Chronic Obstructive Pulmonary Disease And Asthma

1. Chronic Obstructive Pulmonary Disease And Asthma ??? 2001-8-20

2. COPD Characterized – airflow obstruction ? by cigarette smoking ? airway hyperresponsiveness and may be partially reversible Caused by 1.) emphysema 2.) chronic bronchitis

3. Emphysema And Chronic Bronchitis Characterize Emphysema -- is anatomically defined as abnormal -- permanent enlargement of the airspaces distal to the terminal bronchioles -- accompanying destruction of the airspaces walls. Chronic bronchitis – is clinically defined as the presence of productive cough for at least 3 months.

4. Asthma Definition Is an inflammatory condition Complex cellular, chemical, and nervous system mediator lead to heightened bronchial responsiveness and episodic, variable and reversible airway obstruction.

5. ICU Evaluation General respiratory history Cough Sputum Hemoptysis Dyspnea Chest tightness or pain Wheezing Exercise tolerance

6. Physical Examination And Vital Signs Inspection Upper respiratory tract ? nasal polyps In COPD Neck vein distension (combined with upper extremity venous distension) may be lung cancer Palpation Percusion Ansculation * Rhochi * Crackles * Wheezing * Stridor Vital signs * Pulses paradoxes * Tahypnea

7. Laboratory Studies Suggestive of COPD And Asthma Chest X-ray * Asthma – hyperinflation with normal or increased vascularity * COPD – blebs and bullae ECG * Hyperinflation cause low- voltage and poor R- wave progression * Cor pulmonale – right axis deviation, R’t ventricular hypertrophy, RBBB ABG * PaO2 < 60 mmHg supplemental O2 therapy * PaCO2 < 40 mmHg Pulmonary function tests (PFTs) measure pulmonary mechanics * Peak expiratory flow measured with and inexpensive peak flowmetor guide the management of asthma * A peak flow less than 50% predicted indicates severe asthma

8. Produce Respiratory Failure In COPD And Asthma Increase resistive and lung elastic loads * upper airway obstruction from tracheal stenos is or edema * bronchospasm * airway edema and secretions * increase functional residual capacity and dynamic airway collapse Increase chest wall load * preexisting kyphoscoliosis or obesity * splinting caused by surgical pain Decrease respiratory muscle strength and endurance Decreased respiratory drive * narcotics * anesthetic agents

9. Treatment COPD And Asthma Agents Anticholinergics Sympathomimetics Corticosteroids Nebulizer versus inhaler Methylxanthines Aneshtetic agents * propofol * ketamine * inhaled sevofluranel

10. Common inhaled anticholinergic drugs

11. Some common inhaled beta-2-adrenergic drugs

12. Common Inhaled Steroids

13. Mechanical Ventilation of COPD And Asthma Volume ventilation – maintains a constant tidal volume during changes in airway resistant and lung compliance Pressive ventilation – improve patient ventilator synchrony and also prevents hyperinflation if auto-PEEP occurs. Inspiratory pressure support ventilation – produce an excessive inspiratory time in the p’t with COPD, because a low flow inspiratory flow rate is required to cycle the ventilator to the expiratory phase.

14. Mechanical Ventilatory Weaning of COPD And Asthma Rapid shallow breathing index – respiratory frequency (breaths/minute) divided by tidal volume in liters * weaning is more likely to be successful if the rapid shallow breathing index is less than 100. Tolerates 30-60 min of spontaneous breathing without signs of fatigue. Extubation should be considered.