Week 4: Asthma and COPD Dr Felix Woodhead Consultant Physician

Obstructive Lung Disease Reduced rate of airflow Wheeze Big lungs Asthma COPD Bronchiectasis

Delivery methods Nebulisers Inhalers –Aerosol –Dry powder –Proprietary types

Drugs Bronchodilators

β 2 agonists Short-acting –Salbutamol –Terbutaline Long-acting –Salmeterol –Formoterol

Antimuscarinics Short-acting –ipratropium Long-acting –tiotropium

Steroids Beclomethasone (BCZ) Budesonide Fluticasone Small- particle BCZ

Combined agents Seretide (Purple) –=serevent (salmeterol) + flixotide (fluticasone) –Evohaler (MDI) or accuhaler (DPI) Symbicort –Oxis (formoterol) + pulmicort (budesonide) –Turbohaler (DPI) –SMART regime

COPD

Definition Airflow obstruction (FEV 1 /FVC < 0.7) Usually progressive Not fully reversible Doesn’t change markedly over few months Predominantly caused by cigarette smoking Differentiation from asthma

G LOBAL INITIATIVE FOR O BSTRUCTIVE L UNG D ISEASE FEV 1 ≥ 80%- GOLD stage 1 FEV 1 = 50-79%- GOLD stage 2 FEV 1 = 30-49%- GOLD stage 3 FEV 1 < 30%- GOLD stage 4 Stage 1 needs symptoms (asymp not COPD) Relatively poor correlation between FEV 1 & symptoms

B ODY MASS INDEX O BSTRUCTION D YSPNOEA E XERCISE CAPACITY BMI : <21 or not Obstruction: broadly GOLD cutoffs Dyspnoea: MRC score Exercise tolerance: 6 minute walk test Composite score better than GOLD

Treatment of stable disease NICE 2010

Stop smoking! Assess every time Not asking is a dereliction of duty Only intervention that changes natural history of disease “If you think you’re breathless now, just you wait…” It is NEVER too late to stop smoking Do not diagnose asthma if you think they may have COPD

Inhaled treatment SOB/ex limitation: SABA/SAMA prn Exacs/SOB –LAMA (tiotropium) regardless of FEV 1 –Or LABA if FEV 1 > 50% Combined LABA/ICS if FEV 1 < 50% Still exacs/SOB –LAMA & Combined LABA/ICS

(Home) Nebulisers Consider in patients with distressing symptoms despite adequate inhaled Rx Only continue if beneficial Side effects can occur Takes up time Placebo effect common

Systemic treatment Corticosteroids – avoid Theophyllines –Only after inhaled Rx tried, or not tolerated –Particular care in the elderly –Levels increased by macrolide/fluoroquinolone Mucolytics –Consider in patients with chronic productive cough –Continue only if beneficial

Oxygen therapy Role is to delay death from cor pulmonale The breathlessness paradox –SOB often good pO 2 –Low sats, often not breathless LTOT –pO 2 < 7.3 kPa when stable –pO 2 < 8 kPa and nocturnal hypoxaemia, polycythaemia or cor pulmonale –Needs to be used for at least 15/24 hours Short burst use (cylinders) – little role

Acute exacerbation of COPD

Definition Sustained worsening of symptoms from usual state Beyond daily day-day variation Acute in onset Often associated with –↑ SOB, ↑ cough, ↑ sputum volume, ↑ sputum purulence May require change in treatment Occur due to precarious V/Q in bad lungs caused by often minor stimuli

Exclude Pneumothorax SVT Myocardial infarction Pulmonary oedema Lung cancer PE Pneumonia (NOT ‘infective exacerbation’) No role for ‘CURB’ score in IECOPD (it is not pneumonia)

Management ↑ frequency of inhaled treatment (often nebulised) Steroids for all (30 mg od 7-14/7) Antibiotics if sputum purulent O 2 given –With care, and control –ALWAYS Venturi acutely –Adjusted by SaO 2 not patient/relative/nurse distress –Guided later by ABGs –With NIV if needed

Other issues Like ‘breathlessness’, fear ‘comfort’ Keep calm Do not give opiates/benzos Get senior help if necessary Nebulise on air, using nasal specs for sup O 2 NIV - use early 2.5 mg salbutamol 2° better than 5 mg 4° IV aminophyline can be useful

Non-invasive ventilation For ACUTE ventilatory failure Treats ↓ pH Allows ↑ FiO 2 without ↑ pCO 2 Only suitable if conscious and protecting airway ↑EPAP (PEEP) useful in pulm oedema and obesity NOT poor man’s ITU NO ROLE IN ACUTE ASTHMA/pneumonia

Asthma

Principles Variable airflow obstruction Cough and wheeze Nocturnal features Specific (allergic) triggers Non-specific triggers Eosinophils in airways Responds to steroids

Acute severe asthma PEFR 50-33% RR ≥ 25 HR ≥ 110 Unable to complete sentences But SpO 2 >92% Worse = life-threatening (silent chest, cynanosis, low SpO 2 ) Better = moderate asthma

Treatment Steroids O 2 Nebs driven with O 2 ABG if low sats or drowsy –Normal pCO 2 is a sign of bad prognosis Senior review Increase inhaled treatment/start it. Educate. Inhaler technique Consider IV bronchodilators

Stable asthma Steroids –Inhaled best –Systemic if admission on the cards Step 1: SABA only Step 2: SABA & ICS mcg/day Step 3: add LABA (combined) Step 4: ↑ ICS dose (stop LABA if no benefit) Step 5: help! Montelukast etc, aminophylline Steroids – psychosocial issues?