Chronic Obstructive Pulmonary Disease And Asthma

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Chronic Obstructive Pulmonary Disease And Asthma

• ???
• 2001-8-20

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

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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.

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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.

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ICU Evaluation

• General respiratory history
• Cough
• Sputum
• Hemoptysis
• Dyspnea
• Chest tightness or pain
• Wheezing
• Exercise tolerance

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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

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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, Rt
  ventricular hypertrophy, RBBB

• ABG
• PaO2 lt 60 mmHg supplemental O2 therapy
• PaCO2 lt 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

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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

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Treatment COPD And Asthma Agents

• Anticholinergics
• Sympathomimetics
• Corticosteroids
• Nebulizer versus inhaler
• Methylxanthines
• Aneshtetic agents
• propofol
• ketamine
• inhaled sevofluranel

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Common inhaled anticholinergic drugs
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Some common inhaled beta-2-adrenergic drugs
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Common Inhaled Steroids
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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 pt
  with COPD, because a low flow inspiratory flow
  rate is required to cycle the ventilator to the
  expiratory phase.

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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.