Overview of Lung Volume Reduction Surgery
Lung volume reduction surgery, or LVRS, is a medical operation that helps patients with severe emphysema. Emphysema is a long-term lung disease usually caused by extended smoking or exposure to harmful elements in the environment. This condition gradually destroys lung tissue, which can make breathing difficult and significantly reduce a person’s quality of life. LVRS involves the removal of the damaged, non-working parts of the lung. This allows the remaining, healthier lung tissue to expand and function more effectively.
LVRS was first introduced in the 1950s, but it only truly gained attention in the 1990s when advancements in surgical technology and the ability to manage potential complications made it a more appealing option. In 2003, the results of a significant, collaborative research effort to study LVRS were published. This study, called the National Emphysema Treatment Trial, helped us understand the impact of LVRS on a patient’s quality of life and survival rate compared to other treatments. These research findings help doctors determine which patients could benefit most from LVRS.
While LVRS can potentially improve a patient’s quality of life, it also involves considerable risks. Therefore, doctors need to carefully assess each patient’s situation and use precise surgical techniques to carry out the procedure. Several important topics of research are linked to LVRS, like its long-term effects on patients, comparing the effectiveness of surgery on one lung versus both lungs, weighing the costs against the benefits, and exploring if LVRS can be used as a steppingstone towards a lung transplant. This piece offers an overview of how LVRS works, including its uses, how we decide who the best candidates are, the details of the surgical procedure, and possible complications, shining a light on LVRS’s role in the overall approach to managing severe emphysema.
Anatomy and Physiology of Lung Volume Reduction Surgery
LVRS, or Lung Volume Reduction Surgery, is mainly used for patients who have severe emphysema. Emphysema is a type of chronic obstructive pulmonary disease (COPD), which affects the lungs, making it hard for people to breathe and limiting their quality of life. With emphysema, the tiny air sacs in the lungs that allow for oxygen exchange, called alveoli, become damaged. This damage creates larger, nonfunctioning air spaces, known as bullae, which trap air and cause the lungs to overinflate, disrupting normal breathing. The overinflated lungs restrict the muscle that helps us breathe, the diaphragm, making it harder for it to function correctly, reducing the effectiveness of the entire respiratory system. There are medical tests that show this obstructive process, which includes an increase in residual capacity, or the amount of air left in the lungs after an exhale, and a decrease in inspiratory capacity, or the maximum volume of air that can be inhaled after a normal exhalation.
Early medical interventions aimed to modify the chest wall or diaphragm. However, modern treatments for emphysema now include transplantation, bullectomy (removal of a bulla), and LVRS. The purpose of bullectomy and LVRS is to reduce the overinflation of the lungs, which in turn improves lung function, capability for exercise, and survival rates. Research has shown that while bullectomy can quickly relieve shortness of breath and improve some lung function tests, the benefits may decrease over time. In contrast, LVRS has been shown to improve respiratory muscle strength for a longer period, improving breathing mechanics for certain patients.
The parts of the lungs most relevant to LVRS are the upper lobes, which tend to be worst affected by emphysema compared to the lower lobes. Usually during surgery, about 20% to 30% of the most damaged lung tissue is removed. This is typically from the upper lobes of the lungs. LVRS works by removing the overinflated, non-working parts of the lungs, which decreases the amount of residual volume. This in turn improves the mechanics of the lungs and the patient’s ability to breathe.
The operation also has several benefits for lung function:
- The removal of overinflated, non-working lung tissue allows the remaining healthier lung tissue to expand well, reducing lung volume and helping the diaphragm function more effectively.
- By reducing the amount of ‘dead space’ in the lungs where no gas exchange can happen, LVRS can improve the efficiency of oxygen exchange. Consequently, it improves oxygen and carbon dioxide removal, reducing breathlessness and increasing capacity for physical activities.
- Serious lung over-inflation can negatively affect the heart by pressing against it and reducing the volume of blood it can pump. By reducing lung volume, LVRS can lessen this compression, potentially improving heart function.
In summary, LVRS targets the most disease-afflicted areas of the lungs, often the upper lobes, to enhance the functioning of the lungs and breathing overall. This surgery helps reduce lung over-inflation, improves the function of the diaphragm, enhances oxygen exchange, reduces the effort of breathing, and may have a positive impact on heart function. Altogether, these improvements can significantly improve the quality of life and exercise capacity for patients with severe emphysema.
Why do People Need Lung Volume Reduction Surgery
The National Emphysema Treatment Trial (NETT) conducted in 2003 was a big step forward for emphysema care. The trial involved 17 institutions and more than 1000 patients. The aim was to compare the effectiveness of just using medicine to treat emphysema with an approach that combined medicine with a surgical procedure called lung volume reduction surgery (LVRS). This study is now the basis for deciding which patients should have LVRS.
Patients are considered suitable for the surgery based on five conditions:
- A body mass index (BMI) under 32 kg/m2
- A Forced-Expiratory Volume in 1 second (FEV1), a measure of lung function, of less than 45% predicted
- A PaCO2, a measure of carbon dioxide in the blood, of less than 60 mm Hg
- A PaO2, a measure of oxygen in the blood, of more than 45 mm Hg
- An ability to walk a distance of more than 140 m in a 6-minute walk test
- Not smoking for at least 4 months before initial screening
The surgery patients in the NETT trial had an average oxygen level (PaO2) of 64 mm Hg and carbon dioxide level (PaCO2) of 43 mm Hg. They found that for patients who are not at high risk, surgery was more beneficial if emphysema was mainly in the upper lobes of their lungs and they had a low baseline exercise capacity. A low exercise capacity was defined as less than 25 workloads (W) for women and less than 40 W for men.
When a Person Should Avoid Lung Volume Reduction Surgery
A significant study called the NETT trial set a guideline to stop the study if more than 8% of patients died within 30 days. This trial was conducted on patients receiving a specific treatment, monitored closely with different patient groups having a procedure known as LVRS. The research found that some patients were at a higher risk of dying post-surgery. These patients had less than 20% of the expected lung function, measured by an FEV1 test, and either less than 20% of expected carbon dioxide removal, measured by a DLCO test, or they had evenly distributed lung damage, called homogenous emphysema.
This high-risk group, FYI, consisted of:
– Those whose lungs could only force out less than 20% of the air (measured by FEV1),
– Those who had less than 20% of normal carbon dioxide removal (measured by DLCO), OR
– Those with evenly spread lung damage (detected by a type of X-ray scan).
It was observed that these high-risk patients were more likely to be harmed by the surgical treatment for the severe lung problem known as emphysema and had a higher chance of dying post-surgery.
On the other hand, patients who weren’t as high-risk were divided into four different groups, based on the severity and pattern of their disease, as well as their physical fitness levels. For the group of these patients with their illness majorly in non-upper parts of their lungs and low physical strength, the surgery didn’t help them live longer. Among those with high fitness levels and similar lung damage, the surgery actually increased the chance of dying and didn’t make their physical strength any better.
Equipment used for Lung Volume Reduction Surgery
The tools needed for Lung Volume Reduction Surgery (LVRS) – a procedure that removes some of the damaged lung tissue, may vary depending on the specific way the doctor chooses to perform the operation. Generally, doctors use one of two methods to conduct LVRS and these methods may vary between different hospitals:
- A method called Median sternotomy, which involves a cut down the middle of the chest.
- A method called Video-assisted Thoracoscopic Surgery (VATS), which uses a small video camera to aid the surgery.
Specialized surgical tools, like a chest bone (sternal) saw for median sternotomy or equipment to inflate the chest cavity and camera for VATS, need to be arranged before the surgery. Anesthesia requirements, such as breathing tubes that go into both lungs (double-lumen endotracheal tube), inserting/monitoring an arterial line (for checking blood pressure directly from an artery), and methods to control pain during and after the surgery using techniques like spinal anesthesia (epidural), nerve block (an injection to numb a specific area of the body), or a patient-controlled pain relief system, should also be decided before the surgery.
Although some hospitals use additional material along with their stapler to try and prevent any leakages of air, until now, there’s no evidence that this reduces the chances of air leakages after surgery in LVRS patients.
Who is needed to perform Lung Volume Reduction Surgery?
A special kind of doctor known as a thoracic surgeon is needed for a surgical operation on the lungs called Lung Volume Reduction Surgery (LVRS). A thoracic surgeon is a doctor who specializes in operations on the chest. Other medical staff, such as a surgical assistant, nurses who work in the operating room, and an anesthesiologist (a doctor who makes you sleep during the operation), work together closely during the surgery.
After the operation, the care continues and it is carried out by medical professionals who are experienced in looking after patients who had chest operations. They take care of things like controlling pain, managing chest tubes (drains used to remove air, fluid, or pus from the chest), and maintaining a strict plan for keeping the bowel healthy and functioning well. This care after an operation is called postoperative care.
Usually, before and after the operation, the patient will be in the care of a pulmonologist. A pulmonologist is a doctor who specializes in lung conditions. Patients with severe lung conditions, like emphysema (a disease where the lungs are damaged and make it hard to breathe), will be regularly monitored by the pulmonologist before and after the operation.
Preparing for Lung Volume Reduction Surgery
Before having a lung volume reduction surgery (LVRS), it’s important for patients with severe chronic obstructive pulmonary disease (COPD) to have several tests done. These tests help doctors decide if the surgery is the best option for them compared to other treatments for COPD. These tests include having images taken of your chest, like an X-ray or a high-resolution CT scan.
Lab tests, like checking the gases in your blood (arterial blood gas), are also done. Pulmonary function tests measure how well your lungs are working and include values for FEV1 (forced expiratory volume in 1 second – measures the air volume you are able to exhale forcefully in one second) and DLCO (diffusing capacity of the lungs for carbon monoxide – shows how well the lungs are exchanging gases).
A common test called the 6-minute walk test is also typically done to see how much oxygen you need and how far you can walk in six minutes. This test also helps to measure any improvements after rehabilitation.
If a heart disease like coronary artery disease is suspected, a heart test (electrocardiogram) and a stress test may be done.
Before surgery, most people join a special lung exercise program (pulmonary rehabilitation) for a few weeks to see if they can improve their ability to exercise. Quitting smoking is also required, typically for over six months. After the LVRS surgery, it’s recommended that patients continue with a pulmonary rehabilitation program to aid in recovery.
How is Lung Volume Reduction Surgery performed
The National Emphysema Treatment Trial (NETT) is a medical study that compared different surgical methods to treat a lung disease called emphysema. These methods included opening the chest through a long cut down the middle (median sternotomy), or a less invasive procedure that uses several smaller cuts (video-assisted thoracoscopic surgery, or VATS). The choice of method didn’t affect the chances of dying within 90 days, or the amount of blood lost in surgery. However, patients typically healed faster and paid lower hospital costs with the VATS method.
Now, let’s look at both procedures in more detail:
Median Sternotomy
In this procedure, the surgeon makes a long cut down the middle of your chest to reach your lungs. After you’ve been put to sleep with general anesthesia, this cut goes from just under your neck to just above your stomach. The surgeon then lifts your breastbone to see and access your lungs. They look for the most damaged parts of your lungs, usually in the upper parts. About 20 to 30 percent of this tissue is then removed using special tools. Once these parts are removed, the lungs are inflated again, and tubes are placed to help keep your lungs inflated and drained after surgery. The breastbone is put back together with wires, and the cut is sewn back together. This approach allows the surgeon to treat both lungs in one surgery.
VATS
This method is less invasive than median sternotomy, meaning it uses smaller cuts. After anesthesia, your body is positioned on your side so the surgeon can easily reach your lungs. They then make three to four small cuts between your ribs on one side of your chest. The surgeon uses a video camera, called a thoracoscope, inserted through one of the cuts to see what they’re doing. The surgeon uses special tools to remove the damaged parts of your lungs, and staples are used to cut and seal the lung tissue. Then a tube will be placed to help keep your lungs inflated and drained after the surgery. This method usually means less pain after surgery, a shorter hospital stay, and quicker recovery.
Alternative Techniques
Because both procedures have their limits, doctors have developed less invasive alternatives. One of these involves using one-way endobronchial valves (EBVs). They first reported using this in 2003, and since then, multiple studies have seen positive results in patients with severe emphysema. This treatment is now recommended for individuals with severe chronic obstructive pulmonary disease (COPD), another type of lung disease.
Possible Complications of Lung Volume Reduction Surgery
In a study called NETT, researchers looked at the risks of death and heart and lung problems after a specific type of lung surgery. They found that about 5.5% of patients experienced serious heart and lung issues. Even more, between 20% to 30% of a specific group of patients faced major lung and heart complications.
Certain factors can increase the risk of dying after the surgery. For instance, people with a certain type of emphysema (a lung condition) were more likely to die after the surgery.
There are several complications that could happen after this surgery:
* Air leaks: This is the most common problem and happens when the lung tissue doesn’t seal properly after being cut during surgery. This can cause the lung to partially collapse (pneumothorax) and might require further surgery to fix. These air leaks can lead to longer hospital stays, more readmissions to the hospital, needing to go to the intensive treatment unit, and a higher risk of developing pneumonia after operation. However, whether one develops an air leak or not doesn’t seem to have anything to do with the specific way the surgery was performed.
* Infections: After surgery, patients may develop infections like pneumonia, infections where the surgery took place, and infections in the space around the lungs (pleural space). These are big risks and can lead to longer hospital stays, strong antibiotics, or more surgery to drain the infection.
* Heart problems: These could include a heart attack, abnormal heart rhythms, or clots in the lung.
* Lung problems: These could include low oxygen levels, needing to be put on a ventilator again, or needing a procedure to help with breathing.
* Bleeding: Bleeding during or after the operation could require blood transfusions or more surgery.
* Collapsed lung: The lung can partially or completely collapse after surgery, leading to lower lung function and a higher risk of infection.
* Pleural Effusion: This is when fluid builds up in the space around the lungs and might need to be drained. It can make it harder for the lung to fully expand.
* Death: While it doesn’t happen often, there is a serious risk of death, especially for those with severe other illnesses or overall poor health.
What Else Should I Know About Lung Volume Reduction Surgery?
Lung Volume Reduction Surgery (LVRS) is a significant treatment option for people with severe emphysema, especially for those with most of the disease in the upper part of their lungs and low physical endurance. Research has shown that these people can have better survival rates with LVRS compared to merely using medication.
However, this procedure hasn’t been widely used in the United States. Even though studies have suggested that LVRS could both extend life and be cost-effective for patients with upper lobe emphysema and low exercise capacity, its use has not increased significantly.
Finding potential LVRS patients would require effective screening methods, such as imaging, and referring to specialized treatment centers. LVRS could also be a supportive therapy for lung transplant patients, both children and adults, before and after they get their transplant.
Postoperative care for end-stage Chronic Obstructive Pulmonary Disease (COPD) patients, who often have complex medical needs, requires a team-based approach to ensure the best possible results.
Research is ongoing to find out the benefits of less invasive alternative methods to LVRS, like using Endobronchial Valves (EBVs). Various studies, including a large trial known as TRANSFORM, have shown that patients treated with EBVs have significant improvements in their lung function six months after treatment. Borrowing techniques from these less invasive alternatives could optimize LVRS. However, different study designs can sometimes make it difficult to compare results directly.
