Respiratory Flashcards
Which part of the lung is most likely affected in aspiration pneumonia and why?
Right middle/lower lobes
Because the right bronchus is straighter and more vertical than the left so aspiration is most likely to affect lungs on the right
Lower lobes if patient sitting upright (gravity)
Components of CURB-65
Confusion
Urea > 7
Respiratory rate > 30
Systolic BP < 90 or Diastolic BP < 60
Age > 65
How many weeks after clinical resolution of pneumonia should patient have repeat chest X-ray?
6 weeks
Community Acquired Pneumonia: Common causative agents
Strep Pneumoniae (80%)
H. Influenzae (more common in COPD)
Viral: RSV, COVID-19 (15%), Influenza
Atypical:
Mycoplasma pneumoniae (younger patients)
Chlamydia pneumoniae (Elderly patients)
Legionella pneumoniae
Hospital Acquired Pneumonia: Common causative agents
Gram negatives:
- Klebsiella
- E. Coli
- Pseudomonas
MRSA
Staph Aureus
When to consider antibiotics in acute bronchitis?
Systemically unwell
Pre-existing co-morbidities
CRP of 20-100 (offer delayed prescription)
CRP > 100 (offer antibiotics immediately)
Antibiotic for acute bronchitis
Doxycycline
Pregnant or aged 12-17: Amoxicillin
Define Pneumonia
Signs of respiratory tract infection + New shadowing on CXR
Asthma DIAGNOSTIC tests
Spirometry and bronchidilator reversibility test
If > 17 yrs or still unsure in children:
FeNO test
All adults with suspected asthma should have both of the above tests
At what age can you test for asthma
> 5 years
Under 5 diagnosis made on clinical judgement
Positive FeNO test result
> = 40 ppb = positive test for asthma
Spirometry test positive result for asthma
FEV1 : FVC ratio < 70%
This is considered OBSTRUCTIVE
Bronchodilator reversibility testing positive result (asthma)
Positive test = improvement of FEV1 of of 12% or more
What is the relevance of testing for fractional expired nitrous oxide?
NO is produced in response to inflammation and expired
Uncontrolled asthma
Current meds: Salbutamol INH PRN
Using 3 x per week
What next?
+ ICS
E.g. beclometasone
Uncontrolled asthma
Current meds: Salbutamol + ICS
What next?
+ Long acting beta-2 agonist (LABA)
E.g. salmeterol/formoterol
** Can’t use LABA without ICS
They come in combined inhaler - Symbicort/Fostair (= MAST regimen)
Uncontrolled asthma
Current meds: Salbutamol + ICS/LABA (Symbicort)
What next?
+ LTRA (leukotriene receptor antagonist)
E.g. Montelukast
Uncontrolled asthma
Current meds: Salbutamol + ICS/LABA + Montelukast
What next?
Increase dose of ICS
If this doesn’t help refer to specialist and consider long term oral steroids (e.g. prednisolone)
Signs of poor control of asthma
Using SABA (reliever) >= 3 x per week
Night symptoms >= 1 x per week
Interfering with daily activities
Chest tightness, wheeze
Exacerbation in the last 2yrs
Signs of severe asthma attack
PEF 33-50% of best
RR >= 25
HR >= 110
Incomplete sentences
Accessory muscles
Hyper inflated chest
Pulses paradoxus (Decrease in sBP with inspiration)
Signs of life threatening asthma attack
PEF < 33% of best
SpO2 < 92%
Decreased HR and BP
Exhaustion / confusion
Silent chest
Cyanosis
ABG: Increased CO2, O2 < 8, acidotic
Management of Atelectasis
Position the patient upright
Chest physiotherapy
Types and causes of Atelectasis
Obstructive - e.g. mucus plug (COPD, CF), foreign body, tumour
Non-obstructive
- most commonly caused by anaesthesia
- compressive - pneumothorax, hernia, pleural effusion
- contraction - scar tissue
- adhesive - surfactant deficiency
What is atelectasis?
Collapse of alveoli and lung tissue
Escalation of care in acute asthma
- Oxygen
- Salbutamol Nebs
- Ipratropium bromide nebs
- Hydrocortisone IV or PO prednisolone
- Magnesium Sulphate IV
- Aminophylline/ IV salbutamol
Admission to hospital criteria for acute asthma exacerbation
All patients with life-threatening asthma
Severe asthma + fail to respond to initial treatment
Previous near fatal asthma attack
Pregnancy
An attack occurring despite already using oral steroids and present at night
Lights Criteria: Transudate
Used if: protein content is 25-30 g/L
Pleural:serum protein < 0.5
Pleural: serum LDH <0.6
Pleural fluid LDH <2/3 upper limit of normal
Light’s Criteria: Exudate
Used if: protein content is 25-30 g/L
Pleural:serum protein > = 0.5
Pleural: serum LDH > = 0.6
Pleural fluid LDH >2/3 upper limit of normal
Conditions that causes of transudate pleural effusion (4)
Congestive heart failure
Renal failure
Liver failure
Hypothyroidism
Conditions that cause exudate pleural effusion (I I I M M)
Inflammation: Trauma, RA, sarcoidosis, SLE
Infection: Pneumonia, TB
Infarction: PE, post-MI (dressler’s)
Malignancy (25% of effusions)
Medications: amiodarone, phenytoin
Pathophysiology of transudate pleural effusion
Movement of fluid from circulation —> pleural space
Caused by:
Increased hydrostatic pressure
Decreased capillary pressure
Pathophysiology of exudate pleural effusion
Production and secretion of fluid into pleural space
Increased capillary permeability
Pleural Tap/Aspiration: what should be tested for?
Microbiology
Cytology (80% sensitive for malignancy)
Clinical chemistry:
- Glucose
- LDH
- Protein
- pH
Organisms causing empyema
Strep Milleri
H. Influenzae
E. Coli
Staph Aureus
Pseudomonas
Management of a pleural infection (empyema)
- PLEURAL TAP
- pH < 7.2
- Low glucose
- High LDL
Parapneumonic effusion - straw colour with no organisms
Loculated empyema - pockets of semi-solid pus - IV Abx for 2 weeks
- CHEST DRAIN if symptomatic and:
- Frank pus (puruent/cloudy appearance) OR
- pH < 7.2 OR
- organisms cultured - DECORTICATION (thorascopy) - to remove restrictive layer of fibrous tissue, if long standing pus/thickened pleura
What is meant by transfer factor?
Aka - diffusing capacity
Result of a gas transfer test that measures how the lungs take up oxygen
Capacity to transfer gas from alveolar spaces into the alveolar capillary blood
Relevance of PaCO2 in acute asthma exacerbation
You would expect a low PaCO2 as the patient is hyperventilating
A normal or raised PaCO2 indicates the patient is tiring, and this suggests asthma is life-threatening
Serious side effect of salbutamol
Hypokalaemia - salbutamol drive potassium into cells
Features suggesting steroid responsiveness in COPD
Previous diagnosis of asthma
Higher blood eosinophil count
Substantial variation in FEV1 over time (> 400ml)
Substantial diurnal variation in peak expiratory flow (> 20%)
What is the relevance of the FEV1 / FVC ratio
Forced expiratory volume in the first second / the forced vital capacity of the lung
Normal = > 80 (age dependent)
<70 suggests airflow limitation (obstructive)
Normal/High suggests restrictive lung disease
Signs of COPD on CXR
Hyperinflation
Flat diaphragms
Decreased peripheral markings
What is COR PULMONALE ?
Abnormal enlargement (hypertrophy or dilation) of the right side of the heart as a result of lung disease or pulmonary vessel disease
Methods of smoking cessation
- Nicotine replacement
- Varenicline (nicotine receptor partial agonist)
- Bupropion (noradrenaline/dopamine reuptake inhibitor)
- E-cigs
Mucolytic medication used in COPD
Carbocisteine
R/v in 4 weeks - if not benefit stop
Used for chronic productive cough
Vaccinations needed in COPD patients
Pneumococcal
Flu vaccine
What is in a “COPD rescue pack”
STEROIDS - Prednisolone
ANTIBIOTICS
MRC Dyspnoea Scale
1 = only SOB on strenuous exercise
2 = SOB if hurrying / walking up hill
3 = SOB on flat
4 = Stops for breath after 100m
5 = SOB on dressing
Contraindications to chest drain insertion
INR > 1.3
Platelet count <75
Pulmonary Bullae
Pleural adhesions
Most common organism isolated form patients with bronchiectasis
Haemophilus influenzae
What condition has “signet ring” sign on CT?
Bronchiectasis
Dilated bronchus and accompanying pulmonary artery
Most common causes of an anterior mediastinum mass (4)
4 Ts
Teratoma
Thymic mass
Thyroid mass
Terrible Lymphadenopathy
TB drugs
RIPE
Rifampicin
Isoniazid
Pyrazinamide
Ethanbutol
Important SE of Rifampicin
Hepatitis
Orange urine and tears
Enzyme inducer (e.g. OCP)
Important SE of Isoniazid
Hepatitis
Neuropathy
Enzyme inducer (e.g. COCP)
Important SE of Pyrazinamide
Hepatitis
Arthralgia
Important SE of Ethambutol
Optic neuritis
(starts with loss of colour vision)
How long does sputum culture and microscopy take for TB
6 weeks
What is a Ghon focus and where is it found?
Radiologically detectable finding characteristic of primary TB
= caseating granuloma (tuberculoma)
predominantly in the upper part of the lower lobe and lower part of the middle or upper lobe
Most common organism causing COPD exacerbation
Haemophilus influenzae
Treatment of community aquired pneumonia following influenza infection
Flucloxacillin + amoxicillin
- this is because Straph aureus is common cause of CAP after influenza infection
When to admit someone with a pneumothorax
Primary pneumothorax and >2cm or <2cm and patient SOB
Secondary pneumothorax - All patients should be admitted for at least 24 hours (even if <1cm)
