Introduction

Fewer people are familiar with the concept of Pursed-lip breathing (PLB), which is primarily used to enhance ventilation and alleviate dyspnea. This type of breathing is mostly known to travellers who often travel at high altitudes. It helps people with COPD (Chronic Obstructive Pulmonary Disease) breathe more calmly and feel less out of breath. Several studies have demonstrated that pursed-lip breathing (PLB) affects compartmental lung volumes differently in individuals with COPD.

Not every patient can respond positively to PLB, but noticeable changes in chest wall and compartmental lung volumes are consistently observed among those who do respond. Still, those who respond conclusively have observed decreased end-expiratory lung volume of the abdominal compartment (EELVab), which causes a decrease in air trapping and dynamic hyperinflation, particularly in patients with chronic obstructive pulmonary disease (COPD). Also, a reduction in complete chest wall end-expiratory lung volume (EELV) can increase ventilation and facilitate better respiratory mechanics.PLB also increases the capacity of respiration, which leads to increased end-inspiratory lung volume (EILV)in the ribcage compartment and the total chest wall. This means that, after PLB, responders have higher lung volumes at the end of inspiration, allowing for improved tidal volume and better oxygenation.¹

Earth has three major altitude zones:

• High altitude: 1500 to 3500 meters (about 4,900 to 11,500 feet)
• Very high altitude: 3500 to 5500 meters (11,500 to 18,000 feet)
• Extreme altitude: above 5500 meters (over 18,000 feet)

As we reach very high altitudes, the body needs extra oxygen support to function properly due to the thinner air. For instance, Mount Everest, Earth’s tallest peak, stands at a staggering 29,029 feet above sea level, where oxygen levels are extremely low and every breath becomes challenging.

That is the very extreme point of being on Earth. These altitudes, which are mentioned above are correspond to different levels of low oxygen in the atmosphere. At the peak of Mount Everest, the air pressure decreases to roughly 228 mmHg, whereas at sea level, it's around 760 mmHg. Interestingly, the percentage of oxygen in the air remains the same, but because the pressure is so much lower, there's far less oxygen available with each breath.²

In this article, we are going to discuss PLB and its adaptation at high altitudes. How to adjust yourself when there are lower oxygen levels.

Pathophysiology of high altitude exposure

Let’s now see the pathophysiology of altitude exposure, usually at high altitudes, where the lifestyle is usually hostile due to environmental factors. To maintain the vital functions of the human body, one needs greater behavioural and physiological adaptation. Since high altitudes are far above sea level, people's main challenge is the drop in atmospheric oxygen pressure, making it harder to breathe and get enough oxygen. Also, there are other factors to be taken into consideration, such as extremely low temperatures and humidity, and due to direct sunlight, increased ultraviolet radiation.³

Because of the tough conditions at high altitudes, hypoxia, where the body doesn't get enough oxygen, mainly happens due to the steep drop in atmospheric pressure. As the pressure falls, the amount of oxygen (PO₂) in the air we breathe, in our lungs, and in our blood also drops. As a result, our organs and tissues receive less oxygen.³

Our bodies try to cope by breathing faster (a response called hyperventilation), and the lungs and hemoglobin (which carries oxygen in the blood) work harder to make up for the reduced oxygen. However, how well this system works can vary from person to person and depends on the altitude.

It's also important to remember that certain factors, like using respiratory depressants, pushing the body too hard, getting too cold (hypothermia), or having existing health conditions, can make hypoxia even worse.

To manage this situation, one needs to have physiological adaptation to decrease oxygen pressure in high altitude regions is known as climate acclimatisation.³

Overview of pursed-lip breathing (PLB)

For people with lung conditions that make breathing difficult, the pursed-lip breathing (PLB) technique can be especially helpful. This simple method makes it easier to get air in and out of the lungs, helping them breathe more comfortably. Over time, PLB can also support lung function by keeping the airways open longer and reducing the effort needed to breathe.⁴

It’s commonly used as one of the ways of treatment for chronic obstructive pulmonary disease (COPD), helping patients manage shortness of breath and feel more in control of their breathing.

The potential and breathing ability of individuals with this condition are surprisingly being reduced. It’s a condition where the lungs become overinflated because the person has trouble fully exhaling air. This trapped air makes it harder to breathe and puts extra strain on the lungs. This kind of discomfort can make breathing so hard that it hampers the individual’s quality of life. People with COPD can experience major health benefits from using pursed-lip breathing. It helps them breathe more easily, reduces shortness of breath, and improves overall lung function. The survey of the trusted source study shows that lip breathing has reduced dynamic hyperinflation in people with COPD. As a result, many people with COPD see noticeable improvements in their ability to exercise, their breathing patterns, oxygen levels, and overall stamina. While COPD can’t be reversed, these changes can help slow its progression and make daily life more manageable, which makes respiratory exercises so important; they help improve lung function and make breathing easier. This will make respiration much easier.⁴

Benefits of pursed lip breathing exercise

This breathing exercise can help improve and regulate your breathing in several ways, including

• Reducing the breathing rate to reduce shortness of breath
• By keeping airways open longer, thus alleviating the breathing work
• Pursed-lip breathing enhances circulation by expelling stale air, like carbon dioxide, from the lungs and allowing fresh, oxygenated air to fill them

Not only boosts oxygen levels, but it also promotes relaxation, especially on the side of the lung where the technique is applied by this process. This results in calming the central nervous system by taking regular, deep breaths followed by relaxing the entire body, which will also lower stress and anxiety.⁴

PLB in high-altitude settings

Hypoxic environment challenges

Hypoxia is nothing but a lower level of oxygen, where a hypoxic environment exists mostly at high altitudes, and also occurs in a wide range of aquatic systems, and changes in temporal frequency depend on seasonality and persistence. 

It has many challenges, such as hyperventilation, which means, at high altitudes, the human body naturally responds to lower oxygen by increasing breathing rate. In PLB, the expiration rate slows, and it will increase the volume of air exhaled, which may further enhance its tendency, leading to excessive breathing. Similar to this, Hypocapnia, potential muscle fatigue, and Paradoxical effect can also be seen at high altitudes.

PLB mechanism

So, how does pursed lip breathing work? There are a few steps to be followed. You can practice pursed lip breathing until you get used to it and can do it easily. If you want the benefits of PLB, then it will be more effective when you are focused or relaxed.

Let’s see how to practice it step by step

1. Begin by sitting upright or lying down in a comfortable position. Let your shoulders relax completely
2. Secondly, for 2 seconds, inhale through your nose, feel that the air is moving up to your abdomen, and try to fill your abdomen with air instead of just your lungs
3. In the third step, gently purse your lips as if you’re blowing on hot food, then slowly breathe out. Try to exhale for about twice as long as you inhaled, taking your time. Repeat this process as many times as you need to, at your own pace, to feel more relaxed
4. Feel free to repeat this process as often as you need
5. After the time passes, and as you get used to this breathing exercise, you can increase the inhale and exhale counts from 2 seconds to 4 seconds, and so on

This is how you can practice PLB and get stable oxygen even in high altitudes.⁵

Clinical and field evidence 

In conclusion, this study found that pursed-lip breathing (PLB) helped improve oxygen levels more effectively than normal breathing in people with COPD. It also led to better breathing and heart function. Since PLB is simple to do, costs nothing, and doesn’t involve medicine or equipment, it can play an important role in helping people with COPD feel better and manage their symptoms. Because of these benefits, it should be included in regular rehab programs for COPD patients.⁶

Training patients in pursed-lip breathing (PLB) should be a part of standard nursing care, so that even at home, patients can benefit from it, whether they're supported by family or being followed up by caregivers. Nursing students should also be taught the importance of PLB in lung rehabilitation during their classroom lessons and given practical training on how to include it in patient care. It's a simple technique that can make a real difference in breathing and overall health.⁶

Teaching pursed-lip breathing should be a regular part of nursing care, so that patients can continue to benefit from it even at home. It’s a simple technique that can help improve their breathing and overall comfort.

Pursed-lip breathing (PLB) is a simple technique that helps patients breathe easier and feel more in control. Regular training and support can make it an effective part of daily care and recovery.

Integration into acclimatisation strategies 

This study looked at how climate change strategies are being included in regional development plans, focusing mainly on Europe, especially Greece. The results showed that how well these strategies are integrated varies from one region to another. This depends on things like political support, available resources, and how aware people are of climate issues.

The study found that regions that take advantage of opportunities to include climate change strategies in their planning tend to grow and develop more. This supports what other research has also found, that linking climate action with development plans can bring real benefits. When regions work together and include climate goals in different areas of policy, they tend to see better and more balanced development. Overall, the findings highlight the importance of working in a coordinated way at the regional level to tackle climate change and support long-term growth.⁷

Summary

Pursed-lip breathing (PLB) is a simple, non-medicated breathing technique especially beneficial for people with COPD and those exposed to high altitudes. It helps regulate breathing, reduce shortness of breath, and improve oxygen exchange by slowing down exhalation and keeping airways open longer. At high altitudes, where oxygen levels are low, PLB can support better acclimatization and reduce symptoms of hypoxia. Though not all patients respond equally, PLB is easy to learn and can be integrated into daily care routines, making it a valuable tool for both clinical settings and self-care.