Resp Flashcards
What is asthma
chronic inflammatory disorder of the airways caused by type 1 hypersensitivity
What are some risk factors for developing asthma?
- Personal or family history of atopy
- Maternal smoking, viral infections during pregnancy, and low birth weight
- Not being breastfed
- Exposure to allergens (e.g., house dust mites) and air pollution
- The ‘hygiene hypothesis’
What are common atopic conditions associated with asthma?
Atopic dermatitis (eczema)
Allergic rhinitis (hay fever)
What is occupational asthma and how is it diagnosed?
- caused by allergens in the workplace, such as isocyanates or flour
- diagnosed by observing reduced peak flow readings during workdays, with normal readings on days off.
What are the typical symptoms of asthma?
Cough (worse at night)
Dyspnoea (shortness of breath)
Wheeze
Chest tightness
What are the signs of asthma on examination?
Expiratory wheeze on auscultation
Reduced peak expiratory flow rate (PEFR)
What diagnostic tests are recommended for patients aged 17 years and older suspected of having asthma?
All patients should have:
* Spirometry with a bronchodilator reversibility (BDR) test
* Fractional exhaled nitric oxide (FeNO) test
What diagnostic tests should be performed on children aged 5-16 years suspected of having asthma?
- All children should have spirometry with a bronchodilator reversibility (BDR) test.
- If spirometry is normal or shows obstruction with a negative BDR test, a FeNO test should be requested.
How is asthma diagnosed in children under 5 years old?
Diagnosis should be made based on clinical judgment.
In asthmatics, what indicates a positive result on a bronchodilator reversibility (BDR) test?
An improvement in FEV1 of 12% or more
Typical spirometry results indicating asthma
Obstructive pattern:
* Reduced FEV1
* Normal FVC
* FEV1/FVC ratio < 70%
What is fractional exhaled nitric oxide (FeNO) used for in asthma?
- FeNO levels correlate with inflammation, especially eosinophilic inflammation, in asthma
- It helps assess the level of airway inflammation.
Describe the stepwise management of asthma in adults
- Short-acting beta agonist (SABA).
- SABA + low-dose inhaled corticosteroid (ICS).
- add Leukotriene receptor antagonist (LTRA).
- SABA + low-dose ICS + long-acting beta agonist (LABA); Continue LTRA depending on patient’s response to LTRA
- Switch ICS/LABA for a maintenance and reliever therapy (MART), that includes a low-dose ICS
- Increase the inhaled corticosteroid to a moderate dose
How do short acting beta agonists work
relaxing the smooth muscle of airways
Give a side effect of Short-acting beta-agonists
tremor
In the management of asthma,how frequently should inhaled corticosteroids and LABAs be taken
Taken everyday, regardless of whether the patient has symptom
Give 2 side effects of inhaled corticosteroids
oral candidiasis and stunted growth in children
What are common symptoms of acute asthma?
Worsening dyspnoea, wheeze, and cough
What are the signs of moderate acute asthma in adults?
PEFR 50-75% of best or predicted
Speech normal
Respiratory rate (RR) < 25/min
Pulse < 110 bpm
What are the signs of severe acute asthma in adults?
PEFR 33-50% of best or predicted
Unable to complete sentences
Respiratory rate (RR) > 25/min
Pulse > 110 bpm
What are the signs of life-threatening acute asthma?
PEFR < 33% of best or predicted
Oxygen saturations < 92%
‘Normal’ pC02 (4.6-6.0 kPa)
Silent chest, cyanosis, or feeble respiratory effort
Bradycardia, dysrhythmia, or hypotension
Exhaustion, confusion, or coma
What is the significance of a normal pCO2 during an acute asthma attack?
A normal pCO2 (4.6-6.0 kPa) indicates exhaustion, which classifies the asthma attack as life-threatening
What is the significance of a raised pCO2 during an acute asthma attack?
pC02 >6.0 kPa indicates near-fatal asthma
When is an ABG indicated in the management of an acute asthma attack
only if oxygen sats <92%
When is a chest Xray indicated in the management of an acute asthma attack
life-threatening asthma
suspected pneumothorax
failure to respond to treatment
Who should be admitted to the hospital for an acute asthma attack?
- All patients with life-threatening asthma
- Patients with severe asthma who fail to respond to initial treatment
- Patients with a previous near-fatal asthma attack
- Pregnant patients with a severe attack even if they initially improve with treatment
- experience an attack despite using oral corticosteroids
- Patients presenting at night
How should oxygen be administered in acute asthma management?
- If hypoxaemic, start supplemental oxygen.
- For acutely unwell patients: give 15L via a non-rebreather mask, then titrate to maintain SpO2 at 94-98%.
How is bronchodilation used to manage acute asthma?
- High-dose inhaled SABA (e.g. salbutamol, terbutaline).
- For non-life-threatening asthma: can be given via pMDI or oxygen-driven nebulizer.
- For life-threatening asthma: nebulised SABA
What corticosteroid treatment is recommended for acute asthma?
- Prednisolone 40-50mg orally daily for at least 5 days or until recovery.
- IV hydrocortisone if they can’t tolerate oral meds
- Continue regular inhaled corticosteroid therapy during the acute attack.
When is ipratropium bromide used in acute asthma?
*should be given to all patients with severe or life-threatening asthma or those who haven’t responded to SABA and corticosteroids.
* Administer nebulised ipratropium bromide, a short-acting muscarinic antagonist.
What additional treatments may be considered for severe/life-threatening asthma?
- IV magnesium sulphate (evidence mixed but commonly used in severe cases).
- IV aminophylline (considered after consulting senior staff).
- Senior critical care support may be needed for unresponsive patients, including:
Intubation and ventilation
Extracorporeal membrane oxygenation (ECMO)
What criteria should be met before discharging an acute asthma patient?
- Stable on discharge medication (no nebulizers or oxygen) for 12-24 hours.
- Inhaler technique checked and recorded.
- PEF > 75% of best or predicted.
What is Chronic obstructive pulmonary disease (COPD)
Progressive condition involving airway obstruction, chronic bronchitis and emphysema
What is chronic bronchitis
long-term symptoms of cough and sputum production due to inflammation in the bronchi
What is emphysema
damage and dilatation of the alveolar sacs and alveoli, decreasing the surface area for gas exchange
Give 3 causes of COPD
- smoking
- Alpha-1 antitrypsin deficiency
- coal
Describe a typical presentation of COPD
- cough: often productive
- dyspnoea
- wheeze
- recurrent resp infections
What investigations should be done when diagnosing COPD
- post-bronchodilator spirometry to demonstrate airflow obstruction and minimal reversibilty
- chest x-ray: exclude lung cancer
- FBC: exclude secondary polycythaemia
- BMI
What may be seen on a chest Xray of COPD
- hyperinflation
- bullae: if large, can mimic a pneumothorax
- flat hemidiaphragm
How is COPD severity graded based on FEV1?
Stage 1 (Mild): FEV1 > 80% of predicted
Stage 2 (Moderate): FEV1 50-79% of predicted
Stage 3 (Severe): FEV1 30-49% of predicted
Stage 4 (Very Severe): FEV1 < 30% of predicted
What are the general management strategies for stable COPD?
- Smoking cessation advice, including nicotine replacement therapy
- Annual influenza vaccination
- One-off pneumococcal vaccination
- Pulmonary rehabilitation for those functionally disabled by COPD (usually MRC grade 3 and above)
What is the first-line bronchodilator therapy for stable COPD?
Short-acting beta2-agonist (SABA) or short-acting muscarinic antagonist (SAMA).
What step is taken if a COPD patient remains breathless or has exacerbations despite using short-acting bronchodilators?
The next step depends on whether the patient has ‘asthmatic features/features suggesting steroid responsiveness.’
What are the NICE criteria to determine whether a COPD patient has asthmatic/steroid-responsive features?
- Previous diagnosis of asthma or atopy
- Higher blood eosinophil count
- Substantial variation in FEV1 over time (at least 400 ml)
- Substantial diurnal variation in peak expiratory flow (at least 20%)
What is the treatment for COPD if there are no asthmatic features or features suggesting steroid responsiveness?
- add a long-acting beta2-agonist (LABA) + long-acting muscarinic antagonist (LAMA)
- if already taking a SAMA, discontinue and switch to a SABA
What is the treatment for COPD if asthmatic features or steroid responsiveness are present?
- LABA + inhaled corticosteroid (e.g. fostair, seretide)
- If symptoms persist, offer triple therapy (LAMA + LABA + ICS)
- Discontinue SAMA and switch to SABA if commencing LABA
In severe cases of COPD that are unresponsive to bronchodilators/steroids, what additional management options should be considered
- nebulisers
- oral theophylline
- Oral prophylactic antibiotic therapy: azithromycin
- Standby medication: short course of oral corticosteroids and oral antibiotics to keep at home
- Mucolytics
- Phosphodiesterase-4 (PDE-4) inhibitors (e.g. roflumilast)
When should oral prophylactic antibiotic therapy be considered for COPD patients?
In patients with frequent exacerbations who meet specific prerequisites:
* No smoking
* Optimised standard treatments
* CT thorax to exclude bronchiectasis
* Sputum culture to exclude atypical infections and TB
* LFTs and ECG - exclude QT prolongation
What are NICE’s recommendations for standby medication in COPD?
Offer a short course of oral corticosteroids and oral antibiotics to keep at home for patients who:
* Had an exacerbation within the last year
* Understand how to use the medication and when to seek help
What factors may improve survival in patients with stable COPD?
- Smoking cessation (most important if the patient still smokes)
- Long-term oxygen therapy (if criteria are met)
- Lung volume reduction surgery in selected patients
What is cor pulmonale
right sided heart failure caused by respiratory failure
Give 3 causes of cor pulmonale
- COPD (mc)
- PE
- Interstitial lung disease
What are some features of cor pulomale
- peripheral oedema
- raised jugular venous pressure
- systolic parasternal heave
- loud P2
What are the most common infective causes of COPD exacerbations?
Bacteria:
* Haemophilus influenzae (most common cause)
* Streptococcus pneumoniae
* Moraxella catarrhalis
Respiratory viruses
* human rhinovirus
What are the typical features of a COPD exacerbation?
- Increase in dyspnoea, cough, and wheeze
- Possible increase in sputum, suggestive of an infective cause
- Patients may be hypoxic and, in some cases, experience acute confusion
Management of acute exacerbation of COPD
- Increase the frequency of bronchodilator use and consider nebuliser therapy.
- Give prednisolone 30 mg daily for 5 days.
- oral Antibiotics only if sputum is purulent or there are clinical signs of pneumonia
What are the first-line oral antibiotics for COPD exacerbations?
Amoxicillin
Clarithromycin
Doxycycline
When is admission recommended for a COPD exacerbation?
- Severe breathlessness
- Acute confusion or impaired consciousness
- Cyanosis
- Oxygen saturation < 90% on pulse oximetry
- Social reasons (e.g., inability to cope at home)
- Significant comorbidity (e.g., cardiac disease, insulin-dependent diabetes)
What type of respiratory failure can COPD patients develop during exacerbations?
type 2 respiratory failure (respiratory acidosis)
When is non-invasive ventilation (NIV) used for COPD patients?
BiPaP typically used for COPD with respiratory acidosis (pH 7.25-7.35) despite maximal medical treatment
When should a COPD patient be assessed for long-term oxygen therapy ?
- Very severe airflow obstruction (FEV1 < 30% predicted)
- Cyanosis
- Polycythaemia
- Peripheral oedema
- Raised jugular venous pressure
- Oxygen saturations ≤ 92% on room air
How is assessment for long-term oxygen therapy done in COPD patients?
Assessment is done by measuring arterial blood gases on two occasions, at least 3 weeks apart, in stable COPD patients on optimal management.
What investigation results would indiciate long-term oxygen therapy should be offered to a patient with COPD ?
- pO2 < 7.3 kPa
- pO2 between 7.3 - 8 kPa and one of the following:
Secondary polycythaemia
Peripheral oedema
Pulmonary hypertension
What is the recommended duration of oxygen use for patients receiving long-term oxygen therapy?
Patients should breathe supplementary oxygen for at least 15 hours a day.
What is the target oxygen saturation range for COPD patients at risk of hypercapnia during an exacerbation?
The target oxygen saturation is 88-92%.
* Use a 28% Venturi mask at 4 l/min before blood gas availability.
Why are COPD patients at high risk of hypercapnia
they retain CO2 when treated with O2
What is the target oxygen saturation range for COPD patients with normal pCO2
94-98%
