Respiratory Lectures Flashcards
What is bronchoscopy?
A diagnostic procedure used to obtain a small amount of lung tissue and fluid samples
Flexible bronchoscopy visualizes the lumen and mucosa of the trachea and airways.
When is bronchoscopy indicated?
Suspected lung cancer, mycobacterial disease, immunocompromised patients, refractory consolidation, significant hemoptysis
Ideally performed within 7 working days after decision.
What does a CRB65 score assess?
Mortality risk in patients with pneumonia based on confusion, respiratory rate, blood pressure, and age
Scoring: 0 = low risk, 1-2 = intermediate risk, 3-4 = high risk.
What are the indications for sputum culture in primary care?
Moderate- or high-severity community-acquired pneumonia
Blood and sputum cultures should be taken; consider urinary antigen tests.
What types of sputum are indicative of infection?
Rusty colored (pneumococcal), purulent (yellow-greenish), white milky (viral), foamy white (heart failure)
Bloody hemoptysis may suggest TB, lung cancer, or pulmonary embolism.
What is the significance of Gram staining in sputum analysis?
Differentiates bacteria by cell wall properties
Normal sputum should have >25 leukocytes and <10 epithelial cells per low power field.
What are the types of specimens for sputum culture?
Expectorated, transtracheal aspirates, translaryngeal aspirates, bronchoalveolar lavage
Saliva is not considered sputum.
What is the definition of asthma?
A heterogeneous disease characterized by chronic airways inflammation and variable respiratory symptoms
Symptoms include wheeze, shortness of breath, chest-tightness, and cough.
What is the FEV1/FVC ratio in the diagnosis of COPD?
≤ 0.7 and is incompletely reversible after bronchodilators
Indicates obstructive airway disease.
What are the key features of obstructive lung disease?
Narrowed airways, difficulty exhaling, hyperinflation, increased residual volume
Examples include asthma and emphysema.
What are the key features of restrictive lung disease?
Reduced lung expansion, difficulty inhaling, normal FEV1/FVC ratio
Examples include interstitial lung disease and obesity hypoventilation syndrome.
What is the purpose of lung function tests?
To measure how much air a patient can breathe out and how quickly
Vital for diagnosing obstructive and restrictive lung diseases.
What is the role of sputum culture in secondary care?
Used when patients are not responding to treatment or have specific risk factors
Helps manage pneumonia, bronchiectasis, bronchitis, or pulmonary abscess.
What is the significance of a positive acid-fast stain?
Indicates the presence of tuberculosis
Requires special media for culture and incubation for at least 6 weeks.
What is the expected outcome of a normal sputum culture?
Presence of normal upper respiratory tract flora
Includes Neisseria catarrhalis, Candida albicans, and some staphylococci.
What is the importance of follow-up chest X-ray after pneumonia?
To confirm resolution of pneumonia radiologically
Recommended 6 weeks after initial diagnosis.
What is the purpose of a flow-volume loop in spirometry?
To assess airflow obstruction and lung function
Helps differentiate between obstructive and restrictive lung diseases.
What is the significance of the FEV1 value in grading COPD severity?
FEV1 values categorize severity as mild, moderate, severe, or very severe
FEV1 > 80% is mild; FEV1 < 30% is severe.
What is the recommended action for a patient with worsening asthma symptoms?
Order spirometry to assess lung function
Helps in diagnosing and managing asthma.
What is the definition of sputum?
Material expelled from the respiratory tract, not saliva
Quality and quantity are crucial for effective analysis.
What are the contraindications for spirometry testing?
Active infection, pneumothorax, recent surgery
Ensures patient safety during the procedure.
What is asthma?
Asthma is a disease with many variations, usually characterised by chronic airways inflammation.
What are the two key defining features of asthma?
- A history of respiratory symptoms such as wheeze, shortness of breath, chest-tightness, and cough that vary over time and intensity
- Variable expiratory airflow limitation
What tests are used to investigate asthma?
- Peak flow
- Exhaled Nitric Oxide Testing (FeNO)
- Spirometry
- Bronchodilator reversibility (BDR)
What does peak expiratory flow rate (PEFR) measure?
The maximum someone can exhale with a full inspiration and a short maximal expiratory effort.
Describe the technique for measuring peak flow.
- Move peak flow meter indicator to zero
- Sit or stand up straight
- Take a deep breath in
- Place peak flow meter into the mouth with a tight seal
- Blow out hard and fast using chest and belly muscles for no more than two seconds
- Repeat three times and take the highest value
How long should a peak flow diary be maintained to help confirm a diagnosis of asthma?
2-4 weeks
What does a variable peak expiratory flow (PEF) reading indicate?
It can support an asthma diagnosis if there is diagnostic uncertainty after initial assessment.
What is considered a positive result for variability in peak flow readings?
More than 20% variability after monitoring at least twice daily for 2-4 weeks.
What does a FeNO level of 40 parts per billion (ppb) or higher indicate in adults?
It is considered a positive result confirming eosinophilic airway inflammation.
What is the significance of spirometry in asthma diagnosis?
It is used to detect airway obstruction, with a FEV1/FVC ratio normally greater than 70%.
What does a normal spirometry result when asymptomatic indicate?
It does not rule out asthma.
What does bronchodilator reversibility (BDR) measure?
The increase in expiratory airflow in response to an inhaled short-acting bronchodilator.
What is a positive result for bronchodilator reversibility in adults?
An improvement in FEV1 of 12% or more, and an increase of at least 200 mL in response to beta-2 agonists or corticosteroids.
What FEV1/FVC ratio indicates obstructive disease?
A ratio of less than 0.70.
What does an FEV1 increase of greater than 400 mL strongly suggest?
Asthma.
What is the diagnosis if FEV1/FVC is <0.70 and FEV1 increases <12% and <200 mL after bronchodilator administration?
COPD.
Fill in the blank: A FeNO level of _______ is considered a positive result in children.
35 ppb
True or False: A normal FVC indicates that the patient does not have asthma.
False
What should be considered if FEV1/FVC is <0.70 and FEV1 increases >12% and >200 mL?
Look at history and level of change to differentiate between asthma and COPD.
What are the main objectives in investigating infectious respiratory diseases?
Identify and investigate patients with:
* Tuberculosis
* Malaria
* Cystic fibrosis
* Whooping cough
* Alpha 1 antitrypsin deficiency
Recognise the indication for viral respiratory PCR and COVID-19 investigation in secondary care.
How many people are estimated to be infected with Mycobacterium tuberculosis globally?
Two billion people
This is over a quarter of the global population.
Which countries account for two-thirds of global tuberculosis cases?
- India
- Indonesia
- China
- The Philippines
- Pakistan
- Nigeria
- Bangladesh
- South Africa
What was the global death toll from tuberculosis in 2019?
1.4 million people
What are common risk factors for tuberculosis?
- Time spent in a high incidence country
- TB contact
- Current/history of being unhoused
- Imprisonment
- Drug or alcohol misuse
What are the symptoms of active tuberculosis?
- Fever
- Night sweats
- Weight loss
- Cough (pulmonary)
- Headache
- Lethargy
- Vomiting
- Confusion
- Seizures
- Coma
What tests are arranged if active tuberculosis is suspected?
- Chest x-ray
- Three respiratory sputum samples
For microscopy, culture, or specialist molecular tests.
What is the purpose of the Mantoux test?
To screen for latent tuberculosis
What does a positive Mantoux test indicate?
Induration ≥5mm
What are acid fast bacilli (AFB)?
Rod-shaped bacteria that can be seen under a microscope following a staining procedure
What is the stain used to visualize AFBs?
Ziehl-Neelsen (ZN)
What is the treatment regimen for active tuberculosis?
- Rifampicin
- Isoniazid
- Pyrazinamide
- Ethambutol (or Moxifloxacin)
Monitor LFTs and color vision (Ethambutol).
What is the definition of malaria?
A disease caused by Plasmodium parasites transmitted through mosquito bites.
What should be suspected in anyone with a fever following travel to an endemic area?
Malaria
What is the gold standard investigation for malaria?
Thick and thin blood film microscopy
What is the universal newborn screening test for cystic fibrosis in the UK?
Blood spot immunoreactive trypsinogen (IRT) concentration
What is the average incidence of cystic fibrosis in the UK?
1 in every 2,500 babies
What is the main cause of cystic fibrosis?
Mutations in the CFTR gene on chromosome 7
What are the stages of whooping cough?
- Catarrhal stage
- Paroxysmal stage
- Convalescent stage
What is the causative organism of whooping cough?
Bordetella pertussis
What is the typical presentation of whooping cough?
Cough that is not improving, whoop, apnoea, post-tussive vomiting, cyanosis
What is alpha-1 antitrypsin deficiency?
An inherited autosomal recessive disorder affecting the protein produced in the liver that protects tissues
What is a common presenting symptom of alpha-1 antitrypsin deficiency?
Dyspnoea, cough, sputum production
What tests are performed to diagnose alpha-1 antitrypsin deficiency?
- Serum level of alpha-1 antitrypsin
- Lung function tests
- Imaging
- Skin biopsy
What are the indications for performing a viral respiratory PCR?
Acute history of:
* Fever
* Headache
* Cough
* Sore throat
* Myalgia
* Coryzal symptoms
What is the first-line test for SARS-CoV-2 virus?
Reverse transcriptase PCR (RT-PCR)
What are common symptoms that may prompt testing for COVID-19?
- New continuous cough
- Temperature >37.8°C
- Loss of, or change in, sense of smell or taste
