Introduction

Acute Respiratory Distress Syndrome (ARDS) is a life-threatening lung condition that causes low levels of oxygen in the blood.¹ Fluid builds up in the alveoli, and a substance called surfactant, which keeps our lungs able to expand, starts to break down, leading to our lungs failing to expand and slowing the transport of oxygen into the bloodstream.¹ Often, one of the components of recovery and treatment of ARDS is pulmonary rehabilitation. Pulmonary rehabilitation (PR) is an education and exercise programme designed for people who have experienced lung disease, particularly involving shortness of breath.² The key to the programme is to help patients understand their condition and how to manage it, and it typically lasts six to eight weeks.² Pulmonary rehabilitation is mainly used for patients managing Chronic obstructive pulmonary disease (COPD); however, it has been used for ARDS, and the outcomes for patients who received this rehabilitation will be the focus of this article.

Overview of ARDS and its effects

Acute Respiratory Distress Syndrome (ARDS) is a type of lung disease that targets alveoli and their production of surfactant, which in turn affects our lungs’ ability to expand correctly when breathing, which in turn leads to a lack of oxygen in our blood.¹ ARDS can develop very suddenly and can worsen rapidly. It can be caused by a variety of factors, such as:

1. Pneumonia³
2. Smoking³
3. Toxins³
4. Near-drowning incidents³
5. Sepsis³
6. Trauma to the lungs³
7. Drug overdose

All of these factors can cause inflammation of the alveoli and then begin to affect our breathing, as previously mentioned. 

The symptoms of ARDS can develop within a few hours and can be very severe and scary to patients.³ Symptoms of ARDS include, but are not limited to: severe shortness of breath, rapid breathing, coughing, chest pain, blue skin colour (cyanosis) and fatigue.⁴ When examined, you may hear crackling sounds in the patient’s chest if listened to with a stethoscope, and you would also find critically low blood oxygen levels.⁵

The low oxygen is what causes the patient to feel the need to breathe rapidly, and it can only be addressed in a hospital setting. Upon someone suffering from ARDS, prompt medical intervention is needed: we need to address the lack of oxygen, prevent complications and treat the underlying cause. In a usual scenario, the patient will be taken to the hospital as oxygen is delivered through a mask or cannula, or sometimes even intubation.⁵

 Most patients will spend time in the ICU as their infection or underlying causes are treated, until their lungs are able to deliver oxygen on their own, but in some extreme cases, advanced measures such as extracorporeal membrane oxygen (ECMO) may need to be used. ECMO is a form of oxygenation where blood is pumped out of the body, oxygenated and then returned to the body to allow the lungs to rest.⁶

ARDS is a serious condition, and it is certainly a medical emergency, but it can be addressed and cured. However, it is also a disease that has some long-term effects that need to be considered.⁷ The long-term effects of ARDS can be organised in three main groups: physical, psychological and effects on quality of life.

The physical long-term effects of ARDS include things such as chronic respiratory issues - for example, continued shortness of breath and reduced lung function⁷. Muscle weakness and fatigue from a prolonged hospital stay are also two physical factors to consider.

Some patients can even develop fibrosis, a condition where the lung tissue stiffens and scars, leading to more chronic breathing problems.⁷

The psychological long-term effects of ARDS can arise as a result of the traumatic experience, as well as a result of the time spent in the ICU. The stress of having an ARDS episode can lead to anxiety and depression,⁷ which can be made worse by the challenges of recovery. Many survivors experience PTSD, which is particularly common in those who experienced long-lasting mechanical ventilation.⁷

Some patients also experience “ICU delirium”,⁷ which refers to reduced cognitive function after the time a patient spends in the ICU. Things such as memory, attention and problem-solving can be severely affected and reduced after a stay in an intensive-care unit. These effects last long after the stay in the hospital, which will have an obvious impact on the patient’s life after their experience with ARDS.

Lastly, many patients suffer a reduction in their quality of life, such as less enjoyment in their hobbies and a lower ability to perform daily tasks.⁷ Some patients also have to receive oxygen therapy even after their discharge from the hospital, which can be a great obstacle for people, especially at the start of their therapy.⁷

These long-term effects cannot be cured with drugs or surgeries, which is why pulmonary rehabilitation is a key component of the recovery process. We will talk more about pulmonary rehabilitation in the next section of this article.

The role of pulmonary rehabilitation

Pulmonary rehabilitation is a programme designed for people who suffer from chronic or acute episodes of lung disease to help them live and manage their condition.⁸ It includes things such as exercise, education and breathing techniques.

A key component of pulmonary rehabilitation is aerobic exercise,⁸ including things such as an exercise stress test to check oxygen levels while exercising, or a six-minute walk test to measure how far you can walk in six minutes and how tired you are afterwards.⁸ During pulmonary rehabilitation, patients will participate in exercise classes and perform these tests to increase their exercise tolerance.

Another component of pulmonary rehabilitation is learning breathing techniques, such as pursed lip breathing or yoga breathing.⁸ This helps patients learn how to control their breathing and avoid feelings of shortness of breath, which can cause anxiety. 

A third component of pulmonary rehabilitation is education, where a health-care professional will give small groups some lessons on how the lungs work, quitting smoking and managing symptoms and flare-ups of their condition.⁸

Sometimes, psychological and nutritional counselling can also be implemented for patients who are eligible for it.

Most patients who are offered pulmonary rehabilitation suffer from COPD, asthma, cystic fibrosis and forms of lung cancer. It can also be offered to patients who have just received a lung transplant or who have suffered from an episode of ARDS.⁸

However, how effective is pulmonary rehabilitation for patients with ARDS?

In a study done on the outcomes of life satisfaction of survivors of ARDS five years post-rehabilitation,⁹ they found that attending the rehabilitation programme had positive outcomes in regards to both the patients’ quality of life and pulmonary function. The patients who went through pulmonary rehabilitation reported high scores of physical and mental satisfaction regarding their quality of life, reporting a better overall quality of life compared to the control group.⁹

In regard to their lung function, patients who attended pulmonary rehabilitation programmes were found to have better total lung capacity, diffusing capacity for carbon monoxide and for FEV1,⁹ which are all important measures of overall lung function. The fact that, in patients who went through pulmonary rehabilitation, these measures were higher on average than in the control group suggests that pulmonary rehabilitation is an important factor in improving the quality of life for people who suffered from ARDS.⁹

By attending pulmonary rehabilitation, patients will have a lower risk of re-hospitalisation,¹⁰ as the education and exercise tolerance built during rehabilitation help reduce the risk of complications such as respiratory infections or other conditions.¹⁰ Pulmonary rehabilitation also teaches patients how to manage comorbidities they may have, such as COPD, and overall, pulmonary rehabilitation is proven to improve survival rates in the long term by helping patients manage chronic symptoms and reducing the impact of the damage done by ARDS.¹⁰

FAQs

How can I access pulmonary rehabilitation?

You will be referred by a healthcare professional - such as your GP or consultant - if they think you may benefit from it.

How do I know if I am having symptoms of ARDS?

Symptoms of ARDS develop very quickly and suddenly. It is often less important to self-diagnose than to call emergency services if you are finding it hard to breathe: any tests and diagnosis can be made later in a hospital.

How long do the benefits of pulmonary rehabilitation last?

Patients will need to keep implementing the exercises and techniques they learned even after the programme is finished. Without doing so, the benefits may diminish within six to twelve months. 

Summary

Acute respiratory distress syndrome is a severe disease that can be very damaging to a patient, targeting multiple systems of the body; hence why a multidisciplinary team approach is essential when it comes to treatment. One of the components of treatment for ARDS is pulmonary rehabilitation. Pulmonary rehabilitation is a programme designed for people who have chronic or acute lung disease, where the goal is to educate and train patients to manage their symptoms and develop an exercise routine. Pulmonary rehabilitation is mainly accessed by patients with COPD and asthma, but it has been proven to be a useful pathway for patients who suffer from ARDS, with studies showing how pulmonary rehabilitation improved both patients’ quality of life and lung function.