JC WCS 17 COPD & SMOKING ABSTINENCE

Prof WK Lam

Medicine

Tue 12-11-02

DEFINITION
  1. CB sputum: whitish mucoid
  2. Bronchiectasis: purulent (yellow/ green) ± haemoptysis

EPIDEMIOLOGY

  1. Cig smoking (commonest cause)
  2. Atmospheric pollution (incl. occupational exposure)
  3. Genetic: eg. a 1 anti-trypsin deficiency - rare, EM <40yo, cannot handle any insult assoc. with chronic cig smoking \ massive alveolar damage

CLINICAL FEATURES

PATHOPHYSIOLOGY
  1. Mucus gland hypertrophy (1/3 to 1/2 ® ­ sputum produc'n + cough)
  2. Goblet cell hyperplasia
  3. Inflam cell infiltrate
  4. M hypertrophy
  1. Perm abn dilatation of GE space (ie. Resp bronchioles + alv)
  2. Destruction of alv septa ® ¯ elastic recoil

INVESTIGATIONS
  1. Hyperinflation + other EM features
    1. Low, flat, horiz diaphragm
    2. Heart elongated (long, narrow) b/c lung H-inflated + pulling down heart + lungs
    3. ­ Pul shadow (b/c pul HT)
    4. ­ space retrosternal + retrocardiac (severe H-inflation) seen on lat CXR
    5. ­ Lung size
  1. Cor pulmonale - features of pul HT
  2. Infection - prone to pneumonia
  3. Pneumothorax - all Pt with af obstruction (COPD, asthma)
  4. Coexisting ca lung - most these Pt's chronic smokers (® pleural effusion)
  1. Irreversible af obstruction
  2. Air trapping
  3. Hyperinflation
  4. ¯ Diffusing capacity (EM)
  1. Hb - polycythaemia (response to chronic hypoxaemia ® may make cyanosis worse, ­ prone to pul embolism b/c ­ Hb + ¯ PA due to SOB)
  2. WBC - infection
  1. Type I RF (¯ PaO2 < 8kPa)
  2. Type II RF (¯ PaO2 + ­ PaCO2)
  1. B/c many Pt's with acute exac due to infection
  2. Microbiol studies for purulent sputum
  3. If haemoptysis + CXR suggestive ® AFB smear + cytology
  1. Cor pulmonale
  2. Assoc CHD (elderly, male, chronic smoker)

MANAGEMENT

General Principles
  1. Anticholinergics - ipratropium (inhaled): blocks bronchoconstrictive effects of Ach primarily in large aw
  2. b 2-agonists - salbutamol (Ventolin/ albuterol), terbutaline (Bricanyl (inhaled): (+) adrenergic rec ® relax'n of bronchial SM
  3. Combination: eg. combivent (ipratropium bromide + ventolin)
  4. Theophyllines - theodur (IV or oral only)
  1. When FEV1 ­ by 12% after inhaled bronchodilators
  2. But if COPD use bronchodil and ­ FEV1 8-9%, may still help Pt even though not reversible

Acute Management
  1. Strep pneum, H influenzae, M catarrhalis
  2. Routine culture not cost effective
  3. Choice ABX clinical ® local bacteria + resistance patterns
  4. Indicated when ³ 2 of:
    1. ­ Dyspnoea
    2. ­ Sputum vol
    3. ­ Sputum purulence
  1. Inexpensive ABX: amoxycillin, macrolide, deoxycycline (not as good)
  1. Type I: hypoxaemia (Tx with controlled O2)
  2. Type II: hypoxaemia + hypercapnia (relieve ­ CO2 with H-vent'n, but COPD cannot H-vent \ vent'n help) \ need arterial blood gas to determine Tx type
  3. NNIPPV (nasal non-invasive positive pressure ventilation
    1. No intubation
    2. Mask: prevent air leakage
    3. ¯ Intubation need
    4. ­ GE
    5. ¯ Hosp stay + Mortality
  1. Acute: O2 to relieve hypoxaemia (Pt blue)
  2. Chronic: VC of pul BV due to hypoxaemia (\ O2 relieves 1o cause)

LT Management
  1. Use O2 in controlled manner to achieve target PaO2
  2. 8kPa (60mmHg) (SaO2 90%) without significant CO2 retention + acidosis
  3. Modes
    1. Nasal cannulae: 1L/min ® 3% FIO2)
    2. Venturi masks: 24%, 28%
  1. Monitor
    1. Clinical: Pt cyanotic?
    2. Pulse ox: non-invasive (clip finger), continuous
    3. Blood gases 30 min after D FIO2 or if D condition (invasive, arterial blood, Pt hold wound for 25 min, not continuous unless cannula)
  1. Physio
  2. M prg
  3. Nutrition
  4. Psych therapy
  5. Education
  6. Ventilation support
  7. Home care

End-Stage COPD

COMPLICATIONS
  1. Pneumothorax
  2. ­ af obstruction
  3. Infection
  4. Resp failure
  1. CHD - elderly, male, smoker
  2. Ca lung
  3. Pul thromboembolism - polycythaemia, immobility

SMOKING CESSATION

  • Reasons why ppl smoke
  1. Overlearnt habit
  2. Assoc. with 2o reinforcement: intertwined with daily events (fun, grown-up, male image, boredom)
  3. Routine
  4. Craving
  5. Stress
  6. Social-peer pressure
  7. Relaxation
  1. Nicotine = stimulant + addictive
  2. Risk of ca lung will never become that of non-smoker (but "approaches" that after 10y of quitting)
  3. Smokerlyser: measure [CO] in exhaled ear to see if Pt has really quit
  4. Nicotine gum
  1. Need personal reason
  2. Save $
  3. More acceptable socially
  4. Not harm others
  5. Improve health - yourself + family
  6. Smell fresher - clothes + home
  7. ­ smell/ taste
  8. Fire hazards
  1. Smoking is enjoyable or simply to relieve WD symptoms
  2. Helps cope under pressure
  3. Put on wt if abstains
  4. Someone smoked until 90yo - LUCKY. 1/4 die from smoking-rel dis
  5. Damage will be done by now, no point quitting now (not true)
  1. 50% Pt's found it easier than originally thought
  2. Craving
  3. Coughing
  4. Hunger + wt gain
  5. Bowel disturbance
  6. Sleep disturbance
  7. Dizziness + paraesthesia
  8. Mood swings, lack of concentration, irritability
  1. Give up for someone or with someone
  2. Fam and friend support
  3. Cig intake
  4. WD reaction
  5. Time to first cig of day better indicator of dependence
  6. Smoker in family
  7. Personality and will-power
  8. Cognitive beliefs - about health risks, self-efficacy, self-prediction of success
  9. Psych well-being: 20% of smokers have depressive symptoms

Note: success rate only 20% even with good support