chronic%20obstructive%20pulmonary%20disease
CHRONIC OBSTRUCTIVE PULMONARY DISEASE

Chronic obstructive pulmonary disease (COPD) is an inflammatory respiratory disease characterized by reversible airflow limitation.

The patient usually have chronic cough, sputum production or dyspnea with or without history of risk factors for the disease.

The chronic airflow limitation is caused by a combination of small airways disease and parenchymal destruction.

It is a preventable & treatable disease.

Supportive Therapy

O2 Therapy 
Long-term Management

  • Long-term administration of O2 (>15 hours/day) increases survival in patients with chronic respiratory failure
    • O2 therapy may also benefit hemodynamics, hematologic characteristics, exercise capacity, lung mechanics & mental state
  • Given to patients with stage IV (very severe) COPD with the following:
    • PaO2 ≤55 mmHg (7.3 kPa) or SaO2 ≤88% with or without hypercapnia confirmed 2x over a 3-week period or
    • PaO2 between 55-60 mmHg (7.3-8 kPa) or SaO2 88%, if there is evidence of pulmonary hypertension, peripheral edema suggesting congestive heart failure, or polycythemia
  • Aim is to increase baseline PaO2 to ≥60 mmHg (8 kPa) &/or produce SaO2 ≥90%, thus preserving vital organ function
  • Inappropriate use of O2 therapy may result in respiratory depression
  • Patients must be given adequate instructions about the source of O2 to be used, method of delivery, duration of use, & flow rates to be used for different levels of physical activity (eg at rest, during exercise, during sleep)
  • Patients should be warned to discontinue smoking when prescribed O2

Hospital Management

  • Cornerstone of hospital treatment for COPD exacerbations & in patients with chronic respiratory failure
  • Goal of O2 therapy is to maintain SaO2 >90% without precipitating respiratory acidosis or worsening hypercapnia
  • SaO2 >93% is not advisable as patient may become drowsy from CO2 retention
  • Once O2 is started, ABG must be checked after 30-60 minutes to ensure adequate oxygenation without CO2 retention or acidosis
    • Blood gases must be monitored regularly depending on response to treatment

Hydration & Nutrition

  • Fluid balance & nutritional status must be monitored & maintained at an optimal level

Mechanical Ventilation
Non-invasive Mechanical Ventilation (NIV)

  • First-line treatment of acute hypercapnic respiratory failure in COPD exacerbation in patients without contraindications
  • Usually employed in patients with ≥1 of the following: severe dyspnea with signs of respiratory muscle fatigue, &/or increased work of breathing (eg use of accessory muscles, intercostal space retraction), acidosis (pH <7.35 &/or PaCO>6.0 kPa, 45 mmHg), persistent hypoxemia despite supplemental O2 therapy
  • Has been shown to increase pH, reduce PaCO2, reduce severity of breathlessness in the 1st 4 hours of treatment & decrease length of hospital stay, mortality & intubation rate

Invasive Mechanical Ventilation

  • Utilized in patients with the following:
    • With contraindications to non-invasive mechanical ventilation or failed non-invasive mechanical ventilation 
    • Life-threatening hypoxemia unresponsive to NIV 
    • Severe dyspnea
    • Impending respiratory or cardiac failure
    • Apnea with loss of consciousness
    • Gasping for air
    • Altered mental status in spite of aggressive pharmacotherapy
    • Severe hemodynamic compromise unresponsive to hydration & medications
    • Massive aspiration
    • Unable to suction resp secretions
    • <50 bpm PR with loss of consciousness
    • Severe ventricular arrhythmias
    • Psychomotor agitation unresponsive to sedatives
  • There is a major risk of ventilator-associated pneumonia, barotrauma & failure to wean
Digital Edition
Asia's trusted medical magazine for healthcare professionals. Get your MIMS Respirology - Malaysia digital copy today!
DOWNLOAD
Editor's Recommendations
Most Read Articles
Pearl Toh, 08 Jun 2016
Middle East Respiratory Syndrome (MERS) patients have more severe illness and a higher mortality rate than non-MERS severe acute respiratory infection (SARI) patients, according to a study presented at the recent American Thoracic Society (ATS) International Conference 2016 held in San Francisco, California, US.
Rachel Soon, 04 Aug 2017

Investment in health crisis response systems during non-pandemic periods is crucial to combating the next inevitable flu pandemic, according to a government representative.

30 Apr 2016
New drug applications approved by US FDA as of 16 - 30 Apr 2016 which includes New Molecular Entities (NMEs) and new biologics. It does not include Tentative Approvals. Supplemental approvals may have occurred since the original approval date.
15 Jan 2017
New drug applications approved by US FDA as of 1 - 15 January 2017 which includes New Molecular Entities (NMEs) and new biologics. It does not include Tentative Approvals. Supplemental approvals may have occurred since the original approval date.