Overview of Thoracentesis
Thoracentesis is a medical procedure that doctors often use to remove excess fluid from a part of the body called the pleural space. This is usually done so the doctor can find out why the fluid built up in the first place, and also to relieve certain symptoms like shortness of breath. The buildup of fluid might be due to different health conditions such as cancer, infections like pneumonia and tuberculosis, heart failure, and some other systemic diseases.
This procedure is relatively safe and doesn’t pose much risk, although it still needs to be done with care. The information it provides can be extremely helpful in deciding the best way to treat these various health conditions. Doctors need to know the proper way to carry out a thoracentesis, when they should or shouldn’t do it, how to perform it, and what possible complications to watch out for, to effectively manage cases with fluid build-up in the pleural space.
Anatomy and Physiology of Thoracentesis
Thoracentesis focuses on the pleural cavity, which is a space surrounding the lungs, tucked between two layers called pleurae. Picture the pleurae as a thin, folded blanket, with one layer, the visceral pleura, sticking to the lungs, and the second layer, the parietal pleura, attached to the chest wall. This space usually contains a small amount of fluid that helps the lungs glide smoothly as they expand and contract during breathing. The role of the pleural cavity is crucial for normal lung function, as it allows the movements of the chest wall to be passed on to the lungs when we take a deep breath. The two pleural cavities, one for each lung, are distinct and receive blood supply from different vessels.
When there is too much fluid build-up in this space due to an illness, it can result in a condition called pleural effusion. Thoracentesis, a procedure done to remove this excess fluid, can help reduce symptoms like difficulty breathing and assist doctors in diagnosing the underlying disease. This could be heart failure or an infection, as indicated by the amount, speed of accumulation, and type of cells and chemical makeup of the fluid collected. The procedure is usually done between the sixth and eighth ribs counted from the top, depending on whether the patients are lying down or seated. The exact positioning of the patient is important for both accessing the area and keeping the patient as comfortable as possible during this process.
Why do People Need Thoracentesis
Thoracentesis is a procedure that can help both diagnose and treat fluid buildup in the area between the lungs and the chest wall, a space called the pleural space. This procedure involves using a thin needle or tube to remove the fluid, which can relieve symptoms and can also be used to analyze the fluid to figure out what’s causing it to build up.
This procedure can be performed when scans show that there’s fluid in the pleural space. The analysis of this fluid can guide the next steps for treatment.
What are some reasons one might need a thoracentesis for diagnosis? It can help show whether the fluid is a transudate or an exudate. Transudates are usually clear and watery, often caused by pressure changes in your body like in heart failure. Exudates are typically thick and can point to inflammation or infection. The fluid is typically tested for bacteria, cell count, protein levels, enzyme activity (l-lactate dehydrogenase), and acidity (pH). Other tests like screening for tuberculosis might be performed depending on the patient’s risk factors and where they live. Generally, a small amount of fluid (20-30 mL) is removed for diagnostic purposes.
Thoracentesis can be used to figure out why there’s fluid in the pleural space, to see if there’s an infection such as tuberculosis or empyema (pus in the pleural space), or to check whether there’s a malignancy (cancer). It can also differentiate between fluid caused by heart failure and fluid caused by other conditions, such as a blood clot in the lungs (pulmonary embolism) or liver disease (cirrhosis).
Therapeutic thoracentesis is performed if the buildup of fluid is causing significant symptoms. This typically involves removing a larger amount of fluid. The fluid can be tested if the cause of the fluid accumulation is unknown or may have changed. Thoracentesis can make it easier for the lungs to expand, improving symptoms for patients with large pleural effusions. The procedure can be performed to prepare for pleurodesis, a procedure that prevents fluid from building up again, in cases of recurrent fluid accumulation like malignant effusions. Thoracentesis can also be performed to drain infected fluid or blood (hemothorax), and to improve symptoms and speed up recovery. If the fluid is anticipated to build up again quickly, a drain may be left in place for more fluid removal.
Thoracentesis can diagnose and treat parapneumonic effusion, which is excess fluid in the pleural space during a lung infection. This can happen in about 40% of patients hospitalized with bacterial pneumonia and 20% with viral or Mycoplasma pneumonia. If a parapneumonic effusion isn’t treated or the infection is too strong for the immune response, thoracentesis can also be used to treat this frequently seen condition’s more complex stages, when drain placement and possibly antibiotics are needed for resolution.
Apart from pneumonia, thoracentesis can also diagnose and manage other conditions associated with pleural effusions. These can include heart failure, malignancy, a clot in the lungs (pulmonary embolism), liver disease (cirrhosis), and a kidney condition called nephrotic syndrome.
When a Person Should Avoid Thoracentesis
There are a few important reasons why a person may not be able to undergo a procedure called thoracentesis. This is a procedure where fluid is removed from the space between the lungs and chest wall. These reasons include:
1. If a person suffers from bleeding disorders that are not corrected or managed, such as a significant issue with blood clotting (referred to as coagulopathy) or a low platelet count (known as thrombocytopenia). Platelets are a type of blood cell that helps the blood clot and stop bleeding.
2. Having an active skin infection or condition called cellulitis over the area where the needle would go in. This could risk transferring the infection into the space between the lungs and the chest wall.
3. If a person is on a ventilator to help them breathe, this increases the risk of getting a collapsed lung (known as pneumothorax) or damage to the lung due to high pressure (a condition called barotrauma).
4. Patients who are very unstable, in terms of their heart and circulation (a condition known as severe hemodynamic instability). In these cases, thoracentesis may make their condition worse.
5. If the patient has had infections or surgeries before that have caused scar-like tissues (known as pleural adhesions) to form in the space between their lungs and chest wall, it can make it difficult to successfully remove fluid.
Most of these issues can be managed with careful planning and evaluation before the procedure. However, it’s important to thoroughly assess these conditions before moving forward with the procedure.
Equipment used for Thoracentesis
There are ready-to-use kits available commercially for the procedure called thoracentesis. These are convenient, though not a must-have, for performing this procedure safely. Thoracentesis is a medical procedure to remove fluid from the space between the lungs and the chest wall, which your doctor might suggest if there’s too much fluid in there. Here’s the equipment typically used:
- Clean gloves and gown: These are for the doctor to wear during the procedure to maintain cleanliness.
- Antiseptic solution such as chlorhexidine or povidone-iodine: These are used to clean the skin to prevent infection.
- Sterile drapes: These help to keep everything clean during the procedure.
- Local anesthetic: This is a medicine that will numb your skin so you don’t feel pain.
- Syringes and needles: These are needed to give the anesthetic and to withdraw the fluid.
- Thoracentesis needle or catheter; usually a 20- or 22-gauge needle or catheter with a safety valve: This needle is specifically designed for this procedure to take out the fluid safely.
- Three-way stopcock: This tool allows the doctor to control the flow of the fluid.
- Collection bottles or vacuum-sealed containers: These are for collection and holding the fluid that comes out.
- Sterile gauze and bandages: These are used to clean up and cover the puncture site after the procedure.
- Adhesive tape: This is used to secure the bandages in place.
- Ultrasound machine (optional): This machine can help the doctor see exactly where to insert the needle.
- Chest tube set: This might be needed if lots of fluid needs to be drained, or if the chest needs to be drained.
Preparing for Thoracentesis
Before a medical procedure called thoracentesis, doctors must thoroughly assess a patient’s health. This involves gathering a complete medical history, doing a full-body examination, and inspecting medical imaging. The main purpose is to check for and understand any fluid that may be present inside the chest, like a fluid buildup around the lungs known as pleural effusion, or blood in the chest, known as hemothorax.
Patients with these conditions might report breathlessness, difficulty in breathing when lying flat (orthopnea), chest discomfort, sharp chest pain triggered by breathing (pleuritic pain), or a feeling of tiredness. These symptoms suggest that their lungs may not be working as efficiently as they should because of possible irritation or involvement in gas exchange.
During the physical checkup, doctors may discover that the sounds of the patient’s breathing are quiet or even silent. When doctors tap on the patient’s chest, it may sound dull, which can also suggest fluid buildup. If the fluid amount is big, it might force the heart and airways to shift to one side, which is a situation that can be identified during the examination.
Medical imaging is an indispensable part of preparation for thoracentesis. Chest X-rays are often done to visualize the amount and position of the fluid. Portable ultrasound scans have become a fundamental tool in the early diagnosis, detecting small fluid buildups and complications such as infection or cancer in the pleura, which is the area surrounding the lungs. Ultrasound is also used for real-time guidance during the thoracentesis procedure to lower the chance of complications. The efficiency of the ultrasound can be impacted by how the ultrasound wave interacts with the body tissues and the air, leading to various imaging effects like A-lines, “comet tail,” and B-lines. The presence of B-lines in the ultrasound image is highly specific for fluid within the lung tissues and air spaces. These findings can quickly refine the possible causes and steer the initial treatment approach when evaluating a patient with breathlessness.
A CT scan of the chest can also help rule out other reasons for shortness of breath and may point to a complex fluid accumulation due to lung infection or cancer.
Once the doctor decides that thoracentesis is necessary, they will explain the procedure to the patient and get their permission to proceed. The doctor will clearly mark the correct side and spot for the puncture according to the hospital’s guidelines. All the necessary tools for the procedure are gathered before it begins. Throughout the process, the patient’s vital signs, including blood oxygen levels, blood pressure, and heartbeat, are closely watched to ensure safety.
How is Thoracentesis performed
Thoracentesis is a procedure to remove fluid from the space between the lungs and the chest wall. This can be done while you’re sitting up or lying down, depending on what’s more comfortable or necessary for your situation. The doctor does the procedure on the side where the extra fluid is found. With the help of a bedside ultrasound, the doctor can accurately find the best place to insert the needle, especially if the fluid amount is small. The ultrasound creates pictures on a monitor of what’s happening inside your body and helps the doctor avoid harming any surrounding structures.
The area for the procedure gets cleaned with an antiseptic solution and covered with drapes to keep it sterile. To help with any discomfort, the doctor will give you local anesthesia using a small needle to numb surface skin and then a slightly bigger needle to numb deeper tissues. After this, a bigger needle or a tube connected to a syringe will be inserted into your skin and directed towards the fluid. The doctor will slowly pull back the syringe’s plunger (applying negative pressure) while inserting the needle to draw up the fluid and avoid injury to other areas. In some cases, the doctor might make a small cut in your skin to help the insertion of a tube if that is used. As soon as the fluid starts to enter the syringe, the tube or needle is pushed deeper into your chest cavity, and the necessary amount of fluid is removed.
If your doctor is just trying to identify what’s causing the extra fluid, they might only take a small sample. But if the purpose is to remove a larger quantity of fluid for relief, this can be done slowly by letting gravity do the work or have the doctor manually draw it out with the syringe. The removed fluid may be collected in a bag.
Once enough fluid is drained, the needle or tube is removed, and pressure is applied to the skin to prevent bleeding. If the fluid is expected to build up again due to conditions like injuries, cancer or after surgery, a drain might be left in the chest. Also, the collected fluid is usually tested, especially if the cause of fluid build-up is unknown or thought to have changed.
Possible Complications of Thoracentesis
After a thoracentesis, which is a procedure to drain fluid from the space between the lungs and the chest wall, some people might experience complications such as bleeding, pain, and infection at the spot where the needle was inserted. Sometimes, if the needle is placed too high, it could damage blood vessels and nerves. If too much fluid is removed, or if the fluid is removed too quickly, it could cause lung problems and fainting. If the needle is passed through infected or diseased tissue before it’s inserted into the chest cavity, it could spread the infection or disease to the chest space. If the needle is inserted too low, it could potentially puncture the spleen or liver.
The most common problem after this procedure is pneumothorax, a condition where the lung collapses due to air that fills up the chest cavity. This occurs in 12% to 30% of procedures. To check for this, doctors usually take chest X-rays before and after the operation. Rarely, part of the catheter – the tube used to drain fluid – could be left behind in the chest cavity. This tends to happen when the catheter is manipulated while still inside the body.
Before starting the procedure, doctors check for ‘lung sliding’ which indicates the lung is working properly. If lung sliding or certain ultrasound signs like ‘B-lines’ disappear, it could mean a pneumothorax has occurred. In such instances, a chest tube might be inserted to manage the pneumothorax. This is especially likely in patients on mechanical ventilators.
What Else Should I Know About Thoracentesis?
Thoracentesis is an important medical procedure that can be used for both diagnosing and treating certain health conditions. It involves using a needle to remove excess fluid from the space between the lungs and the chest wall, also known as the pleural space. This procedure is often used when conditions such as heart failure, infections, cancers, and swelling-related diseases cause fluid to build up in this space.
Removing this excess fluid can help relieve symptoms like shortness of breath and chest pain, making it easier for the patient to breathe and improving their overall comfort. The procedure is very important in assessing and managing the fluid build-up, known as pleural effusions.
From a diagnosis standpoint, thoracentesis is very useful. It allows doctors to examine the removed fluid through various lab tests. These tests can help doctors understand if the fluid build-up is due to a condition like an infection, cancer, or an immune system disorder. This knowledge helps doctors decide on the best treatment plan and determine if more tests are needed.
Aside from diagnosis, thoracentesis is also a valuable treatment. It provides immediate relief from symptoms caused by a large amount of fluid in the pleural space, which lowers the risk of complications like trouble breathing or infection. This procedure is also helpful in managing and monitoring conditions such as lung-related infections (parapneumonic effusion) or pus in the pleural space (empyema), by helping to drain the fluid and preventing the condition from further worsening.
In conclusion, thoracentesis is an essential procedure in both urgent and prolonged care settings. It serves a critical role in diagnosing and treating a variety of lung-related conditions, which ultimately helps manage patient care and improve health outcomes.
