Respiratory Flashcards
Difference btw obstructive and restrictive diseases
Obstructive diseases are characterised by increase in the resistance to airflow oweing to partial or complete obstruction at any level from trachea and large bronchi to terminal and respiratory bronchioles
Restrictive diseases are characterized by reduced expansion of lung parenchyma with decreased total lung capacity
Obstructive diseases:
Emphysema
Asthma
Bronchiectasis
Chronic bronchitis
Restrictive diseases
1. Chest wall disorders like
Polio
Severe obesity
Kuphoscoliosis
Pleural disease
2. Acute or chronic interstetial or infiltrative disease like
ARDS
Dust disease
Interstetial fibrosis of unknown eitiology
Obstructive diseases has decreased fev1 <0.7 L
Restrictive diseases total lung capacity decreases
Expiratory flow rate is normal
Copd
A common preventable and treatable disease that is characterised by persistant respiratory symptoms and airflow limitation that is due to airway or alveolar abnormalities caused by exposure to noxious particles or gases
It consists of
enphysema
Asthma
Bronchiectasis
Chr bronchitis
Emphysema
It is a chronic obstructive airway disease characterised by irreversible enlargement of the air spaces distal to the terminal bronchiole accompanied by destruction of their walls without obvious fibrosis
Types of emphysema
Acc to anatomical distribution
1. Centriacinar
2.panacinar
3.distal or paraseptal
4.irregular
5.others
Centriacinar
Central or proximal part of acini formed by respiratory bronchioles are affected distal alveoli are spared both emphysematous and normal air spaces exist within same acini and lobule.
site :commonly seen in upper lobes particularly apical segments.
occurs predominantly in heavy smokers often in association with chronic bronchitis
Panacinar
Acini are uniformly enlarged from the level of the respiratory bronchioles to THE terminal blind Alveoli.
site:
lower zone
anterior margin of the lung associated with :alpha1 anti tripsin deficiency
Distal acinar
Proximal portion of the acini is normal but the distal part is predominantly involved.
site :along the lobular connective tissue septae, margins of lobules
areas of fibrosis, scarring or atelactasis.
more severe in upper half of the lung
cause: spontaneous pneumothorax
Irregular
Airspace enlargement with fibrosis
Acini are irregularly involved
Invariably associated with scarring.
Pathogenesis of emphysema
It is related to cigarette smoking
And a1 antitrypsin deficiency
Mechanism related to these two factors
1.toxic injury and inflammation
Inhaled smoke causes damage to the respiratory tract epithelium and inflammation. the resident epithelial cells and mq release inflammatory mediators
LTB4
IL8
TNF
chemo tactic agents.
chronic information also leads to accumulation of T and B lymphocytes in the affected lung
2.protease antiprotease imbalance
Alveolar wall destruction resulting from an imbalance between protease and antiprotease mechanism in lung.
genetic deficiency of protease inhibitor alpha 1 anti tripsin has a marked enhanced tendency to develop pulmonary emphysema which is compounded by smoking
3.oxidative stress
Substance in tobacco smoke alveolar wall damage and inflammatory cells release oxidants leading to
tissue damage
endothelial cell dysfunction
inflammation
4. Infection
Bacterial or viral inf may exasberate existing disease
Chronic bronchitis
It is defined as persistent cough with sputum production for atleast 3 months in atleast 2 consecutive years in the absence of any other identifyable cause
Bronchiactasis
It is a disease or disorder characterised by permanent dilation of bronchi and bronchiole caused by destruction of muscle and elastic tissue resulting from or associated with chronic necrotizing inf
Cause of bronchiectasis
1.Congenital
Cystic fibrosis
Intralobar sequestration of lung
Immunodeficiency states
Ciliary dysfunction syndromes
2. Acquired
A.Post infectious conditions
Necrotizing pneumonia by
Bacteria:
m. Tb, staph aureus, h influenzae, pseudomonas
Virus: adenovirus, influenza virus, hiv
B. Bronchial obstruction
. Tumors
. FB
. Mucous impaction
3.Immune disorders
. Rheumatoid arthritis
.Sle
.ibd
.post transplantation
. Idiopathic 50%
Complications of Bronchiectasis
Obstructive ventilatory insufficiency
Corpulmonale
Metastatic brain abscess
Amyloidosis
Asthma
Asthma is a heterogenous disease usually characterised by chronic airway inflammation and variable expiratory airflow obstruction that produces symptoms such as wheezing , shortness of breath chest tightness and cough which vary over time and intensity
Pneumonia
It can be broadly defined as infection of lung parenchyma with consolidation
Classify pneumonia
Anatomically
Lobar pneumonia
Bronchopneumonia
Atypical pneumonia
Clinically
1.Community acquired acute pneumonia
2.community acquired atypical pneumonia
3.chronic pneumonia
4.healthcare associated pneumonia
5.aspiration pneumonia
6.nectrotizing pneumonia
7. Pneumonia in immunocompromised person
Acc to causes
1.Bacterial
S.pneumonie
H.influenzae
K.pneumonie
Mycoplasma pneumoniae
2. Viral
Influenza
Parainfluenza
Measles
Corona virus
3.fungal
Candida
Actinomycetes
Histoplasma
4. Protozoal
Entameoba
Toxoplasma gondi
- Rickettsial
Typhus
Q fever
Diff btw lobar and broncho pneumonia
Lobar : at any age
Broncho: extremes of age
Lobar: s pneumoniae 90-95%
Kleb pneumoniae
S aureus
S pyogens
Broncho:
Staph aureus
S pyogens
H influenzae
E coli
Lobar: lobar or segmental involving the whole lobe
Broncho: patchy distribution involving more than 1 lobe
Lobar : good prognosis
Broncho: relatively worse prognosis
Community acquired atypical pneumonia
Denotes
Moderate amount of sputum
No physical findings of consolidation
Moderate degree of wbc count
Lack of alveolar exudate
Nosocomial pneumonia
Nosocomial or hospital acquired pneumonia are pumlonary infections acquired in course of hospital stay
Commonly in immunosuppressed pts
Pts with prolonged antibiotic use
Pts with invasive devices
Organisms responsible are gram neg rods like enterobacteraciae and pseudomonas sps
Gram postive cocci
Staphylococcus aureus
Sites of tb
Lung
Lymph node
Nose
Tonsil
Skin
Git
Never involves
Cardiac muscle myocardium
Skeletal muscle
Thyroid
Diff btw primary and secondary tb
Primary occurs in previously unexposed persons
Sec occurs in previously exposed persons
Pri source is exogenous
Sec source is endogenous
Pri site is sub pleural lesions ie. Lower part of upper lobe and upper lart of lower lobe
Sec site is apex of upper lobe usually in rt lung
Pr is usually asymptomatic
Sec is symptomatic
Pr Cavitation is less common
Sec cavitation is more common
Pr caseation is less common
Sec caseation is more common
Pr lymph node involvement is more common
Sec ln involvement is less common
Doagnosis of tb
History and physical examination
Afb staining and culture of sputum
Esr is high
Gene Xpert for detection of organisms
Tuberculin skin test or monteux test
Monteux test or tuberculin test
Infection with M.Tuberculosis typically leads to development of delayed type of hypersensitivity To Tuberculosis Antigen which can be detected by this test.
this test has no diagnostic value and only indicates the occurrence of past and recent infection.
when the reaction is positive the test becomes positive about 2 to 4 weeks after infection. reagent: purified protein derivatives (ppd) recommended tuberculin dose 5 tuberculin units 5 TU -0.1 ml
Interpretation
positive reaction: induration exceeding 10 mm
negative reaction: induration less than 6 mm
doubtful reaction :induration between 6 and 9 mm
False positive and false neg tuberculin test
False pos
Prior bcg
Atypical mycobacterial inf
False neg
Viral inf
Sarcoidoisis
Malnutrition
Malignancy
Hodgekin lymphoma
Immunosuppression
Incorrect ppd injection
Lung tumors who classificatikn
- Adenocarcinoma
Acinar
Broncho alveolar
Solid
Papillary
Mixed - Squamous cell carcinoma
3.Small cell carcinoma
4.Large cell carcinoma
5.Adenosquamous carcinoma
6.Carcinoma of sarcomatoid element
7.Carcinoid tumor
Typical
Atypical
Clinical classification of lung tumors
Small cell carcinoma
15%
Non small cell carcinoma 85%
Adenocarcinoma
Sq cell carcinoma
Large cell carcinoma
Carcinoid tumor
Lung tumors
Benign:
Adenoma
Fibroma
Lipoma
Liomyoma
Hemangioma
Chondroma
Malignant
Primary : bronchogenic ca(90-95%)
Bronchial carcinoid tumor
Fibrosarcoma
Leimyosarcoma
Hodgekin and non hodgkin lymphoma
Secondary: from ca of breast colon kidney uterus ovary testes thyroid or
Osteogenic and other sarcomas
Risk factors of lung carcinoma
Tobacco smoking
Industrial hazard
Molecular genetic
Air pollution
Precursor lesions
Precursor lesions
1.Squamous dysplasia and carcinoma insitu
2.atypical adenomatous hyperplasia
3. Adenocarcinoma insitu
4.diffuse idiopathic pulmonary neuroendocrine cell hyperplasia
Common lung cancers
Adenocarcinoma
Most common in females and non smokers
Small cell ca and sq cell ca most common in males and smokers
Premalignant conditions of lungs
Precursor lesions
Fate of primary tb
95% of cases develop cell mediated immunity and heal by fibrosis
Progressive pulmonart tb
Progresses to sec tb or reinfection
Fate of sec tb
Fibro calcific scar
Progressive pulmonary tb
Miliary pulmonary tb
Systemic miliary tb
Intestinal tb
Isolated organ tb
Lymphadinitis
Clinical features of tb
Malaise
anorexia
wt loss
night sweats
Low grade fever
