Chronic obstructive pulmonary disease
- 1. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (ACUTE EXACERBATION)
- 2. OVERVIEW • DEFINITION • PATHOGENESIS • COMPLICATIONS • AECOPD • CONSEQUENCES • MANAGEMENT • NIMV • IMV
- 3. COPD • COPD is a chronic, slowly progressive disorder characterised by airflow obstruction • Includes chronic bronchitis and emphysema • FEV <80% predicted & FEV/ VC ratio <70%. ETIOLOGY - Smoking Familial risk Exposure to fuel smoke Alpha 1 antitrypsin def
- 4. PATHOLOGY • Airway wall inflammation • Hypertrophy of mucous secreting glands • Increase in number of goblet cells • Consequent decrease in ciliated cells • Air flow limitation – 1.mechanical obstruction 2.loss of pulmonary elastic recoil • Pulmonary remodelling
- 5. AECOPD • Acute Exaberation of Chronic Obstructive Pulmonary Disease (AECOPD) • Acute change in patients baseline dysnea • Excessive cough and sputum production PRECIPITATING FACTORS • Infectious process • Environmental conditions • Host factors
- 6. SYMPTOMS • Increase in cough • Increase in breathlessness • Increase in sputum volume • Fever • Chest pain • Increase in oxygen requirement
- 7. CONSEQUENCES OF COPD EXACERBATION
- 9. MANAGEMENT • Supplemental oxygen, goal 88-92% • Bronchodilators – Aerosolized albuterol– Ipratropium? • Corticosteroids • Antibiotics • Management of Respiratory Failure – • Non-invasive mechanical ventilation • Invasive Mechanical ventilation
- 10. ANTIBIOTICS • Indications – • Increased dyspnea, • sputum quantity and quality (purulence) • Mechanical ventilation • Organisms – • S.pneumoniae, • H influenza, • M catarrhalis • Risk factors for PsA- • Frequent antibiotics • Severe COPD exacerbations • Prior PsA • Recent health care visit
- 12. RESPIRATORY FAILURE • Type I: Hypoxemic respiratory failure is characterized by pO2 < 60 mmHg with a normal or low pCO2. • Type II: Hypercapnic respiratory failure is characterized by pCO2 > 50 mmHg • Acute form develops within minutes to hours; therefore, pH <7.3 .
- 13. MANAGEMENT OF AECOPD IN CRITICAL CARE • Persistent respiratory distress despite standard management • Inability to maintain oxygen level above 90% despite oxygen therapy by high-flow mask • Persistent hypercapnia • Abnormal blood gas parameters (PaO2< 60 mm of Hg and/or PaCO2>60 mm of Hg) • Alteration of mental status, acute confusion, drowsiness • Increased signs of infection (pyrexia, increased sputum purulence/volume etc) • Significant abnormal changes in chest radiograph • Clinical deterioration
- 14. NON-INVASIVE MECHANICAL VENTILATION INDICATIONS • Accessory muscle use, • short of respiratory failure/agonal breathing • Patient cooperative (exclused agitation, belligerent, coma) • Showing signs of retaining pCO2 1.Assess the pCO2 with the respiratory rate, not what a normal value is (pH 7.1-7.3) 2.RR> 25– • Hypoxemia; P/F ratio < 200
- 15. CONTRAINDICATIONS TO NIMV • Cardiovascular instability • Inability to protect airway:- • Impaired mental status (GCS <8) • Aspiration risks, recent facial surgery or injury • Poor clearance of secretions • Potential for upper airway obstruction:- • Angioedema • Extrinsic compression of the trachea (eg. tumor, hematoma)
- 16. BENEFITS OF NIMV • Symptomatic relief of dyspnea • Correction of gas exchange • Improve lung mechanics • Decrease mortality associated with respiratory failure • Prevent intubation and associated complications:– • Tracheal stenosis, • VAP, • Tracheostomy need, • GI bleed, • DVT, • Myopathy
- 17. INCLUSION CRITERIA • COPD with exacerbation of dyspnea > two days and at least two of the following: • RR>30 • PaO2 < 45 mm • Hg pH < 7.35 after > 10 min on RA EXCLUSION CRITERIA • RR< 12 breaths, sedative drugs within the previous 12 hours • CNS disorder unrelated to hypercapnic encephalopathy or hypoxemia • Cardiac arrest (within the previous five days) • Cardiogenic pulmonary edema • Asthma
- 18. MANAGEMENT • Standard treatment arm:- • O2 via nasal canula up to 5L for target SpO2 > 90% • Antibiotics, bronchodilators, iv steroids or aminophylline • NIV treatment arm:- • Standard treatment above + : • BIPAP for at least 6 hours/day, nasal cannula for at least 2 hours/day • IPAP=20, EPAP=0, flow cycled
- 19. CRITERIA FOR INTUBATION • Major Criteria for intubation: –respiratory arrest, pauses with LOC, gasping, requiring sedation, HR<50 with lethargy, SPB<70 • Minor Criteria for intubation: –RR> 35 and > on admission, pH < 7.3 and < admission, PaO2<45 despite O2, worsening MS
- 21. INVASIVE MECHANICAL VENTILATION • Indications:- • Accessory muscle use • Showing signs of retaining pCO2 :- • Assess the pCO2 with the respiratory rate, not what a normal value is • Does not meet criteria for NIPPV • RR> 35
- 22. INVASIVE MECHANICAL VENTILLATION • Ventilator mode • Volume ventilation in the AC or SIMV mode • Or pressure ventilation—either PRVC or PC • Tidal volume and respiratory rate • Good starting point: 10 ml/kg and 10 to 12 bpm • A small tidal volume (5-8 ml/kg) and 8 to 10 bpm with increased flow rates to allow adequate expiratory time
- 24. VENTILATOR ASSOCIATED LUNG INJURY (VALI)
- 25. PNEUMOTHORAX
- 26. REFERENCES • Davidson’s Principles & Practise of Medicine • Harrison’s Internal Medicine