Respiratory Flashcards
Asthma
- chronic inflammatory disease, with intermittent airway obstruction and hyper-reactivity -> bronchoconstriction and increased mucus production
- dyspnoea, cough, expiratory wheeze
- worst early morning
- triggers eg cold, exercise, allergens, smoking
- acid reflux, other atopic disease associated
Ix
- FEV1/FVC ratio <0.7 (same lung capacity, just can’t get air out as quickly)
- FEV1 <80% predicted
- peak flow monitoring
- CXR (hyperinflation)
- allergy testing with skin prick
Asthma management
Step 1 - low dose ICS preventor (beclomethasone) and SABA (salbutamol)
Step 2 - add LABA (salmeterol/eformetasol/fluticasone)
Step 3 - add montelukast or increase dose ICS
Step 4 - refer to specialist care (oral prednisolone / immune modulator)
- beware oral candidiasis, wash mouth after ICS
- consider inhaler technique, + the environment! (dry powder if poss)
Chronic obstructive pulmonary disease
= emphysema + chronic bronchitis
- older age at onset, smoking / pollution history, minimal diurnal variation
- chronic bronchitis = cough + sputum for most days for 3mo of 2 years
- emphysema = histologically enlarged air spaces distal to terminal bronchioles
Pink puffers - normal sats, breathless but not cyanosed, may -> type 1 resp failure
Blue bloaters - low sats and high CO2, cyanosed but not breathless, may -> cor pulmonale (RHF)
- risk acute exacerbations and infections, + carcinoma, pneumothorax (bullae rupture), resp failure
Ix and Mx of COPD
Ix
- FEV1/FVC ratio <0.7 (same lung capacity, just can’t get air out as quickly)
- FEV1 <80% predicted
- pulse oximetry low (88-92%)
- ABG
- CXR (hyperinflation)
- bloods/sputum for infection
- ECG - RVH
Mx
- chronic stable - SABA or SAMA, then + LABA/LAMA, then + ICS
+ smoking cessation!, vaccinations
- acute - nebulised SABA, controlled oxygen therapy, IV steroids, abx
Community acquired pneumonia
Typically - strep pneumoniae - haemophilus influenzae - moraxella catarrhalis \+ atypicals eg mycoplasma, staph aureus, legionella, chlamydia - viral in 15%
- fevers, rigors, malaise, anorexia, dyspnoea, cough, purulent sputum, haemoptysis, pleuritic chest pain
CURB-65 (confusion AMTS<8, urea>7, resps>30, BP<90 or 60, age>65) - 0-1 - home abx - 2 - hospital therapy - 3 - high mortality, consider ITU
Ix
- CXR
- FBC, ABG, U+Es, glucose
- urine (if ?atypicals)
- sputum + MC+S (bronchoscopy culture more accurate)
Mx
- abx - oral amoxicillin / doxycyline / clarithromycin, co-amoxiclav + clarithromycin if high severity
- maintain O2, fluids, VTE prophylaxis
(Pneumocystitis pneumoniae = AIDS or immunosuppression)
Hospital acquired pneumonia
>48hr after hospital admission Typically - enterobacter (E coli, klebsiella, salmonella) - staph aureus \+ atypical pseudomonas
- fevers, rigors, malaise, anorexia, dyspnoea, cough, purulent sputum, haemoptysis, pleuritic chest pain
Ix
- CXR
- FBC, ABG, U+Es, glucose
- urine (if ?atypicals)
- sputum + MC+S (bronchoscopy culture more accurate)
Mx
- culture, broad spec abx, then narrow down
- abx - co-amoxiclav, doxycycline, piperacillin or ceftriaxone if high severity
- maintain O2, fluids, VTE prophylaxis
Lung cancer
- carcinoma of bronchus usually, 90% from smoking
Non small cell mostly - squamous cell, adenocarcinoma, large cell
Small cell - from endocrine cells and secrete paraneoplastic hormones eg ACTH - highly malignant and metastasised by time of diagnosis
- cough, haemoptysis, dyspnoea, chest pain
- weight loss, lethargy, anorexia
- recurrent pneumonias
+ nerve palsies, SVC obstruction, Horner’s syndrome (Pancoast’s tumour), signs of mets
Ix
- CXR (central mass, hilar lymphadenopathy, pleural effusion)
- cytology of sputum and pleural fluid
- FNA or biopsy
- CT to stage
- bronchoscopy for sample and assess operability
- PET-CT
Mx
- surgery
- radiotherapy
- chemotherapy
- supportive
Mesothelioma
- aggressive epithelial neoplasm in pleura, and sometimes peritoneum / other organs
- occupational exposure to asbestos (maybe 45yrs ago), presents age 70-80s
- chest pain, dyspnoea, weight loss, clubbing, recurrent pleural effusions
- signs of mets - lymphadenopathy, hepatomegaly, bone pain
Ix
- CXR / CT - unilateral pleural thickening/ calcified plaques, pleural effusion
- bloody pleural fluid when tapped
- thoracentesis, exudative (Light’s criteria)
Mx
- chemotherapy, but poor prognosis
Bronchiectasis
= dilation and destruction of the terminal bronchioles with chronic inflammation
+ infection - mainly H influenzae, strep pneumoniae, staph aureus, pseudomonas aeruginosa
Causes
- congenital eg CF
- post-infection - measles, pneumonia, TB, HIV (esp if recurrent or severe)
- bronchial obstruction from tumour
- persistent cough + LOTS purulent sputum, intermittent haemoptysis
- clubbing, coarse expiratory creps, wheeze
Ix
- sputum culture
- CXR (cystic shadows, thickened bronchial walls)
- high resolution CT
- spirometry (obstructive)
- bronchoscopy
Mx
- exercise and chest physio
- abx, long-term if >3 per year
- nebulised salbutamol if co-morbidities
- corticosteroids
- surgery if localised disease or for severe haemoptysis
Interstitial lung disease
- insult to lung -> abnormal healing -> fibrosis, so more difficult for alveoli to perform gas exchange (oxygen affected much more than CO2)
Causes
- inhaled - inorganic (asbestos) or organic (hypersensitivity pneumonitis)
- drug-induced (abx, antiarrhythmics)
- connective tissue diseases
- infection (TB, pneumocystic pneumonia)
- idiopathic (MAIN CAUSE)
- malignancy
Presentation
- dyspnoea on exertion
- non productive cough
- abnormal CXR or CT
- restrictive spirometry
Idiopathic pulmonary fibrosis
- commonest type of idiopathic interstitial lung disease
- rare, chronic, life-threatening disease, where scar tissue forms for unknown reason
- dry cough, exertional dyspnoea, malaise, weight loss, arthralgia
- cyanosis, clubbing, fine end-inspiratory creps
Ix
- CXR - reduced lung volume, honeycomb lung
- CT - needed for diagnosis
- bloods + ABG, immunoglobulins raised, maybe ANA +ve
- restrictive spirometry
- bronchoalveolar lavage
Mx
- supportive mostly (oxygen, opiates, pulmonary rehab)
- perfenidone (immunosuppressant and antifibrotic) emerging use - all for clinical trials
- 50% 5yr survival
Sarcoidosis
- idiopathic cause of interstitial lung disease
- chronic non-caseating granulomatous disorder affecting lungs, skin and eyes
- dry cough, dyspnoea, fatigue, arthralgia, wheezing, lymphadenopathy, eye symptom
- in 20s and 40s presents, fhx is RF
Ix
- diagnosis of exclusion, only by biopsy
- CXR, bloods (look at all organ systems)
Mx
- depends on severity - ICS, oral steroids, cytotoxics immunosuppression (methotrexate/azathioprine), lung transplant
- topical steroids for skin/eye
Tuberculosis
- caused by Mycobacterium tuberculosis
- affects lungs + other systems (pleura, lymph, CNS, liver, bones, GI tract)
- notifiable disease
- inhalation -> caseous granuloma from Th1 and macrophages, so becomes not infectious, reactivation when immunocompromised
Presentation
- asymptomatic but with bacterial/radiological evidence
- cough (dry -> productive ± haemoptysis)
- low grade fever + night sweats
- weight loss
- malaise / fatigue
+ pleuritic chest pain, enlarged lymph nodes, bone pain, urinary symptoms
Ix and Mx
- CXR (fibro-nodular opacities or miliary spread)
- sputum +ve for acid fast bacilli, Ziehl-Neelson stain + culture
- tuberculin skin testing
- rifampicin in latent infection
- isoniazid and pyridoxine in active TB
Acute asthma attack severity grading
Moderate - increase in symptoms, PEF 50-75% predicted, no other features as below
Severe - PEF 33-50% predicted, RR>25, HR>110, inability to complete sentences
Life-threatening - PEF<33% predicted, SaO2<92%, reduced consciousness, cyanosis
Management of acute asthma attack
- usually viral (only give abx if see consolidation on CXR or purulent sputum)
- or triggered by environmental allergen / irritant
- Th2 IgE response triggering inflammation, bronchospasm and airway occlusion
Mx
- A-E
- measure peak flow, ECG, bloods (only ABG if life-threatening), CXR
- oxygen (to target sats)
- salbutamol (nebulised, beware hyperkalaemia, tremor, palpitations, lactic acidosis)
- hydrocortisone PO or IV if life-threatening (or prednisolone)
+ magnesium sulfate if life-threatening / non-responsive
+ theophylline PO or aminophylline IV last line
±heliox
D/C with 5d oral steroids
? step up, assess inhaler technique
GP follow up after 2d
Can’t go home until stable on meds for 24hrs
Exacerbation of COPD
- worsening of symptoms, including dyspnoea, cough, wheeze, change in sputum colour / volume, tachypnoea
- tends to be worse in winter months
- commonly infectious (H influenzae, Strep pneumoniae, moraxella catarrhalis)
- or smoke/pollutant exposure
GOLD classification
- mild FEV1>80% predicted
- moderate 50-80%
- severe 30-50%
- very <30%
- CXR (hyperinflation, flat diaphragm)
- ECG
- ABG (respiratory acidosis) + bloods
- sputum MC+S
Mx
- SABA ± abx
- oral steroids + airway clearance
- oxygen ± BiPAP
- broad spec abx -> narrow after MC+S
Pneumothorax
= air in pleural space
- SMOKING, tall and slender
- primary spontaneous = young with no prior resp disease
- secondary spontaneous
- traumatic
- sudden sharp pleuritic chest pain
- dyspnoea
- hyperexpansion, absent breath sounds, hyper-resonant
Mx
- primary:
- <2cm - discharge
- > 2cm - aspirate
- if fails, chest drain + admit
- secondary:
- <2cm - aspirate
- > 2cm chest drain + admit
Pulmonary embolism
- from VTE in legs or pelvis (via right side of heart)
- pleuritic chest pain, dyspnoea, tachypnoea, cough ±haemoptysis, tachycardia, fever, signs of DVT
RFs: Travel Hypercoagulable Recreational drugs Old Malignancy Birth control pill Obesity/obstetrics Surgery/smoking Immobilisation Sickness
Ix
- bloods, ABG, D-dimer (after Wells score if <4)
- ECG
- CXR normal
- CTPA if Wells>4 or D -dimer +ve
Mx
- oxygen if low sats
- morphine
- LMWH/fondaparinux
- fluid bolus if low BP
- thrombolysis if haemodynamically unstable
- -> long term anticoagulation on DOAC (or IVC filter if contra-indicated)
Pleural effusion
Transudates = protein conc <25
- due to raised venous pressure (HF, fluid overload, constrictive pericarditis)
Exudates = protein conc >35
- increased leakiness of capillaries due to infection, inflammation or malignancy
- asymptomatic or dyspnoea / pleuritic chest pain
- stony dull percussion, decreased expansion, diminished breath sounds
- blunting of costophrenic angles on CXR
- USS
- pleural biopsy
Acute respiratory distress syndorome
- direct lung injury, or secondary to sever systemic illness
- mortality >50%
Pulmonary
- pneumonia, gastric aspiration, inhalation, injury
Other
- shock, septicaemia (usually), haemorrhage, DIC, acute liver failure, pancreatitis, head injury, drugs/toxins
Need all four criteria:
- acute onset <7d
- bilateral infiltrates on CXR
- non-clinical heart failure (check BNP)
- refractory hypoxaemia with PaO2:FiO2<200 (arterial:inspired oxygen ratio)
- cyanosis, tachypnoea, tachycardia, peripheral vasodilation, bilateral fine inspiratory crackles
Mx - ITU
- resp support on CPAP
- circulatory support to maintain CO
- treat underlying cause (sepsis 6)
Obstructive sleep apnoea
- episodes of complete or partial upper airway obstruction during sleep
- obesity
- maxillomandibular anomalies
- sleep partner notices episodic cessation of breathing, then loud snore/gasping
Ix
- polysomnography - overnight test to calculate apnoea-hypopnoea index (if >15/hr then diagnostic)
- nasoendoscopy
Mx
- weight loss
- mandibular repositioning /tongue retaining device
- CPAP
- surgery
Hypersensitivity pneumonitis
- non-IgE mediated immunological inflammation, caused by repeated inhalation of non-human protein (eg bird droppings, mushroom workers, mould)
- type III or IV hypersensitivity reaction
- dyspnoea and cough
+ fever, malaise, anorexia, clubbing
Ix
- FBC (WCC)
- CXR - upper zone mottling/consolidation
- pulmonary function tests, restrictive pattern
Mx
- remove allergen
- oxygen
- PO prednisolone
Beta 2 receptor agonists
- bronchodilators, for asthma and COPD
- short acting eg salbutamol, for acute relief, takes 20 mins to work and can last 6 hours
- LABA eg salmeterol, eformeterol, preventors
- B2 agonism -> increased activation of cAMP, so inhibition of MLCK and activation of MLCP -> relaxation
SEs - tremor, headache, dizziness, tachycardia
Muscarinic 3 receptor antagonists
- bronchodilators, for asthma and COPD
- SAMA eg ipratropium bromide, in severe asthma attack
- LAMA eg tiotropium bromide, glycopyronium bromide, for preventor of COPD
- inhibits bronchoconstriction
SEs - dry mouth, cough, rarely urinary retention
