Ventilation in chronic obstructive pulmonary disease (COPD)

In mechanical ventilation, a machine (ventilator) moves air into the lungs. This is sometimes used for chronic obstructive pulmonary disease (COPD) to either help your breathing efforts or to breathe for you. Mechanical ventilation can be used as short-term therapy when you experience a sudden and severe shortness of breath (COPD exacerbation) or, rarely, as long-term therapy in your home or a long-term care facility. Mechanical ventilation can be invasive or noninvasive.

Invasive ventilation

In invasive mechanical ventilation, a breathing tube is inserted into your windpipe and a machine forces air into the lungs. Although this can be lifesaving in life-threatening COPD exacerbations, it is not always successful in this situation. Consider discussing your feelings about using this treatment with your health professional and family before the situation arises.

Consider that:

• You generally need calming (sedative) and pain medications. You may occasionally need drugs to paralyze the respiratory muscles.
• The medications make it difficult for you to communicate with caregivers and can have harmful effects on your blood pressure and bowel function.
• The treatment can increase the risk of a collapsed lung (pneumothorax) in which there is air in the chest that is outside of the lung.
• Because the breathing tube is inserted directly into the windpipe, it may interfere with an important defense mechanism that helps to prevent pneumonia. This results in an increased risk of ventilator-associated pneumonia, which is more likely to be caused by antibiotic-resistant bacteria and can be difficult to treat. There is less risk of developing this type of pneumonia when noninvasive ventilation is used.
• Although rare, breathing tubes can cause significant injury to either the vocal cords or the windpipe.

Noninvasive ventilation

In noninvasive positive-pressure ventilation (NPPV), air is pushed into your lungs to help you breathe through a mask that covers either the nose, or the nose and mouth. NPPV generally is recommended for severe COPD exacerbations and acute respiratory failure, in which breathing becomes more difficult and may reach the point where it becomes nearly impossible to breath without ventilation.^{1, 2}

Research reviews note that using NPPV along with standard medical therapy for severe COPD exacerbations and acute respiratory failure resulted in fewer days in the hospital, a higher in-hospital survival rate, and less need for a tube being inserted through the mouth or nose and into the windpipe (endotracheal intubation) compared to medical treatment alone.^{1, 2} However, people with mild exacerbations did not benefit from NPPV.¹

NPPV is sometimes recommended for those with severe stable COPD. Research examining NPPV in this setting has shown conflicting results, with some research indicating a possible positive benefit and other research showing no benefit.³ More study needs to be done.

NPPV should not be used for everyone with acute respiratory failure from COPD. Although there are clear advantages to the use of NPPV, this therapy is not appropriate for all people with this condition. People who have very low blood pressure, are not breathing on their own, and are not fully able to think and interact with caregivers are not considered appropriate candidates for NPPV. In these cases, it is generally safer to use invasive mechanical ventilation.

Citations

1. Keenan SP, et al. (2003). Which patients with acute exacerbations of chronic obstructive pulmonary disease benefit from noninvasive positive-pressure ventilation? Annals of Internal Medicine, 138: 861–870.

2. Ram FSF, et al. (2005). Non-invasive positive pressure ventilation for treatment of respiratory failure due to exacerbations of chronic obstructive pulmonary disease. Cochrane Database of Systematic Reviews (2). Oxford: Update Software.

3. Wijkstra PJ, et al. (2005). Nocturnal non-invasive positive pressure ventilation for stable chronic obstructive disease. Cochrane Database of Systematic Reviews (2). Oxford: Update Software.