A chest tube is a flexible plastic tube inserted through the chest wall into the space between your lungs and ribcage. Its job is to drain air, blood, or fluid that has collected where it shouldn’t be, allowing a collapsed or compressed lung to re-expand. Chest tubes are one of the most common procedures in emergency and surgical medicine, and understanding what they do can make the experience far less intimidating if you or someone you know needs one.
Why a Chest Tube Is Needed
The space surrounding your lungs, called the pleural space, normally contains only a thin layer of fluid that helps your lungs glide smoothly as you breathe. When air, blood, or excess fluid enters that space, it puts pressure on the lung and can partially or fully collapse it. A chest tube restores the normal pressure balance so the lung can inflate again.
The most common reasons for chest tube placement include:
- Pneumothorax: Air leaking from the lung into the chest cavity, whether from trauma, a spontaneous rupture, or mechanical ventilation.
- Hemothorax: Blood collecting in the chest, typically after an injury or surgery.
- Pleural effusion: Excess fluid buildup caused by infection, cancer, or heart failure.
- Empyema: Pus from a lung abscess or severe infection that needs to be drained.
After chest or heart surgery, a tube is often placed preventively to catch any blood or air that accumulates during recovery.
Large-Bore Tubes vs. Pigtail Catheters
Not all chest tubes look the same. Traditional large-bore tubes are 28 to 40 French in diameter (roughly the width of a finger) and are placed through a small incision. These have long been the standard for draining blood or large volumes of fluid after trauma. Pigtail catheters are much smaller, around 14 French, and are threaded in through a needle puncture using a guidewire technique, similar to placing an IV line.
A randomized clinical trial comparing the two in trauma patients found no difference in their ability to drain blood from the chest. Pigtail catheters did, however, result in significantly less pain during insertion. Patients with the smaller catheter described the experience as tolerable, while those receiving the larger tube were more likely to call it a bad experience. Because of less tissue disruption during placement, many centers now prefer pigtail catheters for non-emergency situations.
What Happens During Placement
Chest tubes are typically placed at the bedside rather than in an operating room. You’ll receive moderate sedation along with a local anesthetic injected at the insertion site to numb the area. A longer-acting anesthetic is often added after the tube is in place for extended pain relief.
The tube goes in between the ribs, usually at the fourth or fifth intercostal space along the side of your chest. The exact angle depends on what’s being drained. For fluid, the tube is directed toward the back of the chest cavity, where liquid pools when you’re lying down. For a pneumothorax, the tube is aimed toward the front, where trapped air rises. The needle and tube enter along the top edge of a rib to avoid the nerves and blood vessels that run along the underside of each rib.
Once the tube is positioned, it’s secured to the skin with sutures and connected to a drainage system.
How the Drainage System Works
The tube connects to a bedside unit with three interconnected chambers. The first is a collection chamber where fluid and air drain out of your chest. The second is a water-seal chamber, which holds a small column of water (about 2 centimeters) that acts as a one-way valve. This prevents air from being sucked back into your chest when you breathe in.
The third chamber controls suction. It can use either a water column or a mechanical valve to regulate how much negative pressure pulls air or fluid out of the pleural space. The typical starting suction level is equivalent to negative 20 centimeters of water pressure. In some cases, the system runs on gravity alone with no active suction, which is called being on “water seal.”
Healthcare staff monitor the system by watching for bubbling in the water-seal chamber. Bubbling during exhalation suggests air is still leaking from the lung. When the bubbling stops, it’s a sign the air leak has resolved.
What It Feels Like to Have One
Chest tubes are uncomfortable. The tube passes between ribs, which are surrounded by sensitive nerves, and every breath moves the chest wall around the insertion site. Pain management is a priority throughout treatment. Early movement and deep breathing exercises are encouraged despite the discomfort because they help prevent parts of the lung from staying collapsed.
Intercostal nerve injury during placement can occasionally lead to lingering pain at the insertion site even after the tube is removed. This is more common with larger tubes that require a surgical incision for placement.
Possible Complications
A systematic review and meta-analysis found an overall complication rate of about 19% across all chest tube placements. That number sounds high, but more than half of those complications were positional, meaning the tube shifted or wasn’t in the ideal spot after placement, rather than causing direct injury. Insertion-related injuries to surrounding structures accounted for about 15% of complications, and infection-related issues made up roughly 15% as well.
The good news is that infection rates have dropped dramatically, falling from around 10% in studies before 2000 to about 1% in more recent data, likely due to improved sterile technique and antibiotic use. Serious but rare complications include injury to the lung tissue, major blood vessels, or abdominal organs if the tube is placed too low.
When the Tube Comes Out
A chest tube stays in place until the problem it was placed to treat has resolved. For a pneumothorax, that means no air leak for at least 24 hours, confirmed by the absence of bubbling in the water-seal chamber and a chest X-ray showing the lung has fully re-expanded. For fluid drainage, the tube is typically removed when output drops below 100 to 200 milliliters over 24 hours and the fluid isn’t infected or bloody.
Some newer post-surgical recovery protocols allow removal at higher drainage volumes, up to 500 milliliters per day, as long as there’s no air leak, infection, or active bleeding. On the other end of the spectrum, if drainage suddenly exceeds 200 milliliters per hour or initial output after trauma tops 1,500 milliliters, that can signal a vascular injury requiring surgery.
Removal itself is quick. The sutures are cut, you’re asked to take a breath and hold it or breathe out fully (to prevent air from re-entering), and the tube is pulled. A bandage covers the site. Most people feel immediate relief from the pressure and discomfort the tube caused, though soreness at the insertion site can persist for days to weeks.