Respiratory l Flashcards
1
Q
casue of Acute rhinitis
A
Aka the common cold, it is caused by allergies or A viral infection (adenoviruses)
2
Q
Clinical picture of Acute rhinitis
A
1) runny nose
2)sneezing
3) nasal congestions
4) mild soar throat
3
Q
Pathogenesis of allergic rhinitis
A
*IgE immune l reaction
*association with mucosal and submucosal mast cells
*increase in Eosinophils in peripheral blood and nasal discharge
4
Q
Bacteria causing bacterial infection of acute rhinitis
A
Staphylococci, streptococci, H.Influenza
5
Q
*fibrous scarring
*atrophy of the epithelium and mucous glands
* decreases vascularity
Are the micro-/macroscopic features of what respiratory condition?
A
Acute rhinitis caused by bacterial infection
6
Q
__________ is a common condition characterised by inflammation and swelling of the sinuses for at least 12 weeks, despite treatment attempts
A
Chronic sinusitis, aka chronic rhinosinusitis
7
Q
Epidemiology of chronic sinusitis
A
Young and middle-aged adults
8
Q
Cause of chronic sinusitis
A
- Infection or
- nasal polyps in the sinusis, or
- deviated nasal septum
9
Q
Pathogenesis of chronic sinusitis
A
Obstruction of drainage outlets from the sinuses —> accumulation of mucous secretions or exudate
10
Q
Signs and symptoms of chronic sinusitis
A
1)thick discoloured discharge from the nose
2) nasal obstruction congestion (nasal inflammation)
3) pains tenderness and swelling around the eyes, cheeks, nose/forehead
4) reduced sense of smell and taste(adults), cough (children)
Other sings and symptoms:
1)fatigue
2)ear pain
3) aching in the upper jaw and teeth
4)sore throat
5)bad breath
6)Nausea
7) cough that might worsen at night
11
Q
State the difference between Acute vs chronic sinusitis
A
*similar signs and symptoms
However, fever is a common sign of acute sinusitis but not chronic sinusitis
Acute sinusitis: a temporary infection of the sinuses, often associated with a cold
Chronic sinusitis: the signs and symptoms often last longer and cause more fatigue
12
Q
————— acute inflammation of the larynx
A
Laryngitis
13
Q
Cause of laryngitis
A
Inhalations of irritants, allergic reactions, bacteria, viruses, voice overuse
14
Q
Clinical manifestations of laryngitis
A
Hoarseness—-> due to inflammation and Oedema of the vocal cords
15
Q
What are the 2 uncommon forms of laryngitis?
A
1) tuberculous laryngitis ( caused by active Tbc; infected sputum is coughed up)
2) diphtheritic laryngitis
16
Q
Pathogenesis of diphtheritic Laryngitis : Inhalation of ——————- —>implantation on the upper-airways’ mucosa—> release of exotoxin —> necrosis of the epithelium—> dense fibrino-purulent exudate
A
Corynebacterium diphtheriae
17
Q
Clinical features of Diphtheritic Laryngitis
A
tonsils and pahrynx:
–> sore throat, low fever, malaise (restlessness), dysphagia
–> “Bull neck” (p.18) due to swelling and inflammation of the lymph nodes (lymphadenopathy)
larynx:
–> Hoarsness (loss of voice/ sever respiratory tract obstruction)
skin:
pain, tenderness and erythema —> ulcers with sharply defined borders and browinish-grey membrane (see p.20)
18
Q
Complications of Diphtheritic Laryngitis
A
1) Myocarditis and peripheral neuropathy –> absorption of bacterial exotoxins
2) obstruction of major airways –> sloughing and aspiration of pseudo-membrane
19
Q
——–: Acute inflammation of the epiglottis
A
Acute Epiglottits
20
Q
Epidemiology of Acute Epiglottitis
A
young children
21
Q
Cause of Acute Epiglottitis
A
Haemophilus influenzae (H. influenzae)
22
Q
clinical features of Acute Epiglottits
A
pain and airway obstruction
23
Q
prognosis of Acute Epiglottitis
A
Failure to appreciate the need to maintain
an open airway for a child → Life-threatening
condition with fatal consequences
24
Q
Croup?
A
Aka Acute Laryngotracheobronchitis
–> inflammation of the larynx, trachea and epiglottis
25
casue (virus) of Croup in children
1) Parainfluenza Virus (most common)
2) Respiratory Syncytial Virus
26
clinical picture of Croup
- Harsh, persistent cough
- Inspiratory stridor (noisy high-pitched sound with breathing, caused by blockage or narrowing in the upper airway)
-restlessness
- increased respiratory rate
- supra-sternal retraction
27
Complications of Croup
* Occasionally, laryngeal inflammatory reaction →Prominent airway narrowing → Respiratory failure
* Secondary bacterial infection (Staphylococci, Streptococci, H. influenzae) of upper respiratory tract
28
--------------: Nosebleed, which can range from a trickle to a strong flow
Epistaxis
29
The 2 types of Epistaxis
1) Anterior (most common) : originates in the Kiesselbach's plexus (vessels in the antero-inferior septum)
2) posterior [less common, but more serious]; Associated with atherosclerosis or bleeding disorders
--> (originates in the posterior septum overlying the vomer bone, or laterally on the inferior or middle turbinate)
p.26
30
cause of Epistaxis
1) drying of nasal mucosa
2) local trauma (casued by nose picking or blowing)
3) less common: coagulopathy, arteriosclerosis, local infections, foreign bodies, septal perforation
31
What are the signs of Epistaxis that must be given particular attention for?
1) bleeding not stopped by direct pressure
2) Use of anticoagulant drugs
3) miltiple recurrences, with no clear cause
4) signs of Hypovolemia (loss of body fluid) and heamorrhagic shock
5) cutaneous signs of a bleeding disorder
32
-------------- : Tissue injury caused by a pressure related change in body compartment gas volume
Barotruama
33
Affected organs in Barotrauma
lungs, ears, sinusis, GI tract, etc.
34
risk factors of Barotrauma
(those interfering with eq. of pressure)
1) sinus congestions
2) infection
3) Eustachian tube blockage
4) structural anomaly
35
pathogenesis of Barotrauma
Entrapment of air or other gas within
the lungs → Over-inflation of them → Pulmonary barotrauma
36
Symptoms of Barotruama
1) ear pain
2) hearing loss
3) sinus pain
4) vertigo
5) abdominal pain
6) alveolar rupture and pneumothorax (collapsed lungs) --> Dyspnoea and loss of consciousness
7) Epistaxis
37
diagnosis of Barotrauma
Clinical evaluation
Imaging tests
38
treatment of Barotrauma
case 1 : life threatening conditions like Alveolar and GI rupture
a. Abnormal vital signs --> high flow 100% O2
b. respiratory failure --> endotracheal intubation
case 2: Nurologic symptoms:
--> recompression chamber
case 3: pneumothorax
--> chest decompression with a large bore needle ( 2nd intercostal space, mid-clavicular line) and subsequent thoracostomy
39
Laryngeal/Pharyngeal Obstruction: Blockage of upper airway, occurs when the (upper/lower ?) breathing passages become ------------- or ------------ → Impairment of breathing
upper, narrowed, blocked
40
parts affected as a result of Laryngeal/Pharyngeal Obstruction
trachea, larynx and pharynx
41
causes of laryngeal/pharyngeal obstruction
1) allergic reactions to various agents and substances
2) fire or burns from breathing in smoke
3) chemical burns and reactions
4) Epiglottitis
5) injury or infection of the upper airways
6) laryngeal cancer
7) peritonsillar or retropharyngeal abscess
42
symptoms of Laryngeal/Pharyngeal Obstruction
1) choking
2) unusual breathing sounds: wheesing, Crowing, whistling
3) loss of consciousness
4) confusion and panic
5) Cyanosis
6) difficulty in breathing and gasping air
7) agitation or fidgeting
43
exams and tests for Laryngeal/Pharyngeal Obstruction
*X-ray
*bronchoscopy
*laryngoscopy
physical examination:
--> decreased breath sounds in the lungs
--> Rapid, shallow, or slowed breathing
44
treatment for Laryngeal/Pharyngeal Obstruction
1) endotracheal intubation
2) Tracheostomy or cricothyrotomy (p.39)
3) removal of stacked objects with special instruments
45
Inhalation of a foreign object into the nose, mouth, or lower respiratory tract → Stuck within the respiratory system → Breathing problems or choking caused by →
------------------ and -----------------
Inflammation and infection
46
epidemiology of inhalation of Forgein body
Mostly children, 1-3 years old
47
causes of forgein body related conditions
Certain foods (e.g. nuts, seeds, popcorn) and
small objects (e.g. buttons, beads) → Partial or total airway blockage
48
symptoms of inhalation of a foreign body
* Patients with complete airway obstruction require immediate medical attention and typically are aphonic (loss of voice) and unable to breath
*Patients who are coughing, gagging, and vocalising have partial obstruction
49
management of inhalation of a foreign body
Use of the Heimlich manoeuvre has improved the mortality rate of patients with complete airway obstruction, but use of it in patients with partial obstruction may produce complete obstruction
50
epidemiology of nasal Papilloma
* Most common benign neoplasm of nasal cavity and paranasal sinuses
* Male, 50-60 years
51
clinical features of nasal papilloma
1) nasal obstruction
2) Epistaxis
52
what are the 2 types of nasal papilloma
1) Exophytic: Grows outward from epithelial surface; Lateral walls
2) Endophytic: Grows inward into tissues in finger-likeprojections from a superficial site of origin; Nasaldiaphragm
53
*Cylindrical epithelium of airway tract with increase in the number of cellular rows
*Squamous metaplasia of cylindrical epithelium
*Resemblance to transitional (cell) epithelium
Are the microscopic features of what nasal carcinoma?
nasal papilloma
54
epidemiology of nasal angiofibroma
Rare, prominent vascularised lesion
55
clinical manifestaions of nasal angiofibroma
Mainly with epistaxis
56
localisation of nasal angiofibroma
In the posterior nasal wall of adolescent
males
57
microscopic findings of nasal Angiofibroma
Numerous blood vessels in a marked fibrotic matrix
58
prognosis of nasal Angiofibroma
Histologically benign, but locally aggressive
59
epidemiology of nasal Squamous cell Carcinoma
Most frequent malignant nasal tumour
*All types of differentiation (well-, moderately- and poorly-differentiated tumours)
60
* Large, eosinophilic and polygonal cells
* Cells are layered in an architectural pattern that looks like squamous cell epithelium
*Frequently, keratin production (in the centre of agroup of epithelial cells with a whorled appearance;This type of keratin is known as “keratin pearl”)
Are the microscopic feature of which nasal carcinoma?
squamous cell carcinoma
61
undifferentiated Nasopharyngeal Carcinoma is aka?
Lymphoepithelioma
62
epidemiology of Nasopharyngeal Carcinoma
Common in Southeast Asia and
East Africa
63
cause of Nasopharyngeal Carcinoma
Epstein-Barr virus
64
localisation of nasopharyngeal carcinoma
Pharyngeal fossa of Rosenmülle
65
*Tumours composed of sheets or large bands of large undifferentiated cells that also contain a population of non-neoplastic small (predominantly T) lymphocytes
* Tumour cells with vesicular nuclei and prominent cytoplasm
*No signs of keratinisation
Are the microscopic features of which Carcinoma?
Nasopharyngeal Carcinoma
66
Epidemiology of Nasal Adenocarcinoma
5% of malignant tumours of the nose
and throat
67
* Intestinal-Type Adenocarcinoma (Neoplastic
intestinal glands resembling Colonic Adeno-Ca)
* Non-Intestinal Type Adenocarcinoma
* Salivary gland-like Carcinomas (Adenoid Cystic Carcinoma)
Are the microscopic classifications of which Nasal Carcinoma?
Adenocarcinoma
68
Olfactory Neuroblastoma is aka?
Aesthesioneuroblastoma
69
epidemiology of Olfactory Neuroblastoma
Usually, older male patients (paediatric tumours:
adrenals/abdomen of infants and young children)
70
*Small round blue cells in a neurofibrillary matrix
*Characteristic Flexner-Wintersteiner rosettes
Are the microscopic features of which carcinoma?
Olfactory Neuroblastoma
71
Immunohistochemistry of nasopharyngeal carcinoma
[+] PANCKs, CK-8, -18, -19, ΕΜΑ, B-, T-cell, LCA and EBV (EBER in-situ hybridisation)
72
immunohistochemistry of Olfactory Neuroblastoma
Positivity for: Chromogranin,
ACTH, Neurofilament (NF), Neuron Specific Enolase(NSE), S-100 and Cytokeratins (CKs)
73
localisation of nasal (extramedullary) Plasmacytoma
Upper airway tract --> Most common
extra-medullary site
*Either as a regional manifestation of Multiple
Myeloma or as a primary lesion
74
*Sub-mucosal localisation
*Airway tract obstruction
*Ulceration and haemorrhage
Are the macroscopic features of which nasal carcinoma?
Extramedullary Plasmacytoma
75
*Diffuse cellular population
*Round to ovoid cells
*“Cart-wheel” chromatin
*Basophilic cytoplasm
Are the microscopic findings of which nasal carcinoma?
extramedullary Plasmacytoma
76
immunohistochemistry of Extramedullary Plasmacytoma
--> Positivity in one of the light
chains (κ, λ) and in one
immunoglobulin (IgG, IgM)
-->Positive staining for: CD38,
CD79A, CD138, VS38c
77
--------------- : Aggressive mesenchymal malignancy of skeletal muscle origin
Embryonal Rhabdomyosarcoma
78
epidemiology of Embryonal Rhabdomyosarcoma
* Most common soft tissue sarcoma of childhood and adolescence
* Approximately 87% of patients <15 years
79
localisation of Embryonal Rhabdomyosarcoma
Occurrence in any anatomic site, although
mostly in the head, neck or genitourinary tract
80
* Small, round blue cell tumour
* Cells with high cytologic variability (representing several stages of skeletal muscle morphogenesis):
* Appearance of highly differentiated
neoplasms containing rhabdomyoblasts
with large amounts of eosinophilic
cytoplasm and cross striations, or
* More commonly, the appearance of poorly
differentiated tumour cells
*Elongated pleomorphic tumour cells
*Centrally located hyperchromatic nuclei
* Variable nuclear pleomorphism
* Loose, myxoid or cellular collagenous stroma
* High mitotic index
*Prominent nucleoli
Are the microscopic features of which Nasal Carcinoma?
Embryonal RHabdomyosarcoma
81
clinical features of Embryonal Rhabdomyosarcoma
*Expanding mass → Pain and symptoms related to the compression of nearby structures
*Metastases
→ Pain in the bones
→ Anaemia, thrombocytopenia, and
neutropenia
→ Difficulty with respiration due to lung
nodules or pleural effusion
82
prognosis of Embryonal Rhabdomyosarcoma
*Metastatic tumours: 5-year survival rate less
than 30%
* Confined disease treated with combined
surgery, radiation and chemotherapy: 5-year
survival rate of over 80%
83
pathogensis of squamous cell carcinoma of the Oropharynx
--> Association with high risk HPV (Type 16, ~80% of cases)
--> Most frequent tumour in this location (mainly in palatine and lingual tonsils)
84
histopathology of squamous cell carcinoma of the Oropharynx : (Non-kretanising/kreatinising) squamous cell carcinoma with -------------- morphology
Non-Kreatinsing, Basaloid (p. 84)
85
epidemiology of squamous cell carcinoma of the oropharynx related to HPV(+) cases
*young patients
*Non-smokers
*higher stage at presentation, with cervical lymph nodal metastases
*better prognosis than HPV(-) cases [association wiht tobacco and alcohol abuse)
86
what are tumours of the larynx ka?
Vocal Cord Nodule or Singer’s Nodule
87
cause of vocal cord nodule tumours
1) Chronic irritation (e.g. excessive use
of the voice)
2) heavy cigarette smoking
88
vocal cord nodule tumors are localised to the [TURE/FALSE?] vocal cords?
TRUE vocal cords
89
Epidemiology of squamous papilloma of the larynx
* Benign neoplasm; Rarely becomes malignant
* Association with low-risk HPV-6 and -11
*Centered around true vocal cords
*Multiple lesions (in children and adolescents) → Extension into the trachea and bronchi → Airway obstruction [Juvenile laryngeal papillomatosis]
90
epidemiology of squamous cell carcinoma of the larynx
*Most common malignant tumour of the larynx
*Men >40 years
91
predisposing factors of squamous cell carcinoma of the larynx
* Combination of cigarette smoking and alcoholism
* NO association to HPV infection
92
clinical picture of squamous cell carcinoma of the larynx
Persistent hoarseness
93
Epidemiology of Glottic Carcinoma
--> carcinoma in the larynx
--> originates from the true vocal cords
--> most common and best prognosis
94
epidemiology of supra- and subglottic carcinomas (of the larynx)
less common and worse prognosis (compared to glottic carcinoma )
95
give exmaples of Infectious, Immunologic and Inflammatory Disorders of the Upper Airways:
Acute Rhinitis
Sinusitis (Acute and Chronic)
Laryngitis (e.g. viral, bacterial, diphtheritic)
Acute Epiglottitis
Acute Laryngotracheobronchitis (Croup)
96
list a few Traumatic and Mechanical Disorders of the Upper Airways:
Epistaxis
Barotrauma
Laryngeal/Pharyngeal Obstruction
Tracheomalacia
Foreign Body
97
------------------ : Lesions of congenital origin derived from the primitive foregut
Bronchogenic Cysts
98
Epidemiology of Bronchogenic cysts
--> most common primary cysts of the mediastinum
--> Majority of the cysts are in the mediastinum
the rest --> lung parenchyma :15-20%
99
describe what is observed in an imaging study of Bronchogenic cysts
--> uni-locular, non-calcified masses
--> sphearical or oval, with smooth outlines
100
(DD) Differential Diagnosis of Bronchogenic cysts
Lung abscess, Tbc, infected bullas, neoplasms, etc.
101
macroscopic features:
* Uni-locular cyst (cyst with a single sac)
* Content: Clear fluid, haemorrhagic secretions or air
Are the features of what respiratory condition?
Bronchogenic cysts
102
microscopic features
* Cyst’s internal lining: Columnar ciliated epithelium
* Cyst’s wall: Cartilage and bronchial mucous glands
Bronchogenic cysts
103
clinical features of bronchogenic cysts
* Cough
* Fever
* Pain
* Dyspnoea
* Tracheobronchial compression and lung infections (in children; because of the soft tracheo-bronchial tree)
104
complications of Bronchogenic cysts
* Infections (in cysts with bronchial communications)
* Rapture of cyst into trachea, pleural or pericardial cavity
* Pneumothorax, accompanied by pleuritis
105
what are the 2 Most common congenital malformations of the lower respiratory tract?
* Congenital Cystic Adenomatoid Malformation [CCAM]
(= congenital pulmonary airway malformation)
* Broncho-Pulmonary Sequestration [BPS]
106
localization of Broncho-Pulmonary Sequestation
1) Intralobar:
-->Observed within the lung
-->Without own pleura
2) Extralobar:
--> Completely covered with pleura
-->May be extrathoracic; 10% subdiaphragmatic, left side
3) Both intra- and extralobar:
--> Solid, well-circumscribed and echogenic masses (US), similar to Type 3 CCAM (Bronchial/alveolar)
107
types of congenital Diaphragmatic Hernia
1. Postero-lateral Bochdalek-type (70%)
2. Anterior Morgagni-type (27%)
3. Central septum transversum-type (2-3%)
* CDH defects range from small subcentimeter defects to complete diaphragmatic agenesis
* Bochdalek hernias: Left side (85%); Right side (13%); Bilateral (2%)
108
Pathogenesis of CCAM & BPS
* Abnormalities that occur during the branching and proliferation of the bronchial structures
* Abnormal proliferation of tissues, airway obstruction, dysplasia and metaplasia of the normal tissue
109
Congenital Cystic Adenomatoid Malformation [CCAM] classification, based on presumed site of development of the malformation:
0 = Tracheo-bronchial
1 = Bronchial/bronchiolar
2 = Bronchiolar
3 = Bronchiolar/alveolar
4 = Distal acinar
110
Pathogenesis of Congenital Diaphragmatic Hernia
1. Result from a non-fusion of different parts of the diaphragm (failed fusion) → Herniation of
abdominal contents into the thorax →
Compression and dysgenesis of the lungs
2. Abnormal lung development → Results in
abnormal diaphragmatic development
3. Failure of the pleuro-peritoneal fold to fuse with the post-hepatic mesenchyme
111
Diagnosis of Congenital Diaphragmatic Hernia
1) Ultrasound:
--> Assessment of the extent of herniation and
associated mediastinal shift
--> Inadequate to identify a herniated liver because of its comparable echogenicity to the fetal lung
-->Doppler US: Assessment of blood flow to the ipsilateral lung, which closely parallels lung development
2) MRI:
--> Provides detail of the herniated viscera
--> Allows for precise measurements for prognostic calculation
112
What are the 2 factors that determineine the severity of CDH?
1) liver position:
--> Foetuses with the liver up in the chest --> More severe form of CDH and lower survival rate
2) Lung-to-Head Ratio or LHR:
--> Numeric estimate of the size of the foetal lungs, based on measurement of the amount of visible lung; High LHR values >1.0 --> Better outcomes
*LHR: luteinizing hormone receptor
113
Immotile Cilia Syndrome is aka?
Primary Ciliary Dyskinesia, Kartagener Syn.
114
Cause of Immotile cilia syn.
Mutations in the:
1) DNAI1 [Dynein Axonemal Intermediate chain1] &
2) DNAH5 [Dynein Axonemal Heavy
chain 5] --> 30% of cases; Autosomal recessive
inheritance
115
Immotile cilia syn is charcterised by:
a. Chronic respiratory tract infections
b. Abnormally positioned internal organs
c. Infertility
116
Signs and symptoms caused by immotile cilia syn.?
1) Babies--> Breathing problems at birth
2) Early childhood --> Frequent respiratory tract infections → Bronchiectasis
3) 50% of patients--> Situs inversus totalis (mirror-image reversus)
4) 12% of patients --> Heterotaxy syndrome or situs ambiguus --> Structurally abnormal or improperly positioned organs (heart, liver, intestines, spleen).
- May also be accompanied by asplenia or polysplenia
5) Infertility (males: due to flagella dysfunction of sperms; females: due to abnormal cilia in the
fallopian tubes)
117
Treatment of Abnormal cilia syndrome
1) Antibiotics --> Infections (caused commonly by Hemophilus influenzae or Staphylococcus aureus)
2) Inhaled bronchodilators, mucolytics, and chest physiotherapy --> Obstructive lung disease/ bronchiectasis
3) Surgical care: Tympanostomy tubes → Reduction of recurrent infections and conductive hearing loss
118
causes of pulmonary embolisim
1) Venous thrombosis (lower extermities or pelvis)
2) fat
3) amniotic fluid
4) clumps of tumour cells or bone marrow
119
Risk factors of Pulmonary embolism
1) Stasis of blood flow (prolonged bed rest or immobilisation)
2) Hypercoagulable states
3) Use of Oral contraceptives
120
clinical findings of Pulmonary embolism
1) Saddle embolus:
*A sudden increase in Pulmonary Artery pressure
*Acute right ventricular strain → Sudden death
2) Pulmonary infarction:
*Sudden onset of dyspnoea and tachypnoea
*Pleuritic chest pain
*Friction rub
*Effusion
*Expiratory wheezing
121
laboratory findings of Pulmonary embolism
1) Respiratory alkalosis (arterial PCO2 <33 mmHg)
2) PaO2 <80 mmHg (90% of cases)
3) Increase in A(lveolar)-a(rterial) gradient (100% of cases)
4) Increase in D-dimers
5) Positive D-dimers
* Good sensitivity (85-98%)
* Poor specificity
122
Diagnostic tests of Pulmonary embolism
1) Chest X-ray
-->Elevation of ipsilateral hemi-diaphragm
-->Pleural effusion (haemorrhagic)
-->Westermark’s sign of peripheral oligaemia
-->Fleischner’s sign of “amputated” pulmonary artery
--> Hampton hump (wedge-shaped area of
consolidation)
2) Abnormal Perfusion Radionuclide Scan
-->Ventilation scan: Normal
-->Perfusion scan: Abnormal
-->Pulmonary angiogram: Gold standard
confirmatory test
123
* Red-blue raised wedge-shaped area that extends to the pleural surface
* Majority are located in the lower lobes (Perfusion > Ventilation)
*Fibrinous exudate on pleural surface
*Haemorrhagic pleural effusion
Are the macro-/micro scopic features of what kind of embolism?
Pulmonary embolism
124
Epidemiology of primary pulmonary hypertension
* Rare with Unknown aetiology; Genetic predisposition
* NO heart or lung disease
* Vascular hyper-reactivity with smooth muscle proliferation
125
Hisologic picture of primary pulmonary hypertension
Characteristic plexiform lesions
126
Epi of secondary pulmonary hypertension
More common than primary
127
pathogenesis of Secondary pulmonary hypertension
* Endothelial cell dysfunction
-->Loss of vasodilators (e.g. NO)
--> Increase in vasoconstrictors (e.g. Endothelin)
*Hypoxaemia & Respiratory Acidosis → Pulmonary arteries vasoconstriction → Smooth muscle
hyperplasia and hypertrophy
128
causes of secondary pulmonary hypertension
1) Chronic hypoxaemia (e.g. Chronic lung disease)
2) Chronic respiratory acidosis (e.g. Chronic bronchitis)
3) Loss of pulmonary vasculature → Workload for remaining vessels (e.g. Emphysema, recurrent pulmonary emboli)
4) Left-to-right cardiac shunts → Volume overloading pulmonary vasculature
5) Left-sided valvular disease (e.g. Mitral stenosis) → Backup of blood into pulmonary veins → Venous hypertension
129
Histopathology
1) Atherosclerotic changes of main pulmonary arteries (Result of ↑ pressure to endothelium → Endothelial injury)
2) proliferation of myo- intimal and smooth muscle cells
Are the features of what condition?
Secondary Pulmonary Hypertension
130
pathogenesis of pulmonary oedema
1. Due to alterations in Starling forces (transudate)
* Increased hydrostatic pressure in pulmonary
capillaries
-->Left-sided heart failure
-->Volume overload
--> Mitral stenosis
*Decreased oncotic pressure
—>Nephrotic syndrome
—>Cirrhosis
2. Due to micro-vascular or alveolar injury (exudate) --> Increased alveolar capillary permeability
▪ Infections (e.g. sepsis, pneumonia)
▪ Aspiration (e.g. drowning, gastric contents)
▪ Drugs (e.g. heroin)
▪ High altitude
▪ Acute Respiratory Distress Syndrome (ARDS)
131
causes of Adult Respiratory Distress Syndrome
(ARDS)
Shock, sepsis, trauma, uraemia, aspiration of
gastric contents, acute pancreatitis, inhalation of chemical irritants, oxygen toxicity, heroin, bleomycin, etc
132
pathogenesis of Adult Respiratory Distress Syndrome (ARDS)
Damage to alveolar capillary endothelium and alveolar epithelium (Diffuse alveolar damage) → ↑ in alveolar capillary permeability → Leakage of protein-rich fluid into alveoli
133
pathogenic factors of Adult Respiratory Distress Syndrome?
* Neutrophils → Release of substances, toxic to
alveolar wall
* Activation of coagulation cascade → Micro-emboli
* Oxygen-derived free radicals → Oxygen toxicity
134
clinical features of Adult Respiratory Distress Syndrome (ARDS)
Impairment of respiratory gas exchange → Severe hypoxia
135
Histopathologic pictures of Adult Respiratory Distress Syndrome (ARDS)
Formation of intra-alveolar hyaline membranes (fibrin and cellular debris)
136
cause of Neonatal Respiratory
Distress Syndrome (NRDS)
Deficiency of surfactant, due to immaturity
137
clinical features of Neonatal Respiratory
Distress Syndrome (NRDS)
1) Dyspnoea
2) Cyanosis
3) Tachypnoea
138
what are the advantages of surfactants in Neonatal Respiratory Distress Syndrome? where are they secreted from ?
1) Reduces surface tension within the lung →
Facilitates expansion during inspiration and
prevents atelectasis during expiration
2) Secreted by type II pneumocytes
138
predisposing factors of Neonatal Respiratory
Distress Syndrome (NRDS)
1) Prematurity
2) Maternal Diabetes Mellitus
3) Birth by caesarian section
138
Macro-/Microscopic findings:
*Heavy lungs, with alternating areas of atelectasis and alveolar or alveolar-ductal dilatation
*Engorgement of small pulmonary vessels
*Leakage of blood products into the alveoli →
Formation of intra-alveolar hyaline membranes
(fibrin and cellular debris)
Are the features of what respiratory syndrome?
Neonatal Respiratory Distress Syndrome (NRDS)
139
complications of Neonatal Respiratory
Distress Syndrome (NRDS)
1) Broncho-Pulmonary Dysplasia: Result of treatment with high-concentration oxygen and mechanical ventilation
2) Patent ductus arteriosus: Due to immaturity and hypoxia
3) Intra-ventricular brain haemorrhage
4) Necrotising Enterocolitis: Fulminant inflammation of the small and large intestines
140
❖ Interstitial fibrosis
❖ Inadequate alveolar development
Are the Histopathologic features of which respiratory syndrome ?
Broncho-Pulmonary Dysplasia
141
------------- :Collapse of previously inflated lung, producing areas of relatively airless pulmonary parenchyma
Acquired Atelectasis
142
Acquired atelectasis, divided into:
1) Resorption (or Obstruction) Atelectasis
2) Compression Atelectasis
3) Contraction Atelectasis
