction (Mainly in children)
72
What are the causative organisms of CROUP
RSV, Parainfluenza virus
HiB
73
What are the causative organisms of pharyngitis and appropriate treatments
Viral ~66.6%
S. pyo ~33.3% => Amoxicillin
74
What is the pathogenesis of asthma
Increase Th2 activation => IL4 activates B cells & IL5 activates Eosinophils
Mast cells activated by B cells (IgE) and Eosinophils => release histamine, PG and LTB4/D4 => Bind to LTR => Bronchoconstriction, Increase permeability (oedema), Increase mucus secretion by goblet cells that obstruct airway
In late phase, Eosinophils release MBP and cationic proteins that cause epithelium damage
75
What is non-atopic asthma
Hypersensitive airways triggered by irritants eg smoke
76
What are the pathologies of asthma
Hyperactivity, Hypertrophy of bronchus SM
Hypersecretion of mucus
Mucosal oedema
Infiltration of bronchus mucosa by eosinophils, mast cells and macrophages
77
Compare between acute and chronic asthma
Acute
- Inflammation and bronchoconstriction
Chronic
- SM hyperplasia
- Airway remodelling
- Goblet cell metaplasia
- Mucus overproduction
78
Compare between allergic and eosinophilic asthma
Allergic
- Type 1 hypersensitivity
- IgE mediated
- IL4, 13
Eosinophilic
- Type 2 hypersensitivity
- Cell mediated
- IL4, 5, 13
80
What is the pathogenesis of COPD bronchitis
Inflammation of bronchi
Luminal narrowing and mucus hyper secretion
Airway obstruction
Alveolar hypoventilation
Hypoxic vasoconstriction to redirect blood to other alveoli
Increase Pul arterial pressure
RHF in long term
81
Why is O2 administration not used for COPD bronchitis
Causes vasodilation which diverts blood from well ventilated alveoli => Dead space
Decrease Hb affinity for CO2 => Increase PaCO2
Decrease chemoreceptor stimulation => Decrease min vent
=> CO2 retention
82
Compare brain ecf acidity and ventilatory drive between chronic and acute COPD
Chronic = less acidic brain ecf, less sensitive to increase pCO2
Acute = more acidic brain ecf, more sensitive to increase pCO2
83
What is pathogenesis of emphysema
smoking => A1 anti-tripsin deficiency => decrease inhibition of elastase released by neutrophil/macrophages => breakdown elastin in alveolar walls => loss of elasticity and recoil => trapped inhaled air and exhalation impairment => dilation
84
What is panacinar emphysema
Entire acinus is uniformly affected
85
What are the CXR findings of emphysema
Barrel chested
- Increase anteroposterior diameter of thorax
- Flatted hemidiaphragms
86
Compare the clinical features, PaO2, PaCO2 and progression of bronchitis and emphysema
Clinical features:
Emphysema = Catechic, pursed lip breathing, mild cough
Bronchitis = Productive cough, overweight, oedema
PaO2
Emphysema = slight hypoxia
Bronchitis = markedly hypoxic
PaCO2
Emphysema = normal
Bronchitis = Early hypercapnia
Progression
Emphysema = Type 1 respiratory failure
Bronchitis = Type 2 respiratory failure
87
Compare type 1 and 2 respiratory failure
Type 1
- VQ mismatch = hypoxemia only
- Shunt (pneumonia, pul oedema), Dead space (Pul. embolism)
- Initially correctable w hyperventilation
Type 2
- Poor ventilation = hypoxemia w hypercapnia
- Blocked airways, breathing nm failure
- Address underlying vent failure
88
What is the pathogenesis of Bronchiectasis
Interference w secretions drainage
- Obstruction of proximal airway eg tumour/foreign body
- Abnormality of mucus viscosity eg cystic fibrosis/immobile cilia
Recurrent infection
=> Dilated airways, purulent secretions, chronic wall inflammation, loss of normal epithelium
89
What are the imaging findings of bronchictasis
Dilated bronchi and bronchioles
90
What are the symptoms of bronchiectasis
Cough, Dyspnoea, Foul smelling sputum, Hemoptysis, Clubbing
91
What are the complications of Bronchiectasis
Chronic suppuration => Lung abscess
Hypoxemia => Pul HTN = > RHF
92
Which demographic is prone to obstructive sleep apnoea
Fat people
93
Explain the pathogenesis of Acute Respiratory Distress Syndrome
Trauma/burns/toxic fumes/sepsis release cytokines into blood
Damage to alveolar lining and capillary endothelium
Interstitial oedema => high protein exudation into alveoli + hyaline membranes => hypoxemia and death (70%)
Type 2 pneumocyte regeneration and interstitial inflammation => Interstitial fibrosis
Mild local fibrosis (10%)
Marked interstitial fibrosis (Honeycomb lung) (20%)
94
Describe hyaline membranes
Fibrin-fluid rich + necrotic epithelial cells
Increase thickness => Decrease diffusion of O2 => hypoxemia
95
What is pulmonary fibrosis caused by
Repeated exposure , sensitisation and type IV hypersensitivity
96
What does pulmonary fibrosis lead to
Honeycomb lung
Chronic respiratory impairment => Respiratory/ cardiac failure => death
97
What is the most common cause of hypersensitivity pneumonitis
Animal proteins eg bird droppings
98
What is the pathophysiology of hypersensitivity pneumonitis
Acute exposure => Type III => respiratory symptoms (4-8h)
Chronic exposure => Sensitisation => Type IV => pul. fibrosis
99
What is sarcoidosis
Non-necrotising granulomas in intrathoracic/ hilar lymph nodes
100
What is the most common cause of pneumoconiosis
Abestos (Occupational exposure eg shipyard)
101
What are the complications of pneumoconiosis
Malignant mesothelioma
Lung carcinoma
Lung fibrosis
Pleural plaques/thickening
101
Explain the pathophysiology of MTb primary infection
Inhalation of Tb
Infection @lung peripheries (Ghon's focus)
Conveyed to local lymph nodes @lung hilum
Enlargement through granulomatous inflammation and caseation
102
When does secondary Tb infection occur
Immunocompromised states
103
What are complications of Tb disease
Severe pneumonia
Continuing enlargement of caveating granulomas in lymph nodes
Lymphohematogenous dissemination
- walls of bronchus = Tb bronchopneumonia
- Blood vessels = Miliary Tb
104
What are the CXR findings of miliary Tb
Multiple granulomas in blood
Millet seeds on lung
105
How is Tb screened
Latent
- Mantoux Tb skin test
- IFN G release assay
Active
- Microscopy = Acid fast bacilli; Ziel Nielsen stain
- Sputum samples (3x)
- CXR
106
What are the CXR findings of primary and reactivated Tb
Primary (lower/middle lobe)
- Consolidation
- Hilar lymphadenopathy
- Ghon complex
- Pleural effusion
Reactivated Tb
- Consolidation
- Calcification
- Fibrocaseous cavitory lesions in upper lobes
106
What is the histopathology of Tb
Caseous necrosis
Langhans giant cell
Lymphocytes and macrophages
107
What are the symptoms of Tb
Fever, night sweats, haemoptysis, weight loss, cough
108
What is the treatment for Tb
Rifampicin, Isoniazid, Pyrazinamide, Ethambutol
RIPE 2 months, RI 4 months
108
What are the causative organisms for community acquired pneumonia and appropriate treatments
Typical => Macrolide & Levoflaxacin
- S pneumo (m/c)
- HiB
- Moraxella
- MRSA
Atypical => Macrolide/ Amoxicillin for bacterial
- RSV (m/c children)
- Influenza/covid (m/c elderly)
- Mycoplasma
- Chlamydophila
- Legionella
109
What are the causative organisms for hospital acquired pneumonia and treatments
Gram neg = PAE, Ecoli, Kleb => Pip-tazo
MRSA => Vancomycin
109
What are the causative organisms for immunosuppressed pneumonia
Jivorecci, Tb, CMV, Asperlligus and candida
110
What are the causative organisms for aspiration pneumonia
Oral anaerobes + Aerobes eg MRSA, S.pneumo, PAE
110
Describe bronchopneumonia
Patchy consolidation on lower lobes
Productive cough w purulent sputum, dyspnoea
111
Describe lobarpneumonia
Consolidation of whole/part of lobe
S.pyo and kleb => infect alveolar spaces
Inflammation: Congestion (D1-2) => Red heaptization (D3-4) => Grey hepatization (D5-7) => Resolution (D8-w4)
112
Describe atypical pneumonia
Inflammation confined to alveolar septa and lung
Interstitium no alveolar exudation
113
What are the CXR findings of pleural effusion
Blunting of costophrenic angle
114
Compare transudative and exudative pleural effusion
Transudate
- Low protein fluid caused by starlings forces eg cirrhosis, HF
Exudate
- High protein fluid caused by inflammation eg infection, malignancy
115
What is spontaneous pneumothorax
Bleb/ bullae rupture => Air enters pleural space, pleural P increase => Lung compressed and collapses
Thin young men and asthmatics
116
What is traumatic pneumothorax
Penetrating trauma => air entry through chest wall lesion
Blunt trauma => air entry through hole in lung
117
What is tension pneumothorax
1 way valve system => air enters from surrounding upon inspiration but cannot exit
Collapse of ipsilateral lung => compress contralateral lung, trachea, heart & SVC
Decrease venous return , CO, respiratory function
117
What are the pathologies of pleurisy
Fibrinous/ purulent exudate on pleural surface => organise to form fibrous pleural adhesions
Bacterial = neutrophils
Tb = lymphocytic
118
Who has the highest risk of getting small cell carcinoma
Smokers
119
What are the features of small cell carcinoma
Hilar, central masses, rapid growth rate
Extensive necrosis
Tumour w neuroendocrine differentiation
Wide metastasis, aggressive, poor prognosis, many paraneoplastic syndromes
120
What are the histological features of small cell carcinoma
Small neoplastic cells
Scant cytoplasm w ill-defined cell borders
Finely granular nuclear chromatin
121
What are the non-small cell carcinomas
Adenocarcinoma and squamous cell carcinoma
122
Which demographic is at risk of lung adenocarcinoma
Female non-smokers
123
What are the features of lung adenocarcinoma
Peripherally located
Presence of glandular differentiation
EGFR mutation => constitutive activation
Good prognosis and well differentiated
123
Which demographic is at risk of lung squamous cell carcinoma and describe the features
Male smokers
Squamous metaplasia/dysplasia => central cavitation and necrosis
Locally invasive, rapid growing
Keratin pearls
124
What are paraneoplastic syndromes often caused by
Endocrine disturbances
124
What are some paraneoplastic syndromes
SIADH => Excessive ADH production => Increase VSP secretion => More water than salt retention
Horner's syndrome = Miosis, ptosis, apparent anhidrosis
SVC syndrome = Tumour blocks SVC => systemic backpressure => distended neck veins and oedema
124
What are the complications of lung cancers
Tumour spread into pleura => Pleural effusion
Recurrent laryngeal nerve invasion => Hoarseness
Phrenic nerve invasion => Diaphragm paralysis
Pericardial = Pericarditis/ Cardiac tamponade
125
What is thymoma
Neoplasm derived from thymus epithelial cells a/w myasthenia gravis
126
What is the most common thymus neoplasm in children
Lymphoma
127
What is the pathophysiology of Cor Pulmonale
Obstruction of lung blood flow => right heart back pressure => Increase right heart contractility => RHF
128
What disease can cause Cor Pulmonale
COPD
129
What are the complications of Pulmonary arterial hypertension
Medial hypertrophy of arteries => occlusion => further increase pressure
130
What are the causative organisms for ear infections
Otitis media
- S. pneumo (#1)/ H. inf => Amoxicillin/ Co-amoxiclav
- Viral
Malignant otitis externa
- PAE => Pip tazo (IV)
131
What are the causative organisms and treatment of Epiglottitis
H. inf/ S.pneumo => Ceftriaxone (IV)
