Restrictive Lung Diseases (Pulmonary Fibrosis, Neuromuscular Disorders)

This lesson is going to quickly cover the basics of restrictive lung diseases. There are quite a few things that cause this, so we want you to just understand the basics and the things you might need to know on the NCLEX and as a new grad.

First I want to make sure you get the difference between obstructive and restrictive lung diseases. Obstructive lung diseases obstruct the flow of air into and out of the alveoli. So here’s the air passage down to the alveoli and it’s somehow blocked or limited. We’ve already talked about two of these, can you think of what they are? What diseases constrict these airways? COPD and Asthma. Both of those are considered obstructive lung diseases and they obstruct flow into and out of the alveoli. Now, restrictive is a little different. The air passages are all open just fine, but the lungs themselves are restricted from expanding within the thoracic cavity. That means the total lung volume or capacity will decrease. I could physically get the air in, if only my lungs would expand – but they won’t. Since they won’t expand, I can’t get the air in and gas exchange is going to be severely limited. These patients will also struggle to get an effective cough. Why? Well, think about how you cough – you take a deep breath in and then force it out hard and fast. If they can’t get a deep breath in, they will struggle to get those secretions out as well.

There are two classes of restrictive lung diseases. The first is intrinsic – that means there is a problem with the lung tissue itself. Intrinsic means from within. Usually this involves some sort of significant damage or scarring of the tissue that makes it lose its elasticity. If it isn’t elastic it can’t expand and contract – therefore the total lung capacity will be less. The most common example of this is Pulmonary Fibrosis. This is a progressive, terminal lung disease with no cure that has a mortality rate higher than most cancers. Other examples would be sarcoidosis or toxic exposures like asbestos. The second class is extrinsic – this means that something outside of the lungs is causing them to not be able to expand. Extrinsic means from the outside. Think of it like your lungs being in a wooden box – they can only expand as much as the box will let them. Normally they’re in more of a rubber box that stretches and contracts. If the box gets stiff, the lungs can’t expand normally. The most common example here is neuromuscular disorders like ALS (or Lou Gehrig’s disease), muscular dystrophy, and quadriplegia. The muscles of the thorax and diaphragm can’t contract and relax properly, so the thorax becomes a stiff wooden box. Like I said before, if the lungs can’t expand – gas exchange and coughing become nearly impossible.

So what will our assessment look like? Well you may have noticed that the diseases that cause restrictive lung disease tend to be progressive and usually don’t have a cure. So the severity of symptoms will depend on how much their disease has progressed. They’ll likely have adventitious breath sounds – they might start out with crackles as their ability to cough is limited, and then they’ll become more and more diminished as their lung capacity decreases. You’ll see some accessory muscle use and shallow breathing, and because they have a weak cough you’ll see them struggling to get secretions out. Many times they require suctioning or assisted coughing. They’ll have poor gas exchange, which means a high CO2 and a low O2, and because of the chronic hypoxia we’ll see clubbing of their fingers. These diseases are typically not localized in the lung, so on the chest x-ray you’ll see infiltrates or consolidation bilaterally, and you may also see their lungs are smaller than normal. You can see all the fluid that has built up in their lungs here and how the bottom of their lungs really isn’t expanding at all. Now because these patients have a lot of secretions building up, they are at high-risk for lung infections. In fact, that’s one of the most common causes of death in these patients – so protecting their airway becomes one of our top priorities.

So what will our assessment look like? Well you may have noticed that the diseases that cause restrictive lung disease tend to be progressive and usually don’t have a cure. So the severity of symptoms will depend on how much their disease has progressed. They’ll likely have adventitious breath sounds – they might start out with crackles as their ability to cough is limited, and then they’ll become more and more diminished as their lung capacity decreases. You’ll see some accessory muscle use and shallow breathing, and because they have a weak cough you’ll see them struggling to get secretions out. Many times they require suctioning or assisted coughing. They’ll have poor gas exchange, which means a high CO2 and a low O2, and because of the chronic hypoxia we’ll see clubbing of their fingers. These diseases are typically not localized in the lung, so on the chest x-ray you’ll see infiltrates or consolidation bilaterally, and you may also see their lungs are smaller than normal. You can see all the fluid that has built up in their lungs here and how the bottom of their lungs really isn’t expanding at all. Now because these patients have a lot of secretions building up, they are at high-risk for lung infections. In fact, that’s one of the most common causes of death in these patients – so protecting their airway becomes one of our top priorities.

When we consider other things we do to support these patients, we need to always remember their comfort and quality of life. These disease can be very isolating, so it’s important to encourage family presence and activities the patient enjoys. Patients with neuromuscular disorders also find it hard to communicate because they can’t breathe well enough to talk – so we have nifty gadgets and technology we can use to help them communicate – like this letter board you see here. As nurses, we will be monitoring their secretions and providing suctioning and cough assistance. We can do that manually by pushing on their chest when they exhale, or there’s actually a machine that blows positive pressure into their lungs and then literally sucks the secretions out like a vacuum. And then, of course, we need to prevent infection since we know they’re at high risk.

As we’re caring for these patients, our priority needs to be oxygenation and gas exchange – we’re making sure they have a patent airway, that their secretions are managed, and monitoring SpO2 and ABG’s to make sure they’re getting sufficient gas exchange. But, we also want to focus on coping. These diseases can be very stressful for the patient and hard on families. Encourage expression and family time. It will make a world of difference in the patient’s quality of life. Make sure you check out the careplan attached to this lesson to learn more about what we can do for these patients and why we do it..

So just to recap – restrictive lung diseases restrict the expansion and contraction of the lungs and therefore limit total lung capacity and gas exchange. The most common causes are pulmonary fibrosis and neuromuscular diseases. We need to make sure we support their breathing, coughing, and managing their secretions. And we need to remember that these terminal illness can be isolating and hard on families – we want to support their coping process and optimize their quality of life.

We have the ability to truly make a difference with these patients who are struggling. We want each of you to be remembered by your patients not because you knew everything, but for how you made them feel. So go out and be THAT nurse! Happy Nursing!