chest tube

**Indications** - Tension pneumothorax (after emergent needle decompression), large or symptomatic spontaneous pneumothorax, and traumatic pneumothorax (especially if the patient will be ventilated or transported by air) - Hemothorax (the most common indication in trauma), empyema or complicated parapneumonic effusion (pH <7.2, glucose <60, positive Gram stain or culture, or frank pus), and malignant or recurrent effusions - Chylothorax and post-thoracic-surgery drainage

**Placement (ATLS)** - Site: the "safe triangle" in the 4th-5th intercostal space (about the nipple level), anterior to the midaxillary line. It is bordered by the lateral edge of the pectoralis major, the lateral border of the latissimus dorsi, and a line at the level of the nipple (5th ICS). - Technique: Make the incision, then do blunt dissection over the **superior border of the rib**. The intercostal vein, artery, and nerve (VAN) run in the costal groove along the **inferior** border of the rib above, so going over the top of the rib avoids them. Pop through the parietal pleura and do a finger sweep to confirm intrapleural entry and clear adhesions. Direct the tube posteriorly and superiorly for pneumothorax or posteriorly and inferiorly for fluid. Then secure the tube and obtain a CXR. - Layers crossed: skin → subcutaneous tissue → intercostal muscles → parietal pleura → pleural space.

**Drainage system (three-chamber)** 1. Collection chamber: collects fluid and blood and allows output to be measured. 2. Water seal chamber: a one-way valve that lets air out but not back in. **Tidaling** (fluctuation with respiration) shows the tube is patent and in the pleural space. **Continuous bubbling** means an ongoing air leak (e.g., bronchopleural fistula or a loose connection). 3. Suction control chamber: regulates suction, typically -20 cmH2O.

**Management and removal** - Output is monitored. The tube is often removed when the air leak has resolved and the drainage is <200 mL/day (roughly 150-200 mL/24h), with CXR confirmation of lung expansion. - Removal is done at end-expiration or during a Valsalva maneuver to prevent re-entry of air. Place an occlusive dressing.

**Trauma thresholds** - Hemothorax: **>1500 mL** immediately on placement, or **>200 mL/hr for 2-4 hours**, is an indication for emergent thoracotomy.

**Complications** - Malposition (subcutaneous or too deep, e.g., into the fissure) - Injury to the intercostal vessels or nerve, lung, diaphragm, liver, or spleen (if placed too low) - Infection or empyema (give prophylactic antibiotics in trauma per local policy) - Re-expansion pulmonary edema (after rapid drainage of a large, chronic effusion or pneumothorax) - Persistent air leak, subcutaneous emphysema, tube dislodgement, or clogging

**Board pearls** - Hemodynamically unstable patient with absent breath sounds, hyperresonance, tracheal deviation, and distended neck veins has tension pneumothorax. Treat with **immediate needle decompression** (2nd ICS midclavicular line, or 4th-5th ICS anterior axillary line per current ATLS), followed by a chest tube. Don't wait for imaging. - The finding that a chest tube is no longer "tidaling" can mean the lung has re-expanded, but it can also mean the tube is clogged or kinked. - Chest tube output that is chylous (milky, triglycerides >110 mg/dL) suggests thoracic duct injury. - Pleural fluid analysis uses **Light's criteria** to separate exudates from transudates. - Small-bore pigtail catheters are increasingly used for simple pneumothorax and effusion, while large-bore tubes (28-36 Fr) are preferred for hemothorax to prevent clotting.