Asthma & COPD Flashcards
What is asthma?
Reversible small airway obstruction due to bronchial hypersensitivity
Characterised by bronchospasm + inflammation + oedema
What are the precipitants of asthma?
Cold air Smoking Exercise Damp Allergens Drugs (Aspirin, NSAIDs, BB)
How does asthma present?
Nocturnal cough Recurrent rhinitis Exertional dyspnoea Reflux Diurnal variation Sx of atopy
How does an acute asthma attack present?
Acute dyspnoea Hyperinflated chest Polyphonic wheeze ↑Mucous production ↑HR + ↑RR (hyperventilation) ↑Resonance on Percussion
How is asthma investigated?
PEFR
Spirometry
Fractional exhaled NO test (>17yo)
Histamine/Methacholine direct bronchial challenge test
How is asthma diagnosed?
Sx PLUS: -FeNO >40 OR -FEV1/FVC <70% OR -FeNO 25-30 AND +ve bronchodilator reversibility test OR - +ve bronchodilator reversibility test >200ml or 12%
How is spirometry used when investigating asthma?
FEV1/FVC <70% (<0.7)
Do bronchodilator reversibility test (give SABA)
How is PEFR used when investigating asthma?
If uncertain ∆ post-FeNO/Spirometry/Reversibility
Monitor peak flow for 2-4w
Compare w/predicted peak flow
Monitor for diurnal variation
How is asthma managed in an adult?
1) SABA (Salbutamol)
2) SABA + ICS (Beclamethasone BD)
3) SABA + ICS + LRTA (Montelukast) review in 4-8w
4) SABA + ICS + LABA (Salmeterol)- Stop LRTA
5) SABA + MART (ICS + LABA Combi inhaler) ± LTRA- Stop LABA
6) ↑Dose to mod ICS
7) ↑Dose to high ICS OR trial LAMA/Theophylline/Specialist
In managing asthma when should moving up the ‘ladder’ be considered?
Using salbutamol >3 doses/week
How is acute asthma treated?
OH SHIT ME!
O: O2 if <94%
S: Salbutamol news 5mg back to back every 20mins x3 doses
H: Hydrocortisone IV 100mg
I: Ipratropium nebs 500mcg 4-6hourly
T: Theophylline IV
M: 2g MgSO4 in 100mls NaCl IV over 20mins
E: Erm HELP!!- CPAP
O2 driven nebs- 6L
Give 1-4 at the same time
What bronchodilator reversibility levels would suggest someone has asthma?
A 200ml improvement in FEV1 or 12% in response to:
- 400mcg salbutamol
- 6w trial of ICS (beclometasone 200mcg bd)
How much salbutamol should be advised to give to a patient having an asthma attack (where nebs can’t yet be given)?
4 puffs of salbutamol
then
2puffs every 2 mins-max 10 puffs
When someone is sent home post-asthma attack what meds need to be given?
If PEFR <50% initially: Prednisolone 40mg 5days
Can be stopped abruptly if continuing ICS
Salbutamol weaning: 6 puffs QDS, 4 puffs QDS
What are the differences in: FEV1 FVC FEV1/FVC in obstructive & restrictive lung diseases?
O: ↓FVC, ↓↓FEV1, ↓FEV1/FVC
R: ↓↓FVC, ↓FEV1, ↑FEV1/FVC
What are the common obstructive lung diseases?
Asthma
COPD
Bronchiectasis
Bronchiolitis obliterans
What are the common restrictive lung diseases?
Pulmonary fibrosis Asbestosis Sarcoidosis NM disorders ARDS
In an asthma attack, what constitutes a moderate attack?
↑Sx
PEFR 50-70%
In an asthma attack, what constitutes a severe attack?
PEFR 33-50%
Inability to complete sentences
↑RR ≥ 25
↑HR >110
In an asthma attack, what constitutes a life threatening attack?
PEFR <33% SpO2 <92% PaO2 <8 Normal PaCO2 Cyanosis HypoT Silent chest Confusion/exhaustion Arrhythmia
In an asthma attack, what constitutes a near fatal attack?
PaCO2 >6- requires mechanical ventilation
What is COPD?
Progressive, irreversible, obstructive airway disease
2types: Chronic bronchitis, Emphysema
How are chronic bronchitis and emphysema differentiated?
CB: Cough >3m for 2 consecutive years, ↓alveolar ventilation + undamaged capillary bed → ↑residual lung volume + hypoventilate (→ T2 RF +cyanosis)
E: Enlarged alveolar airspace, ↑alveolar ventilation + damaged capillary bed → muscle waste + hyperventilate (→ T1 RF)
What are the 2 types and causes of emphysema?
Centrilobular: Smoking
Panlobular: α1-Antitrypsin deficient due to Cirrhosis
Which type of COPD relies on the hypoxic drive for respiratory effort?
Chronic bronchitis patients
Who should be worked up for ?COPD?
> 35yo current or ex-smoker w/chronic cough
What are the signs of COPD on spirometry?
FVC <0.7 FEV1/FVC <70% FEV1 varies TLC↑ RV↑
What are the different stages of COPD?
Mild/S1: FEV1 >80%, FVC <0.7 post-bronch
Mod/S2: FEV1 50-79%, FVC <0.7
Severe/S3: FEV1 30-49%, FVC <0.7
V.Severe/S4: FEV1 <30%, FVC <0.7
When in COPD is spirometry CI?
Recent MI/Stroke/Surgery
Unstable angina
Pneumothorax
TB
What investigations should be done when initially diagnosing COPD?
Spirometry
CXR
FBC ↑PCV (assess polycythaemia)
BMI (work out BODE Index)
What is the BODE Index?
4yr Survival predictor B: BMI (>21/ <21) O: Obstruction (FEV1 post-bronch) D: Dyspnoea scale E: Exercise capacity (6min walk)
0 to 2 Points: 80%
3 to 4 Points: 67%
5 to 6 Points: 57%
7 to 10 Points: 18%
What will be seen on an ABG of someone with emphysema & chronic bronchitis?
E: ↓PaO2
CB: ↓PaO2 ↑PaCO2
How is stable COPD managed?
1) SABA (Salbutamol)/ SAMA (Ipratropium)
2) FEV1 >50% = LABA (Salmeterol)/ LAMA (Tiotropium)
2) FEV1 <50% = LABA + ICS (Beclomethasone/Fostair) OR LAMA ALONE
3) LABA + ICS + LAMA
4) Theophylline + Salbutamol
Productive cough: Mucolytic (Carbocristine)
What are the indications for BiPAP?
pH <7.3 PCO2 >6 Resp weakness Chest wall deformity Obesity Hypoventilation
What is the criteria for LTOT in COPD?
pH <7.3 when stable AND one of:
- Polycythaemia
- Nocturnal hypoxaemia sats <90%
- Peripheral oedema
- Pulmonary HTN
What are the signs of COPD on CXR?
Hyperexpanded- >6 ant ribs Large central pulmonary arteries Bullae Peripheral vascular markings Flattened hemi-diaphragm
Other than medications, in COPD what other treatments are available?
Vaccines: Annual flu & Pneumococcal (↑↑ risk of Hib)
Pulmonary rehab
How is an acute exacerbation of COPD managed?
COSI CAR:
CO: Controlled O2- 28% venturi
S: Salbutamol 5mg nebs w/O2 OR air
I: Ipratropium 500mcg
C: CXR- ALL & Corticosteroids IV hydrocortisone 200mg
A: IV Abx if from infection (Clarith or Doxy)
R: Resp support- BiPAP if CO2 rising
When someone is sent home post-COPD exacerbation what meds need to be given?
Prednisolone 30mg 7d
Abx: IF Hx of fever/purulent sputum = Amoxicillin
How can individuals feeling unwell with COPD avoid hospital?
Use rescue packs:
↑ Salbutamol use to control Sx
PO Steroids
Abx if purulent sputum
What are the complications of COPD?
Cor Pulmonale
Over-oxygenation
How does Cor Pulmonale occur?
COPD destroys cap bed
Leads to ↑pulm pressure + hypoxia = reflex pulmonary vasoC + ↑vasc resistance
↑Pul pressure past threshold → R ventricular failure = HF
How does Cor Pulmonale present?
Bronchiectasis Peripheral oedema Dyspnoea Nausea ↑ JVP
How is O2 titrated in COPD exacerbations?
CRITICALLY ILL: 15L/min reservoir mask
SERIOUSLY ILL: 2-6L/min via nasal cannula or 5-10L/min via mask, Sats <85% = 15L reservoir
MILD: 28% venturi recheck ABG at 30-60mins titre up if needed
