COPD Flashcards
What is COPD
Long term deterioration, progressive obstruction with little variability
Bronchitis - obstruction
Emphysema - hyperinflation
What is bronchitis
Wha improves
Definition = Presence of productive cough for 3 months of the year >2 years in a smoker
Likely has COPD
Mucous gland hypertrophy = repeated infection
Increased goblet cells
Inflammation + fibrosis
Obstruction due to airway and alveoli damage
Normal X-Ray just inflammation
Improves if stop smoking
What is emphysema
Inflammation causes increase in size of airspaces due to dilation and destruction of walls
Leads to collapse and trapped air = hyperinflation
Lung tissue for gas exchange destroyed
Increased compliance
Decreased recoil so expiration difficult
What causes lung inflammation in COPD
Smoking and a1AT deficiency
Environment - smoking / pollution / infection
Leads to free radicals
Anti-protease inactivated
Genetics (a1-AT deficiency)
Lungs unable to prevent damage
Leads to inflammation -increased cytokines, protease and oxidative stress
How is A1AT deficiencyy inherited
AR
What does a1AT deficiency do
A1AT protects cells from damage so if deficient cannot protect from damage
Emphysema LL
Cirrhosis
Think in young person with COPD /asthma Sx refractory to Rx
What does smoking do
Increases neutrophils and proteases which cause lung damage
Inactivate anti-proteases
What are the types of emphysema
What can happen to bullae in scar
Centri-acinar - respiratory bronchioles / upper lobe
Pan-acinar - whole acinus
Scar - in periphery, bullae can rupture causing pneumothorax
What are the symptoms of COPD
What happens in severe disease
Suspect in any long term smoker SOB Rapid shallow breath Prolonged wheeze Persistent cough Sputum Recurrent chest infections Minimal variation Resp failure if severe
What are findings on examination
Cyanosis Reduced chest expansion Accessory muscles Barrel chest Hyperinflated chest Tachypnoea Decreased breath sounds Tremor - CO2 retention
What are symptoms RHF and how do you Rx
Hypoxia = Pulmonary hypertension -> RHF if severe which is known as cor-pulmonle Cyanosis Pursed lip on expiration Peripheral oedema Increased JVP Ascites Palpable liver
Rx = LTOT + loop diuretic
How is severity of COPD classed
For DX post bronchodilator FEV1/FVC ratio = <0.7 but severity = FEV1 >80% = mild 50-79 = moderate 30-49 = severe <30 = very severe
What are complications of COPD
Inactivity Depression Cardiac disease - cor pulmonate Loss of muscle mass Pneumothorax
How do you Dx COPD an other investigations
Clinical + spirometry = diagnostic
Spirometry - FVC / FEV1 <70 + PEFR low with minimal bronchodilator reversibility <12%
Other Pulmonary function - Gas transfer is low - TL and RV increased due to hyperinflation CXR Serum a1AT to look for deficiency CT for other Dx ABG - hypoxia + hypercapnia Sputum culture ECG + ECHO - RVH / assess heart BMI - for baseline FBC for anaemia or polythaemia from chronic hypoxia
How do you manage COPD non-pharmacology
Smoking cessation
Exercise
Vaccine - flu + pneumococcal
Mucolytic if chronic cough and other medical Rx failed - carbosistine
Pulmonary rehab to anyone who views as disabled / as soon as feels breathless regular activity as will improve exercise capacity
Nutrition
Physiological support - depression
What is drug therapy for COPD
SABA for mild or SAMA (Ipatropium) = 1st line
LABA (salmeterol) and LAMA (tiatropium) in more severe if no features of asthma
ICS + LABA if features of asthma
Use all therapies as FEV1 decreases
Consider theophylline if others tried or can’t inhale
When do you give long term O2 therapy and when should you assess with 2 ABG
PO2 <7.3 after bronchodilator or nocturnal hypoxaemia Peripheral edema Pulmonary hypertension Polycythaemia NOT if smoking
Assess if FEV1 <49% Sats <92% Cyanosis POlycyhthaemia due to chronic hypoxia Oedema Raised JVP
Why should you be careful when giving O2 in COPD and what is aim
If elevated PaCO2 (Type 2 respiratory failure) then body goes in to hypoxic drive (relies on low O2 not CO2 to stimulate ventilation)
Further oxygen = reduced drive and will lead to retention of CO2
Body won’t respond to high CO2
Eventually resp arrest
pH should not be allowed to fall below <7.25
Requires artificial ventilation
Always give O2 if person with COPD needs as can cure hypercapnia but can’t cure death
Aim sats 88-92 which can be titrated with Venturi
How do you treat a1AT deficiency
No smoking Bronchodilator Chest physio IV A1AT Lung transplant or reduction surgery
What are pink puffer COPD
Increased alveolar ventilation Normal PaO2 and normal or low PaCO2 SOB No cyanosis Type 1 res failure
What are blue puffer COPD
Deceased ventilation Low PaO2 High PaCO2 CYanosed Not breathless Insensitive to Co2
What are asthmatic features on top of COPD
Previous Dx asthma or atopy
High blood IgE
Variation in FEV1
Diurnal variation
When should you consider a Dx
> 35
Symptoms
Past or present smoker
What does spirometry show
PEFR reduced
FEV1 reduced <80%
FVC may be reduced
Ratio <70% even post bronchodilator indicates COPD as non reversible
What does CXR show
Hyperinflated lungs due to chronic air trapping - See more lungs - Low diaphragm Hyperlucent lung field Bullae / holes in the lungs Decreased lung markings Exclude lung cancer
What does FBC show
Polycythaemia
What does PFT show
RV / TLC >30% due to hyperinflation
Decreased gas transfer
What are common causes of chronic cough
TB
Bronchiectasis
Cancer
What do you do for recurrent exacerbations
Azathromycin + prednisolone
Can use doxy if not responding to azthymycin
Only take if purulent sputum / green
What should you do before Azathromyin
Exclude bronchiectasis with CT
Sputum culture to exclude atypical / TB
LFT / ECG as prolong QT
What can you give for recurrent cough
Mucolytic
What do you do to assess if someone needs LTOT
Assess with 2ABG 3 weeks apart
Complications of COPD
Decreased ventilation of alveoli Decreased gas exchange due to loss of parenchyma Hypoxaemia No recoil so takes longer to expire Hyperinflation as air trapped Hypercapnia Chronic increased HCO3 - look at old ABG for baseline Acute exacerbation / infection Polycythaemia due to chronic hypoxia so kidney secrete more EPO Resp failure Cor pulmonale Pneumothorax Lung cancer
What is mild
FEv1 >80% + symptoms
Ratio <70% post bronchidilator as non reversible
What is moderate
FEV1 50-79%
What is severe
30-49%
What is very severe
<30%
What should you aim sats to be in COPD
88-92%
No high flow O2
4l venturi face mask + titrate O2 to get
What is CI in asthma / COPD
BB as bronchospasm
What improves long term outcome
LTOT
Smoking cessation
Lung volume reduction - offer in late stages
What causes acute exacerbation of COPD
Viral = most common
H.influenza = most common
Strep pneumonia
M.catarhalis
What are the symptoms
FEVER + Increase in SOB Cough Wheeze Increase in sputum Hypoxia Confusion
What signs suggest hospital admission
Tachypnoea
Low sats
Hypotension
What investigations when admitted
FBC, U+E, CRP ABG - ECG CXR Blood culture if febrile Sputum microscopy if purulent
Do you give oxygen
Yes if sats low
Hypoxia will kill faster than hypercapnia
Do ABG within 1 hour of O2 therapy
Start 24-28% 4L O2
If critically unwell give with 15l non-rebreathe
How do you treat
Ensure oxygenation -4l venturi aim 88 adjust with ABG
Look for cause - infection / pneumothorax
Increase bronchodilator - SABA/ SAMA
Possible neb - SABA / SAMA / steroid
Prednislone 7 days
AX if infection / sputum purulent (often give just incase)
Diuretic
Anti-mucolytic
What Ax
Amox
Tetracycline
Clarithymycin
If still no response
IV hydrocortisone IV theophylline NIPPV - BiPAP if pH 7.25-7.35 Ventilation and intubation if fails - poor recovery pH <7.25 Regular ABG
Why is BiPAP used
More useful in type 2 as alters pressure
Prevents V/Q mismatch
Complications
SEPSIS
What do you ask in Hx
Usual and recent Rx
Home O2
Smoking status
Exercise capacity
What is DDX
Asthma Pulmonary oedema Obstruction PE Anaphylaxis
What do you do for discharge
GP follow up
Smoking
Vaccines
Indications for NIV
COPD pH 7.25-7.35
Indications for ventilation
pH <7.25
A1T or COPD
Emphysema LL in A1AT
Cholestasis
HCC / cirrhosis
How do you differentiate exacerbation of COPD from pneumonia
CXR - consolidation if pneumonia
What is unusual for COPD to cause
Haemoptysis
Chest pain
DOES NOT cause clubbing - think cancer
What DDX / resp causes of clubbing
Lung cancer Bronchiectasis CF Empyema TB Fibrosis / ILD HF
