Respiratory Flashcards

Question

Describe the features of asthma

Answer 1

- Reversible airway obstruction- episodes of bronchospasm due to hyper- responsiveness - Immunologically mediated type 1 usually (hypersensitivity to antigens) - Incidence and prevalence in children and adults has increased substantially - Recurrent episodes of wheezing, SOB, chest tightness and cough - Over inflation of lungs - fail to collapse properly - Mucus plugs in bronchi and bronchioles infiltrated with eosinophils

Answer 2

- Increased pulmonary capillary hydrostatic pressure and or increased pulmonary capillary permeability - Shift of water from intravascular compartment into interstitial lung spaces Depends on 3 factors 1. Capillary hydrostatic pressure 2. Plasma oncotic pressure (due to plasma proteins) 3. Permeability of vascular wall Fluid in lung deposited in interstitial spaces- lung able to mop up excess fluid via lymphatics until a threshold- this is when fluid spills in alveoli -Frothy fluid in airways, distended sub pleural lymphatics, enlarged hilar lymph nodes - SOB, Orthopnoea, Cough, hypoxia- interference with gas exchange due to fluid deposition - Paroxysmal nocturnal dyspnoea - X-ray- kersey B lines , upper lobe diversion, bat wing hilar regions Microscopically -Fluid in alveolar spaces pink staining, beads on a string congested appearance, heart failure iron macrophages( yellow staining)

Answer 3

Cardiogenic causes - LVF -Ventricular and supraventricular tachycardias -Mitral valve disease - Left atrial myxomas -Constrictive pericarditis, pleural effusion Other -IV fluid overload -Venous occulsive disease of the lung -Severe anaemia -Dilution of plasma proteins -ARDS- cytotoxic/ irritant oedema due to capillary endothelial damage- loss of water, fibrin and fibrinogen in diffuse alveolar damage - Cerebral injury - Excessive adrenergic release from hypothalamus - neurogenic pul oedema - Renal failure - hypoproteinaemia, fluid overload, hypertensive HF - High altitude - Acute mountain sickness - prevented by inhaling nitric oxide and CCBs -All increase lung capillary pressure

Answer 4

Features -Usually from a DVT - deep leg veins , deep pelvic veins, intracranial venous sinuses -Thromboemolbism most common Other types of embolism- Atheromatous, amniotic fluid (during labour), gas, fat, tumour, foregin material (IV drug user), Infected heart valves Travel from legs in circulation to RSH then to lungs and occlude the pulmonary artery Effects - Small emboli- can go unnoticed and lyse or if numerous can cause reduced liver function over time- pul HTN - Medium sized- resp and cardiac problems - due to ventilation perfusion mismatching - diagnostic tool - Large emboli- sudden death (saddle embolus)

Answer 5

- Prevent VTE in legs - Early mobilisation of surgical patients, TEDS and LMWHs - Risk factors- Virchows triad* - Immobilisation -Bed rest -Surgery -Obesity -Hyper-coagulable blood - Pregnancy -Reduce and remove risk factors - give anticoags

Answer 6

Accumulation of fluid within the pleural cavity can be - Transudates- low protein concentration, few cells , CCF, cirrhosis and nephrotic syndrome- think organ failure states - Exudates- lung malignancy- rich in protein- uraemia, mesothelioma, TB, chylothorax, rheumatoid disease, SLE - due to irritation of lung lining or parenchyma usually due to acute infection - Empyema- Frank pus * If it is a blood stained pleural effusion always think malignancy*

Answer 7

Presence of gas or air within the pleural space Spontaneous- young tall males due to developmental abnormality in upper lobes causing fibrosis and bull formation that may rupture Primary- Without pre-existing lung disease Secondary- With known lung disease Traumatic- penetrating/ blunt trauma to chest -Iatrogenic -Air may enter through chest wall in trauma- fractured rib OR -Air enters through pleural space via defect in visceral pleura - due to underlying diseases or spontaneous

Answer 8

-Infection affecting the distal airways especially alveoli Classification - Aetiological- viral, bacterial, fugal - Anatomical- bronchopneumonia or lobal pneumonia- can be seen on Xray - Clinical- nosocomial, community acquired - Histological - KEY CELL IS THE NEUTROPHIL POLYMORPH - moves into alveolar space from alveolar capillaries Treatment: Empirical therapy when acute or Isolate organism and determine sensitive for abx Two main organisms: Haemophilus influenzae and staph pneumoniae *Pneumonitis= illness causing inflam of alveoli with no infection*

Answer 9

- Due to successive infection of conductive airways - Starts as widespread bronchitis and progresses to surrounding acini - Focal infam centered on airways - Bilateral and lower lobes affected - Acute inflammation in bronchioles and surrounding alveoli - Abx and physio, oxygen supplementation - Slow healing will scar Risk factors - Old age/ infancy -Underlying debilitation - cancer, heart failure, chronic renal failure, CVA, malnutrition, alcoholism * Complication to anything that predisposes infection* - Acute bronchitis/ COAD/ CF - Post op period/ immobility - GA affects mucocillary clearance- limited resp movements due to absorption/ chest pain - Steroid therapy - Immune deficiency - HIV/AIDS Complications -Pleurisy, abscess, septicaemia

Answer 10

- Entire love uniformly affected - Inflam extends to pleura or a major fissure - often associated with a pleural effusion- if bacteria access the effusion may cause an empyema - Seen as endogenous infection- weakened host immunity can cause a variant of strep throat to spread to lungs - Step pneumoniae - gram positiv - infection can also lead to septicaemia and meningitis Ill quickly - features - Fever - Cough, rusty sputum - Acute pleuritic pain

Answer 11

- Congestion- enlarged heavy fluid in alveolar spaces - infected lobe- vascular congestion PMNS and bacteria - not many neutrophil polymorphs - Red hepatisation- Fibrin in alveolar space as proteinaceous fluid clots - liver like consistency where alveolar spaces are packed with neutrophils, RBCs and fibrin- lung looses colour from hilum to pleura - Grey hepatisation- firm lung where RBCs lyse and fibrinous exudate persists in alveoli - Resolution after 8-10 days- chemical dissolution of exudate and absorption through pulmonary lymph nodes

Answer 12

CAP -Gram positive, step pneumonia, Hinfluenzae, legionella , mycobacterium TB, staph aureus, Chlamydia pneumonia, mycoplasma pneumoniae, klebsiella pneumoniae (rare) HAP - Noscomial- after 2 or more days of admission - Mostly gram negatives- Klebsiella, E . Coli, Pseudomonas, enterobacter Atypical - Inflam in alveolar septa - Viruses, chalmydia, rickettsiae- will show chronic inflam in intersititum of lungs - Fever, dry cough, dyspnoea - Alveolar necrosis common in viral pneumonia Pneumocystis carinii- immunocompromised - Opportunistic fungi - Immunocompromised patients esp AIDS - Pink frothy exudate in alveoli - Silver stain- round organisms Legionella - contaminated air humidifiers and water cisterns

Answer 13

-Dilation of bronchi and suppruatiomn -Can be due to childhood illness/ infection but has declined due to vaccines -Abnormal dilation of bronchi -Cough, foul smelling sputum, haemoptysis Causes -Obstruction of bronchus by tumour or foreign body -Cystic fibrosis -Immotile cilia syndrome -Immunodeficiency -Idiopathic -Measles Complications -Lung abscess, brain abscess , empysema, amyloidosis

Answer 14

- Local area of suppuration walled off by granulation and fibrous tissue - Primary abscess- not preceded by other inflam process in lung - aspiration of infected oropharyngeal contents, risk factors loss of consciousness, loss of gag reflex, dysphasia, right side most common - Secondary abscess- Underlying condition causes it - Bronchial carcinoma -Foreign body in airway -Bronchiectasis -Staphyloccoal or klebsiella Outcomes: Spontaneous rupture into bronchus and pus spread throughout lung cyst and pneumatocele formation

Answer 15

- Reduced FEV1 - Normal FEV1:FVC ratio Ratio is the same but volume of air inhaled is lower

Answer 16

- Neuromuscular problems- difficult expanding thorax - amyotrophic lateral sclerosis - Chest wall- obesity - is a major cause - Pleural disease- stiffness and fibrosis of pleura - Stiff lungs- parenchymal lung disease - interstitial oedema- fluid in lung interstitum, cellular infiltration- chronic inflam cell infiltration, fibrosis- scarring of lungs Features - Restrictive lung function tests - normal ratio but low FEV1 - Breathless and hypoxic - Bilateral shadowing on lung radiology

Answer 17

- Area affected is the alveolar capillary wall +/- the intra-alveolar space - Chronic inflam leads to fibrosis and thus thickening of space between the capillary and alveolar walls- impaired gas exchange - Fibrosis leads to destruction of alveoli and decreased expansibility of the lung

Answer 18

1. Intra-alveolar fibrosis- caused by cryptogenic organising pneumonia, granulation tissue in alveolar lumen, eventually incorporated into alveoli walls to give interstitial fibrosis, cough, SOB, malaise, steroid responsive 2. Obliterative fibrosis- Destruction of multiple alveoli due to extensive fibrosis - usually end stage, end stage progressive diffuse alveolar damage (DAD) that leads to adult respiratory distress syndrome - think about the causes of this 3. Interstitial fibrosis- Classified into 2 groups a) Exudates- Damage to lining cells of alveoli cells and capillaries causing exudate formation - Affects lung base, asbestos, interstitial fibrosis (RA, SLE), interstitial oedema, ARDS, idiopathic pul fibrosis b) Granulomas- Collections of macrophages with/ without giant cells- inflam process leading to fibrosis - group 2 is called granulomatous inflammatory process - sarcoidosis, extrinsic allergic alveolitis, silicosis

Answer 19

- A type of interstitial fibrosis - Permanent alteration of lung structure due to inhalation of mineral dust - Due to exudates of transudates or granulomatous inflammation - Disease- asbestosis, silicosis, coal workers pneumoconiosis

Answer 20

- Inhaled asbestos fibres can induce chronic inflam and fibrosis - Asbestos bodies- dumbbell shaped by deposition of protein and iron on asbestos fibres - Diagnosis: Fibrosis and asbestos bodies - Lung biopsy needed for diagnosis to show fibrosis and asbestos bodies

Answer 21

- Chronic recurrent infection of the lung caused by mycobacterium tuberculosis - via resp route - Interstitial TB caused by mycobacterium bovid from infected milk - At risk groups: Homeless, prisoners, elderly, poor, malnourished, Immunosuppressed, alcoholism, chronic renal failure Mycobacterium tuberculosis- Ziehl nelson stain used to detect in tissue- PCR used for confirmation of diagnosis - important and culture may be slow 3-6 weeks Caseating granuloma- rimmed with palisading epitheliod histiocytes (macrophages that have changed to epithelial cell secreting interleukins), langhan's giant cells and inflammatory cells Primary TB- parenchymal nodule usually in upper lobe- Ghon focus - Involved hilar lymph nodes + ghon focus= primary complex/ ghon complex - Will have sub pleural distribution in primary- can occur in any lobe Secondary TB- reactivation - dormant viable mycobacteria or previously infected patient- caveatting lesions in upper lobe apices, caseous necrosis discharged into bronchi and cavities left formation of upper cavity in upper lung lobe