From the Guidelines
The treatment of chronic hypercapnic respiratory failure due to chronic obstructive pulmonary disease (COPD) should involve the use of nocturnal noninvasive ventilation (NIV) in addition to usual care, as it has been shown to be effective in improving outcomes. This approach is supported by the American Thoracic Society clinical practice guideline, which suggests the use of nocturnal NIV for patients with chronic stable hypercapnic COPD 1. The guideline recommends that patients undergo screening for obstructive sleep apnea before initiation of long-term NIV, and that NIV be titrated without the need for an in-laboratory overnight polysomnogram (PSG) 1.
Key considerations in the treatment of chronic hypercapnic COPD include:
- The use of NIV with targeted normalization of PaCO2 to improve outcomes 1
- Avoiding the initiation of long-term NIV during an admission for acute-on-chronic hypercapnic respiratory failure, and instead reassessing for NIV at 2-4 weeks after resolution 1
- The importance of regular follow-up and monitoring to adjust NIV settings as needed and to address any complications or side effects 1
In terms of specific treatment protocols, the guideline suggests that NIV be used in addition to usual care, which may include medications such as bronchodilators and corticosteroids, as well as pulmonary rehabilitation and lifestyle modifications 1. The goal of treatment should be to improve symptoms, reduce morbidity and mortality, and enhance quality of life, and NIV has been shown to be an effective component of this approach 1.
From the Research
Treatment Options for Chronic Hypercapnia
- Noninvasive ventilation (NIV) is a widely used technique to remove carbon dioxide and has been investigated in several studies for its role in treating chronic hypercapnia in COPD patients 2, 3, 4.
- Carbonic anhydrase inhibitors, such as acetazolamide, may stimulate breathing and have been studied as a potential treatment for hypercapnic ventilatory failure in COPD patients, with some studies showing a small increase in arterial oxygen and a fall in carbon dioxide levels 5.
- Nasal high-flow (NHF) ventilation may be an alternative to NIV in COPD patients with stable chronic hypercapnia, with studies showing a positive impact on blood gases and respiratory scores 3.
Management of Hypercapnia
- Optimizing the use of low tidal volume mechanical ventilation to enhance carbon dioxide elimination is a possible treatment option for hypercapnia 6.
- Techniques to reduce dead space ventilation and physiological dead space, use of buffers, airway pressure release ventilation, and prone position ventilation may also be used to manage hypercapnia 6.
- Extracorporeal techniques, such as low volume venovenous extracorporeal devices, may be used in patients where hypercapnic acidosis cannot be managed with lung protective mechanical ventilation 6.
Efficacy of Noninvasive Ventilation
- NIV has been shown to decrease the risk of mortality and need for endotracheal intubation in patients with acute hypercapnic respiratory failure due to exacerbation of COPD 4.
- NIV use is also associated with reduced length of hospital stay, reduced incidence of complications, and improvement in arterial blood gases 4.
- However, treatment intolerance was significantly greater in the NIV group than in the usual care group, and there was a non-significant trend towards reduction in dyspnea with NIV compared with usual care 4.