Overview of Six-Minute Walk Test
The 6-minute walk test (6MWT) is a common measurement tool used to track the fitness level of those living with long-term lung diseases. This simple test helps doctors understand the overall health and exercise capability of those with respiratory and heart conditions. The task is easy to perform and consistent in results. It offers a comprehensive snapshot of how the heart, lungs, and muscles respond to exercise. The best part is, the test doesn’t need any special tools or extensive training for the medical staff who conduct it. It can be done in any doctor’s clinic or hospital and is generally safe and manageable for patients at all disease stages. It is perfect for evaluating everyday activity and exercise abilities.
The 6MWT is especially useful for monitoring and managing chronic obstructive pulmonary disease (COPD), which is a type of lung disease that makes it hard to breathe. It’s also applicable for various other conditions, such as pulmonary arterial hypertension (high blood pressure in the arteries of your lungs) and diffuse parenchymal lung diseases (a group of disorders causing inflammation or scarring in the lungs). In summary, this cost-effective test offers a lot of insightful data which can aid in the treatment of various conditions. The test involves walking as far as possible for 6 minutes in a flat hallway, and the final result is noted down in meters.
Anatomy and Physiology of Six-Minute Walk Test
The way your heart and lungs work together when you exercise is important to a variety of tests. In basic terms, when blood lacking oxygen comes back to the right side of your heart from your veins, it is pushed by a part of the heart called the right ventricle into the artery that leads to your lungs. Here, the blood passes small blood vessels in the lungs where it picks up oxygen and gets rid of carbon dioxide. This exchange of gases happens at little air sacs in the lungs called alveoli.
The blood, now loaded with oxygen, goes back to the left side of your heart. Then this oxygenated blood is sent all around your body to give oxygen to your organs. This whole process is essential for our normal functioning, especially when we do activities that require more energy. Both the nervous system and the parts of your body that allow you to move, like muscles and bones, also play a role in this process. They help your lungs and heart adjust to the changing needs of your body based on how intensely you’re exercising. Essentially, they make sure that the amount of air you breathe in and out matches the amount of blood your heart is pumping.
If any of these parts – the heart, lungs, nervous system, or the body part that helps you move – isn’t working properly, then you may find it harder to exercise.
Why do People Need Six-Minute Walk Test
The 6-Minute Walk Test (6MWT) is a simple test often used by doctors to see how well treatment is working in people with serious heart or lung diseases. This test involves walking for six minutes and measuring how much distance is covered. If someone can’t walk at least 70% of the usual distance before lung surgery, they might have a higher chance of having complications after surgery.
This test is also used to gauge how well someone can exercise and what their outlook might be for the future, depending on the medical condition they have. Because many parts of your body are used during physical activity, the 6MWT can help check conditions that may affect any of these parts. For instance, it’s been used a lot for checking how well people are doing with COPD, a lung disease that causes breathing problems.
It can also be useful for checking other diseases that affect the lungs, like idiopathic pulmonary fibrosis, cystic fibrosis, and sarcoidosis. Similarly, it can be used for heart conditions like heart failure and peripheral artery disease, which can make people very sick and even cause death. It’s often used to check how well people are doing after treatment programs designed to help strengthen the heart.
Moreover, the 6MWT can help doctors see how much disease that affects the nervous system and muscles, such as fibromyalgia, Parkinson’s disease, multiple sclerosis, and spinal muscular atrophy, is affecting someone’s life. And, it can predict how well someone will be able to walk after getting a new knee.
When a Person Should Avoid Six-Minute Walk Test
The 6-minute walk test (6MWT) is a simple way to check a person’s physical fitness. However, there are times when it might not be safe to take the test. The main definite reason why you shouldn’t take the test is if you’ve had a serious heart problem (like unstable angina or a heart attack) in the last 30 days. You should also avoid the test if you’ve fainted without warning, have sudden difficulty breathing or if you have another health problem that might get worse from exercise.
There are also some reasons where it might be safer to postpone the test. If you have seriously high blood pressure that isn’t well controlled, or your heart rate is over 120 beats a minute when you’re resting, it’s generally best to avoid the test. The 6MWT is done at your own pace, which can help keep risks low, but it’s always best to listen to your doctor’s advice. They can judge whether it’s right to go ahead with the test or not.
Equipment used for Six-Minute Walk Test
The necessary equipment for the test includes a device known as a pulse oximeter that measures the amount of oxygen in your blood, a portable oxygen device which can be used by you if needed, a chair, a tested and approved breathlessness scale like the Borg scale, and a stopwatch. There should be at least two small cones available to mark where you need to turn around. A machine called an automated electric defibrillator, used to restart the heart in emergency situations, should also be close at hand. The test should take place in a comfortable space for you that also allows the exact walking distance to be measured.
Who is needed to perform Six-Minute Walk Test?
The Six-Minute Walk Test (6MWT) is carried out by medical staff who are well-trained in the standard procedures for this test. At the very least, these staff members need to know Basic Life Support (BLS), which is a level of medical care used in emergency situations before a patient can reach the hospital. This is to ensure safety during the test. Additionally, if the lab’s main doctor or the doctor who recommended the test thinks it’s necessary, a doctor might be there during the test.
Preparing for Six-Minute Walk Test
Here are some instructions for getting ready for a lung health test, based on advice from recognized international societies for respiratory diseases[1][2]:
Firstly, make sure to wear comfortable clothes, including shoes that are good for walking. If you normally use a device to help you move around, such as a cane or a walker, you should continue to use it.
Keep taking your usual medications as normal. Make sure to rest for at least two hours before the test to make sure you’re ready. If you need to take this test more than once, try to schedule it at the same time of day each time. This helps to keep the testing consistent.
It’s important to know that you should not do any warm-up exercises before the test. Also, if you have a lung function test scheduled on the same day, make sure to complete it at least 15 minutes before the walk test.
How is Six-Minute Walk Test performed
If you need to take a walking test, also known as a 6-minute walk test, here are a few steps the medical staff will guide you through:
Firstly, you will be asked to rest for about 10 minutes before the test begins. This is important to ensure we get accurate measurements.
Next, the test administrator will check your heart rate and oxygen levels. It’s important to keep an eye on these throughout the test because it helps us know how much oxygen your body is using. Keep in mind, the lowest oxygen level might happen before the end of the test.
We’ll then have you rate your level of difficulty in breathing using the Borg scale. The Borg scale is a tool that helps you describe your level of discomfort or pain.
Once these preparations are completed, the staff will set up the lap counter and timer, and you’ll be given clear instructions on what to do during the test.
You’ll then be positioned at the starting line and once the test begins, you will walk on your own without assistance for the duration of the test.
It’s important that you don’t talk with anyone other than the technician during the test. As each minute passes, the technician will tell you how much time is left and encourage you to keep going.
At the end of the test, you’ll be asked to rate how tired you are and how difficult your breathing is using the Borg scale again. The medical staff will check your heart rate and oxygen levels, count the total number of laps you walked, and calculate the total distance you covered.
This information can help your doctor understand your physical condition better and develop the most suitable treatment plan for you.
Possible Complications of Six-Minute Walk Test
When doctors follow the set guidelines and procedures, issues don’t happen often. The design of the test, which allows people to go at their own pace, helps to keep problems minimal. The most common issue that has been reported in medical studies is a drop in oxygen levels below 80%. When this happens, the test usually comes to a stop. Other issues, like chest pain or a very rapid heartbeat, have been reported less often. Most importantly, none of these issues have led to long-term problems.
What Else Should I Know About Six-Minute Walk Test?
The main way to measure how well you’re doing is by checking how far you can walk in 6 minutes – this is called the 6-minute walk distance (6MWD). For healthy people, the usual distance is between a quarter and almost half a mile. It’s important to know this varies by person and can be affected by things like weight and age.
But this walking test isn’t perfect. For example, it can’t tell us why you might be short of breath, have low oxygen levels, or struggle with exercise. And if we notice that your walking distance is lower than normal and we don’t have a clear medical explanation, we’ll need to investigate further. We’ll focus on potential problems with your heart, lungs, or muscles, based on what we know from your medical history.
This walking test is really useful though for certain lung conditions like chronic obstructive pulmonary disease (COPD). It can show us how severe your disease is because it aligns well with quality of life scores, respiratory health, and even survival rates. It can also help us gauge your response to specific treatments. For example, how well you’re doing after surgery to reduce lung volume. The downside is that it’s not really effective for measuring the impact of your medication.
In certain cases, like idiopathic pulmonary fibrosis (an unknown cause of lung scarring) and heart failure, your 6MWD can even predict the likelihood of death. For instance, if you can walk under 250 meters at the start and then lose more than 50 meters within six months, this increases your chances of not surviving. With heart failure, the less you can walk, the higher your risk of being hospitalized or dying. So this test can be very important in cases where your heart or lungs aren’t doing well.
Interestingly, the walking test also aligns with how active patients are who have poor blood flow to the legs—this is better than a treadmill test. In general, if patients with heart or lung disease can improve their 6-minute walking distance by about 46 to 100 feet, this is considered a good sign.
Lastly, diseases like chronic liver disease and kidney failure, which don’t directly relate to exercise, can make you do worse on the walking test, depending on how severe your condition is.