A chest tube, technically known as a thoracostomy tube, is a flexible, hollow catheter inserted through the chest wall into the pleural space (the space between the lung and the inner chest wall). Its primary function is to drain unwanted accumulations of air, fluid, or blood that have built up in this space. This procedure restores normal pressure within the chest cavity, allowing a collapsed or compressed lung to re-expand and function properly.
The insertion of a chest tube is a serious procedure performed only by highly trained medical professionals in a controlled setting, such as a hospital or an emergency department. By removing the material causing compression, the chest tube facilitates lung expansion and relieves the patient’s difficulty breathing.
Medical Conditions Requiring Chest Tube Insertion
The presence of air or fluid in the pleural space creates specific pathologies requiring drainage. The most common condition is a pneumothorax, or collapsed lung, which occurs when air leaks into the pleural space, exerting pressure on the lung tissue and preventing full expansion. This can result from trauma, lung disease, or certain medical procedures; a tension pneumothorax where air cannot escape is a life-threatening emergency.
Another condition is a hemothorax, which involves the accumulation of blood in the pleural space, typically following severe chest trauma or major surgery. Any significant fluid buildup around the lungs is broadly termed a pleural effusion, which can also be caused by heart failure, infection, or cancer. When this fluid is thick pus due to infection, the condition is called empyema, which also requires drainage.
Patient Positioning and Pre-Procedure Setup
Preparing the patient and the insertion site begins well before the first incision. The patient is typically positioned semi-recumbent or supine, with the arm on the affected side raised above the head to expose the axillary region. This positioning maximizes the space between the ribs and exposes the optimal insertion zone.
The procedural site is selected using specific anatomical landmarks, most commonly within the “triangle of safety,” located on the lateral chest wall. This triangle is bordered by the lateral edge of the pectoralis major muscle anteriorly, the anterior edge of the latissimus dorsi muscle posteriorly, and a horizontal line from the nipple inferiorly, usually correlating with the fifth intercostal space. This area is chosen because it minimizes the risk of injury to underlying organs and major neurovascular structures.
Once the area is identified, the skin is thoroughly cleaned with an antiseptic solution, such as chlorhexidine, and sterile drapes are applied to create a sterile field. Local anesthetic, typically lidocaine, is then infiltrated through the skin, muscle, and down to the parietal pleura. Sufficient time is allowed for the medication to numb the tissues, which is important as the pleura is highly sensitive.
Step-by-Step Guide to Insertion
The insertion process begins with a small transverse or horizontal incision, generally two to three centimeters in length, made through the skin over the rib below the chosen intercostal space. The surgeon then uses a large, curved instrument, such as a Kelly clamp, to begin a blunt dissection through the subcutaneous tissue and muscle layers. This technique is preferred over a sharp dissection because it allows the operator to feel the tissue layers and gently separate them, reducing the risk of accidental organ injury.
The clamp is advanced just above the superior border of the lower rib within the intercostal space. This placement avoids the intercostal neurovascular bundle that runs along the underside of the rib above. Once the clamp reaches the parietal pleura, it is pushed through with steady pressure to enter the pleural space, then opened and withdrawn to widen the tract, creating a tunnel for the tube.
The operator then inserts a finger into the opening, known as a “finger sweep,” to confirm entry into the chest cavity and check for any lung adhesions. Finally, the chest tube, held by the clamp or guided by the finger, is advanced through the tunnel and into the pleural space. The tube is directed superiorly and anteriorly for a pneumothorax or posteriorly and inferiorly for fluid drainage.
Correct placement is confirmed when the drainage holes on the tube are well inside the chest cavity. The tube is then secured to the skin with a heavy suture, often using a horizontal mattress stitch, to prevent it from slipping out or migrating.
Post-Insertion Management and Tube Removal
After the chest tube is secured, its end is connected to a closed drainage system that maintains a water seal, acting as a one-way valve to prevent air from re-entering the chest. This system typically includes a collection chamber, a water seal chamber, and a suction control chamber to regulate negative pressure applied for drainage. The amount of fluid drained and the presence of any air leaks, indicated by bubbling in the water seal chamber, are continuously monitored.
Criteria for removing the chest tube are based on the resolution of the underlying condition and the stability of the patient. The tube is ready for removal when fluid drainage is minimal (often less than 150 milliliters over 24 hours) and there is no evidence of an air leak. A chest X-ray is performed to confirm that the lung is fully re-expanded and that there is no residual air or fluid.
The removal procedure requires careful coordination to prevent air from re-entering the pleural space. The patient is instructed to perform a Valsalva maneuver (taking a deep breath and holding it) just as the physician quickly pulls the tube out. Immediately after removal, an occlusive dressing, typically coated with petroleum jelly, is placed over the site and secured to create an airtight seal. The patient is monitored closely for any signs of respiratory distress, and a follow-up chest X-ray is often taken a few hours later to ensure the lung remains fully expanded.