Respiratory Medicine Flashcards
What is asthma ?
Asthma is a chronic inflammatory disease of the airways. It causes reversible airway obstruction during an exacerbation.
Differentials for a wheeze
Acute asthma exacerbation
Bronchitis
Pulmonary oedema
PE
GORD
Allergy
Vocal cord dysfunction
What is the pathophysiology of asthma ?
There is airway epithelial damage - shedding and sub-epithelial fibrosis, basement membrane thickening.
There is an inflammatory response with eosinophils, T cells and mast cells.
The cytokines amplify the inflammatory response.
There is increased numbers of goblet cells secreting mucus.
Triggers for asthma
Smoking
URTI
Allergens such as pollen
Exercise ( + cold air )
Drugs ( aspirin and beta blockers )
Certain foods and drinks
Mild exacerbation of Asthma management
ABCDE
Aim for 94-98% with oxygen if needed
ABG if sats below 92%
5 mg nebulised salbutamol
40 mg PO prednisolone or ( IV hydrocortisone if PO not possible )
What extra steps in the management plan are there for a severe exacerbation of asthma ?
500 mg Nebulised Ipratropium bromide
Consider back to back salbutamol
How does asthma present ( history ) ?
Cough - dry , nocturnal
Wheeze
Breathlessness
Chest tightness
Atopy - genetic susceptibility to develop allergies
How does asthma present ( on examination ) ?
Raised RR
Raised pulse
Low oxygen sats
Bilateral wheeze
How is asthma diagnosed ?
Peak expiratory flow
Spirometry - reversible obstructive pattern
What are the steps in the stepwise management of asthma ?
Step 1 - SABA + low dose ICS
Step 2 - Add inhaled LABA to low dose ICS
Step 3 - increase ICS or add LTRA
Step 4 - specialists therapy
What is COPD ?
COPD is characterised by airflow obstruction. The airflow obstruction is usually progressive and not fully reversible. The disease is predominately caused by smoking.
Pathophysiology of COPD ?
COPD is an umbrella term which encompasses emphysema and chronic bronchitis. There is mucous gland hyperplasia and loss of cilial function.
There is also alveolar wall destruction causing irreversible enlargement of air spaces distal to the terminal bronchiole
There is also chronic inflammation and fibrosis of small airways.
What are the causes of COPD ?
Smoking
Inherited alpha - 1 antitrypsin deficiency
Industrial exposure such as soot
What is the outpatient COPD management ?
Smoking cessation
Pulmonary rehabilitation
Bronchodilators
Anti Muscarinics
Steriods
Mucolytics
Diet
LTOT if appropriate
What are the types of exacerbations of COPD ?
Infective - change in sputum volume and colour
- fever
- raised WCC +/- raised CRP
Non infective
Management of COPD exacerbation ?
ABCDE approach
Give oxygen and aim for 88-92%
Nebulised salbutamol and Ipratropium
Steriods - prednisolone 30 mg
Antibiotics if purulent sputum or raised WCC
CXR
Consider IV aminophylline
What are the common organisms for community acquired pneumonia ?
Streptococcus pneumoniae
Haemophilus Influenzae
Moraxella catarrhalis
What are the common organisms for hospital acquired pneumonia ?
E. coli
MRSA
Pseudomonas
What are the common organisms for an atypical pneumonia ?
Legionella pneumophila
Chlamydia pneumoniae
Mycoplasma pneumoniae
Common differentials for CXR consolidation ?
Pneumonia
TB - usually upper lobe
Lung cancer
Lobar collapse
Haemorrhage
Investigations for pneumonia ?
Prompt CXR
FBC, U&E, CRP and sputum culture
ABG if sats are low
If there is a high CURB-65 score perform an Atypical pneumonia screen - serology and urine legionella test
How do you assess the severity of pneumonia ?
CURB-65
Confusion
Urea above 7 mmol/L
RR above 30
BP lower than 90 systolic and 60 diastolic
Above 65 years
Management of Pneumonia ?
ABCDE approach
Assess if any features of sepsis
Mild - moderate = 5-7 days of amoxicillin ( doxycycline if penicillin allergy )
Moderate - severe = co-amoxiclav and clarithromycin / doxycycline
Symptoms for a PE ?
Chest pain
SOB
Haemoptysis
Risk factors for a PE ?
Surgery
Pregnancy
Fracture or varicose vein
Malignancy
Reduced mobility
Previous DVT
If there is an unprovoked PE what should be considered ?
Malignancy
Thrombophilia
Management for a PE ?
ABCDE
Oxygen if hypoxic
Analgesia if there is pain
Subcut LMWH
Should be fully anti coagulated once confirmed on CTPA
What extra steps are given if there is a massive PE ?
Thrombolysis with IV Alteplase
What are contraindications for thrombolysis ?
ABSOLUTE
Haemorrhagic or ischaemic stroke in last 6 months
CNS neoplasia
Recent trauma or surgery
GI bleed in the last month
Bleeding disorder
Aortic dissection
RELATIVE
Warfarin / DOAC
Pregnancy
Advanced liver disease
Infective endocarditis
What are some clinical features of TB ?
Fever
Nocturnal sweats
Weight loss
Malaise
Cough +/- purulent sputum / haemoptysis
+/- pleural effusion
Differential diagnosis for haemoptysis
Infection -
- pneumonia
- TB
- bronchiectasis / CF
Malignancy -
- lung cancer
- mets
Others -
- PE
Risk factors for TB ?
Past history
Known contact with someone with TB
Born in country with high TB incidence
Foreign travel to a country with high incidence
Evidence of Immunosuppression
Management of respiratory TB ?
ABCDE + aim to culture whenever possible
If productive cough - x3 sputum samples
Consider bronchoscopy if no productive cough
Routine bloods + HIV test and vitamin D levels
Consider CT chest
Start empirical antibodies if waiting for diagnosis ( if suspecting pneumonia or TB )
Start anti-TB therapy if severely unwell after sending cultures.
(Treatment usually started before diagnosis confirmed ).
Notify public health
What is given in anti-TB therapy ?
2 months of 4 antibiotics - rifampicin, isoniazid, Pyrazinamide and ethambutol
Then 4 ,months of 2 antibiotics - rifampicin and isoniazid
What monitoring is needed when taking anti-TB therapy ?
LFT’s
Compliance so direct observed therapy is sometimes used
TB treatment has side effects
What are some major side effects of TB medications ?
Rifampicin - Hepatitis, Rashes, orange secretions
Isoniazid - hepatitis, rashes, peripheral neuropathy and psychosis
Pyrazinamide - hepatitis, rashes, Arthralgia and vomiting
Ethambutol - retrobulbar neuritis
What is bronchiectasis ?
Chronic dilatation of one or more bronchi. The
bronchi exhibit poor mucus clearance and there is predisposition to recurrent or chronic bacterial infection
What is the gold standard diagnostic test for bronchiectasis ?
High resolution CT
Causes of bronchiectasis ?
Post-infective - whooping cough or TB
Immune deficiency - hypogammaglobinaemia
Genetics - CF,
Obstruction - foreign body
What blood tests can be performed to assess the cause of the bronchiectasis ?
Immunoglobulin levels
CF genotype
HIV test
Rheumatoid factor
Auto antibodies
What is seen on CT in bronchiectasis ?
Signet rings
What are some of the common organisms causing bronchiectasis ?
Haemophilus influenzae
Pseudomonas aeruginosa
Moraxella catarrhalis
Management of bronchiectasis ?
Treat underlying cause
Physiotherapy - mucus and airway clearance
10-14 days antibiotics
Haemophilus influenzae - amoxicillin ( doxycycline )
Pseudomonas aeruginosa - Ciprofloxacin
Long term prophylactic antibiotics can be given - azithromycin
Pulmonary rehabilitation if MRC dyspnoea scare is higher than 3
what is a rare side effect of Ciprofloxacin that the patient should be made aware of ?
Achilles tendinitis
What is cystic fibrosis ?
CF is an autosomal recessive disease leading to mutations in the CFTR. This can lead to a multisystem disease characterised by thickened secretions
How is CF diagnosed ?
- One or more of the characteristic phenotypic features
- or a history of CF in a sibling
- or a positive newborn screening test result
AND
- An increased sweat chloride concentration
- or identification of 2 CF mutations
What are some features of CF ?
Chronic sinusitis
Repeated LTRI
Bronchiectasis
Liver disease
Portal hypertension
Gallstones
Steatorrhea
Nasal polyps
Pancreatic insufficiency
Diabetes
Oestoporosis
Arthralgia
Finger clubbing
What are some common complications of CF ?
Respiratory infections
Low body weight
Distal intestinal obstruction syndrome
CF related diabetes
What are some CF related advice ?
No smoking
Avoid other CF patients
Avoid friends / relatives with colds
Avoid jacuzzi’s
Clean and dry nebulisers thoroughly
Avoid stables, rotting vegetation and compost
Annual influenza vaccine
Management of CF ?
Physiotherapy for airway clearance
Exercise
Mucolytic treatment
Pancreatic enzyme replacement ( creon if there is pancreatic fibrosis )
Nutritional supplementation
Long term antibiotics
Symptoms of bronchiectasis ?
shortness of breath.
wheezing
Productive cough +/- haemoptysis
chest pain
What is interstitial lung disease ?
An umbrella term describing a number of conditions that affect the lung parenchyma in a a diffuse manner.
What are the common interstitial lung diseases ?
Usual interstitial pneumonia
Non-specific interstitial pneumonia
Extrinsic allergic alveolitis
Sarcoidosis
What is seen on pulmonary function tests in interstitial lung disease ?
Restrictive pattern
What are the classical findings in usual interstitial pneumonia ?
Finger clubbing
Reduced chest expansion
Fine inspiratory crepitations
( May show features of pulmonary hypertension )
What is the commonest type of pulmonary fibrosis ?
Usual interstitial pneumonia
What is extrinsic allergic alveolitis ?
It is a non-IgE hypersensitivity reaction due to inhalation of organic antigens to which the body has been sensitised causing an inflammatory response.
( also known as hypersensitivity Pneumonitis )
How soon after exposure does a reaction occur in extrinsic allergic alveolitis ?
How long does it take to settle after the repsonse ?
Short period 4-8 hours
1-3 days
What is the difference between acute and chronic extrinsic allergic alveolitis ?
Acute is usually reversible while chronic is less reversible
What are the common drug causes of extrinsic allergic alveolitis ?
Amiodarone
Bleomycin
Methotrexate
Nitrofurantion
Penicillamine
What is sarcoidosis ?
A multisystem inflammatory condition of unknown cause.
Forms caseating granulomas
Commonly affects the resp system but can affect any organ
What investigations should be done if suspecting sarcoidosis ?
PFT’s
CXR
Bloods - FBC, U&E, calcium
Urinalysis - calcium
ECG, ECHO & cardio MRI
CT/ MRI ( if headaches and suspecting neuro sarcoidosis
Symptoms of extrinsic allergic alveolitis ?
Acute ( hours after exposure ) - non-productive cough, SOB, fever, malaise
Subacute ( weeks after exposure ) - productive cough, SOB
Chronic ( months to years after exposure ) - SOB, productive cough, weight loss, clubbing
Investigations for extrinsic allergic alveolitis ?
CXR -
High resolution CT
Bloods - FBC ( low Hb ), raised CRP
PFT’s
General Interstitial lung disease management ?
Depends on underlying pathology
Remove exposure ( pet birds, drugs )
Stop smoking
Treat infective exacerbation
Oxygen is resp failure
Palliative care
Symptoms of sarcoidosis ?
SOB
Dry cough
Wheeze
Fatigue
Arthralgia
Treatment for sarcoidosis ?
Systemic steroids for symptomatic lung disease
( IV if acutely unwell )
Bisphosphonates for osteoporosis protection
If severe consider lung transplant
Most common cause of lung cancer ?
Smoking