The Use of Noninvasive Positive Pressure Ventilation (NPPV)

Noninvasive positive pressure ventilation (NPPV) is a type of mechanical ventilation that can be used at home to assist with taking a full breath and maintaining adequate oxygen supply in the body, especially while sleeping.

If you have a health condition that causes you to have trouble breathing, such as sleep apnea or chronic obstructive pulmonary disorder (COPD), your healthcare provider may recommend noninvasive ventilation to help support your lung function.

You may already be familiar with noninvasive positive pressure ventilation if you have used a continuous positive airway pressure (CPAP), bilevel positive airway pressure (BiPAP), or auto-adjusting positive airway pressure (APAP) machine.

Purpose and Uses

Noninvasive ventilation can provide you with ventilatory support through your upper airways. NPPV is an alternative to invasive mechanical ventilation (being placed on a ventilator) for people who have chronic respiratory insufficiency or respiratory failure and can no longer breathe adequately on their own.

NPPV is used to manage breathing in the following conditions:

• COPD
• Obstructive sleep apnea
• Obesity hypoventilation syndrome
• Asthma flare-ups
• Cardiogenic pulmonary edema
• Some cases of pneumonia
• Neuromuscular disorders associated with difficulty breathing

Your healthcare provider may recommend NPPV for you if you have COPD and are experiencing an exacerbation that may result in hypercapnic respiratory failure (higher than normal carbon dioxide level in the blood), or if you have moderate to severe sleep apnea (brief interruptions in breathing during sleep).

You may also need NPPV if you have dyspnea (the sensation of shortness of breath), tachypnea (a rapid respiratory rate), and/or hypercarbia with a pH of between 7.25 and 7.35 (normal body pH is between 7.35 to 7.45).

Unlike invasive ventilation, which requires monitoring in the intensive care unit, noninvasive ventilation can frequently be used in the general hospital ward, provided the staff is appropriately trained in its use. And it can be used at home in many situations too.

How It Works

NPPV enhances the breathing process by providing a mixture of air and oxygen from a flow generator through a tightly fitted facial or nasal mask. The positive air pressure helps hold the lungs open, making it easier to get oxygen down into the tiny alveoli (air sacs) where the exchange of oxygen and carbon dioxide take place.

Using this ventilatory support, the alveoli stay slightly inflated after you breathe out, making their expansion easier with your next breath.

Forms of NPPV

There are several forms of noninvasive positive pressure ventilation, including CPAP, BiPAP, and APAP. All three deliver pressurized oxygen through a mask, though they vary in their settings.

Typically associated with sleep apnea treatment, the pressure delivered by PAP machines prevents the throat muscles from collapsing and restricting airflow.

• CPAP: Continuous positive airway pressure is typically used for people who have obstructive sleep apnea. CPAP is set at a single constant level of pressure for both inhalation and exhalation.
• BiPAP: Bilevel positive airway pressure has two settings: one for inhalation and one for exhalation. BiPAP is used more often for people with COPD since it is easier to exhale against a lower pressure, which this system allows for. A healthcare provider will help calibrate the machine and choose your optimal settings.
• APAP: Auto-adjusting positive airway pressure machines can calculate the necessary pressure for an individual's breathing comfort and automatically self-adjust. This "smart" device can be helpful if you have varied breathing patterns during the night, such as during different cycles of REM sleep, or if you move around a lot while sleeping.

Effectiveness

A 2014 research paper published in Lancet found that NPPV improved survival rates in people with COPD who had hypercapnia and respiratory acidosis (slightly lower than normal blood pH). The yearlong, randomized, multi-center, multinational study found that people with COPD who received noninvasive ventilation had a lower risk of death.

Other studies show that NPPV used during acute COPD exacerbations reduces the need for endotracheal intubation and is associated with a lower rate of treatment failure and shorter hospital stays.

In addition, a 2016 study found that long-term NPPV may result in improvements in arterial blood gas (ABG), lung function, and health-related quality of life. In general, these improvements were much better with high-intensity noninvasive ventilation (using the highest possible inspiratory pressure) than with low-intensity NPPV.

Contraindications

NPPV may be contraindicated or would be used with caution if any of the following apply:

• You are medically unstable because of hypotension (low blood pressure), sepsis (a severe generalized infection that can lead to shock), hypoxia (a deficiency in oxygen in the tissues of your body), or another life-threatening systemic illness
• You have a worsening mental status
• You have excessive secretions, which increases the risk of aspiration

A Word From Verywell

NPPV can be beneficial in some circumstances, but it is not always the right solution. Your healthcare provider can determine if you are a candidate for noninvasive ventilation.

That said, NPPV can reduce the need for endotracheal intubation and improve survival rates for some people with COPD. It can improve blood gas values, lung function, and quality of life, particularly with high-flow NPPV. NPPV therapy can also be highly beneficial in the management of sleep apnea.

NPPV is one of many strategies that can improve your quality of life if you have COPD, sleep apnea, or obesity hypoventilation syndrome. Be sure to talk to your healthcare provider about other lifestyle changes that may help.