Chest tube nursing: a guide for nursing students

Chest tube therapy is one of the highest-stakes nursing responsibilities in acute and critical care. The device is simple — a flexible tube placed through the thoracic wall into the pleural space — but the nursing demands are not. Every nurse caring for a patient with a chest tube must understand why it is there, how the drainage system works, what normal looks like, and what signs demand an immediate response. NCLEX tests chest tubes extensively, and clinical practice offers almost no margin for error.

This guide covers indications, three-chamber mechanics, drainage assessment, nursing priorities, troubleshooting, and removal — with a focused set of high-yield NCLEX discriminators at the end.

Indications

A chest tube (also called a thoracostomy tube or tube thoracostomy) is inserted to drain air, fluid, or both from the pleural space. The normal pleural space contains only a few milliliters of lubricating fluid; any abnormal accumulation impairs lung expansion and can compromise hemodynamics.

Tube size matters. Smaller tubes (14–22 Fr) are adequate for air drainage. Larger tubes (28–32 Fr) are used when blood or thick fluid must drain freely. Post-cardiac surgery patients often have two mediastinal tubes.

Water-seal chamber mechanics

The water-seal drainage system is the most heavily tested aspect of chest tube nursing. Understanding the physics prevents errors and makes NCLEX questions straightforward.

The three-chamber system

Modern chest drainage systems (Pleur-evac and equivalents) consolidate three functional chambers into a single disposable unit. Understanding each chamber individually is essential.

Chamber 1 — collection chamber. This is the right-most chamber where drainage actually collects. It is graduated in milliliters so you can measure output precisely. Fluid drains here by gravity from the pleural space and stays separate from the other two chambers. You document the drainage level at regular intervals and mark it with a pen or tape.

Chamber 2 — water-seal chamber. This is the heart of the system. It contains approximately 2 cm of sterile water that acts as a one-way valve: air and fluid can leave the pleural space (bubbling up through the water and escaping), but outside air cannot travel backward into the chest. This directional seal is what prevents atmospheric pressure from collapsing the lung.

The water-seal chamber produces two observable phenomena that every nurse must interpret correctly:

• Tidaling (fluctuation): The water level in the water-seal chamber rises on inspiration and falls on expiration in a spontaneously breathing patient — the reverse in a mechanically ventilated patient. This fluctuation reflects changes in intrapleural pressure with each breath. Tidaling tells you the tube is patent and connected to the pleural space. It is normal and expected.

• Bubbling: Intermittent gentle bubbling during normal breathing is expected when there is an air leak from the lung (e.g., pneumothorax draining). As the lung heals, bubbling diminishes and stops. Continuous, vigorous, unremitting bubbling throughout the respiratory cycle is abnormal — it indicates an air leak somewhere in the system, either at the tube insertion site, at a connection point, or within the lung itself. Trace the system from patient to collection unit to find the source.

Chamber 3 — suction control chamber. This chamber limits suction to a safe level regardless of how much suction the wall unit applies. It contains water (typically enough to produce −20 cmH₂O of suction) and a vent to atmosphere. When wall suction is active, you should see gentle, continuous, quiet bubbling in this chamber — that is correct function. Vigorous, noisy bubbling in the suction control chamber does not produce more suction; it wastes energy and causes unnecessary turbulence. Reduce wall suction until bubbling is gentle.

Standard ordered suction is −20 cmH₂O. Some orders specify −10 to −15 cmH₂O for smaller pneumothoraces. If suction is not ordered, gravity drainage alone (“water seal only” mode) is appropriate — simply disconnect from wall suction but leave the suction port open to atmosphere via its vent.

Clamping: when and never

Clamping stops airflow and drainage through the tube. This is occasionally necessary — and occasionally catastrophic.

You DO clamp when:

• Changing a broken or contaminated drainage system (clamp briefly, swap, unclamp immediately)
• Testing for an air leak (clamp momentarily to see whether bubbling in water-seal stops — if it does, the leak is at or below the clamp; if bubbling continues, the leak is between the clamp and the patient)
• Ordered by provider for a specific diagnostic reason

You NEVER clamp for:

• Tension pneumothorax — clamping with active air accumulation traps pressure in the chest and is fatal
• Ambulation or transport without explicit provider order to clamp
• Routine position changes

The rule: When in doubt, do not clamp. An open tube that drains freely cannot cause tension pneumothorax. A clamped tube with ongoing air leak can kill the patient within minutes.

Drainage assessment

Systematic, documented assessment of chest tube output is a core nursing responsibility — performed at least every shift, and more frequently in the immediate post-operative or post-insertion period.

Drainage characteristics

Volume thresholds

Normal post-operative drainage is typically 100–200 mL in the first few hours, tapering to less than 200 mL over the subsequent 24 hours. The key threshold to know for NCLEX and clinical practice:

Greater than 200 mL per hour of bright red drainage = active hemorrhage. Notify the provider immediately. This is the threshold that triggers urgent evaluation — potential return to the OR, massive transfusion activation, or autotransfusion (collecting shed blood and re-infusing it via autotransfusion system).

Clot formation and tube patency

Blood in the collection chamber can clot and obstruct drainage. Stripping or milking the chest tube — squeezing the tubing to manually advance clots — was historically common but is now discouraged. The negative pressure generated can damage pleural tissue and does not reliably improve drainage. Some cardiac surgery protocols still permit “gentle milking” of mediastinal tubes; follow the specific facility protocol.

Monitor for clot formation by tracking output trends: a sudden stop in drainage from a previously draining tube warrants assessment for tube kinking, clot, or lung re-expansion.

Nursing priorities

Positioning

The patient should be in semi-Fowler’s position (30–45 degrees) unless contraindicated. This position promotes lung expansion and allows fluid to drain by gravity. Patients can be repositioned and ambulated with a chest tube in place, provided the drainage system stays below chest level and remains upright throughout.

Tubing management

Poor tubing management is the most common preventable complication at the bedside. Follow these principles without exception:

• No dependent loops. Loops in the tubing create a fluid trap that generates back-pressure and impairs drainage. Keep tubing in a straight or gently coiled path from the patient to the collection unit.
• No kinking. Kinked tubing stops drainage and can cause pressure buildup. Secure tubing loosely to the bed linen, not the side rail — the rail moves independently and will kink the line.
• No tension on the insertion site. A pull on the tube can dislodge it or cause pain. Secure at least 6 inches from the chest wall with a loop of slack before anchoring.
• The drainage system must always sit below the level of the chest. If the collection unit rises above the insertion site, drainage reverses back into the pleural space. This applies at all times: at rest, during transport, during transfers.

Insertion site and dressing

An occlusive dressing covers the insertion site at all times. For a closed tube thoracostomy (standard clinical placement), a four-sided occlusive dressing is used — sealed on all four edges. For an open pneumothorax (sucking chest wound from penetrating trauma), a three-sided occlusive dressing is applied: three edges sealed, one edge open. The open edge acts as a flutter valve — sealed on inspiration to prevent air entry, open on expiration to allow air escape.

Inspect the insertion site with each dressing change or at minimum every shift:

• Assess for subcutaneous emphysema (crepitus on palpation — tissue feels like bubble wrap)
• Inspect for signs of infection (erythema, warmth, purulent drainage, fever)
• Confirm sutures are intact
• Note any tube migration (mark the tube at skin level during initial placement)

Monitoring for complications

Tension pneumothorax is the most immediately life-threatening complication associated with chest tube management. It occurs when air accumulates in the pleural space faster than it escapes — often when a tube becomes obstructed or clamped inappropriately.

Classic triad: tracheal deviation away from the affected side + absent breath sounds on the affected side + hypotension (obstructive shock from mediastinal shift compressing the heart and great vessels). Distended neck veins (JVD) are also present when the patient is not also hypovolemic.

Response: Do NOT clamp the tube. Release any occlusive seal or clamp. Notify the provider immediately. Prepare for needle decompression (second intercostal space, midclavicular line, affected side) or immediate chest tube reposition. This is a minutes-to-death emergency.

For patients on mechanical ventilation, peak airway pressure rises and oxygenation deteriorates — monitor both vigilantly in mechanically ventilated patients with chest tubes.

Troubleshooting

System dropped or broken

If the collection unit is dropped and the water seal is disrupted, submerge the distal end of the chest tube in 2 cm of sterile water immediately to re-establish the seal while a replacement unit is obtained. A cup of sterile water or saline at the bedside is standard in many ICUs for this reason. Never leave the tube open to air for more than a few seconds.

Continuous bubbling throughout the respiratory cycle

This indicates an air leak. Systematically trace from patient to system:

1. Inspect the dressing and insertion site — is air escaping at the skin?
2. Check all connections along the tubing — are they tight and taped?
3. Check the collection unit for cracks
4. If all connections are intact and the leak persists, the source is within the lung itself (bronchopleural fistula or persistent parenchymal leak) — document and notify the provider

No tidaling

Absence of the expected rise-and-fall in the water-seal chamber has two possible causes — one reassuring, one requiring intervention:

• Lung re-expanded: The most desirable explanation. Confirm with chest X-ray. If the lung is fully re-expanded, the tube may be ready for removal.
• Tube kinked, clamped, or clogged: The tube has lost patency. Inspect the tubing for kinks, loops, or clots. A tube with no tidaling AND continued respiratory distress is kinked or blocked until proven otherwise.

Subcutaneous emphysema

Air tracked into the subcutaneous tissues presents as crepitus — a crackling sensation on palpation around the insertion site and potentially spreading toward the face, neck, or chest wall. Mild subcutaneous emphysema is common after chest tube insertion and is usually self-limiting. Rapid spread, however, indicates ongoing air leak or inadequate drainage — notify the provider and increase suction as ordered.

Patients with pneumothorax already present with subcutaneous emphysema in some cases, particularly after traumatic injury.

Hemothorax and hemorrhagic shock risk

Large-volume hemothorax can precipitate hemorrhagic shock. Any patient draining bright red blood at a significant rate warrants a concurrent IV access assessment (large-bore IV secured), blood type and crossmatch confirmation, and heightened hemodynamic monitoring. For management of thoracic and pleural fluid conditions, including malignant effusion and parapneumonic processes, see the pleural effusion nursing guide.

Chest tube removal

Criteria for removal

Removal requires all of the following:

• Lung re-expansion confirmed on chest X-ray (CXR)
• Drainage has decreased to less than 50–100 mL per 24 hours (varies by provider and facility)
• No air leak for at least 24 hours (water-seal chamber shows no bubbling)
• Suction has been successfully weaned to water-seal-only without recurrence of pneumothorax

Some providers trial water seal for 4–6 hours before pulling the tube and obtain a CXR to confirm stability.

Removal technique

Chest tube removal requires two people — one to remove the tube, one to manage the dressing. The procedure is performed on controlled exhalation or Valsalva maneuver (patient takes a deep breath and bears down), which raises intrapleural pressure, minimizes air entry at the moment of removal, and allows the site to seal quickly.

Steps:

1. Gather supplies: suture removal kit, occlusive petroleum (Vaseline) gauze, additional gauze, tape
2. Pre-medicate for pain — removal is uncomfortable
3. Remove the anchoring suture (if separate from the purse-string); leave the purse-string in place if present to cinch the site closed on removal
4. Instruct the patient to exhale fully (or perform Valsalva)
5. Remove the tube in one smooth, continuous motion
6. Immediately apply the petroleum gauze (Vaseline gauze) followed by dry gauze — press firmly to create a seal
7. Tape on all four sides (occlusive)
8. Obtain a post-removal CXR within 1–4 hours per provider order

Post-removal monitoring: Assess for recurrent pneumothorax — sudden dyspnea, decreased breath sounds, subcutaneous emphysema. A post-removal CXR typically confirms re-expansion is maintained. Oxygen therapy may be continued to promote nitrogen reabsorption and accelerate resolution of any residual small pneumothorax.

Assess the site with each dressing change for air escape (palpate for crepitus), wound healing, and signs of infection. The site typically heals within days to weeks depending on the tube size.

NCLEX tips

These are the highest-yield discriminators for chest tube questions:

1. Tidaling (fluctuation in the water-seal chamber) is normal — it means the tube is patent and connected to the pleural space. Tidaling stops when the lung re-expands (good) or when the tube is kinked/clogged (bad). Know the difference: a re-expanded lung on CXR = good; respiratory distress + no tidaling = kinked tube.

2. Continuous bubbling in the water-seal chamber = air leak. Bubbling that occurs only with inspiration or coughing may be expected during early pneumothorax drainage. Bubbling that never stops across the entire respiratory cycle is an air leak — trace the system.

3. Gentle, quiet, continuous bubbling in the SUCTION CONTROL chamber = correct suction function. Vigorous bubbling there does not mean more suction — it means the wall suction is too high. Reduce it.

4. NEVER clamp a chest tube for suspected tension pneumothorax. Clamping increases intrapleural pressure and will kill the patient. The correct action is to unclamp or unseal, call for help, and prepare for emergent decompression.

5. The drainage system must always stay below chest level. Elevating the unit reverses drainage back into the pleural space. This applies during patient transport and transfers.

6. >200 mL/hour of bright red drainage = active hemorrhage. Call the provider immediately. Do not wait for the next assessment.

7. Tracheal deviation AWAY from the affected side + absent breath sounds + hypotension = tension pneumothorax. This is not a tube management failure — it is a medical emergency requiring immediate decompression.

8. Subcutaneous emphysema (crepitus around the insertion site, neck, or face) = air has tracked into soft tissue. Mild and localized is expected; rapid spread indicates ongoing air leak or inadequate drainage.

9. Occlusive dressings: Four-sided seal for closed chest tube sites. Three-sided seal for open/penetrating chest wounds (one edge left open to act as a flutter valve).

10. No dependent loops in the tubing. Fluid in a loop creates back-pressure that impairs drainage. Keep tubing straight and below chest level.

11. Stripping and milking chest tubes is not recommended in most settings. The generated negative pressure can injure pleural tissue. Follow institutional protocol — some cardiac surgery units still use gentle milking for mediastinal tubes.

12. If the drainage unit is dropped or broken, immediately submerge the distal end of the tube in sterile water to preserve the water seal while a replacement is obtained. Never leave the tube open to air.

13. Chest tube removal is performed on Valsalva or full exhalation to minimize air entry at the moment the tube exits the chest. The Vaseline gauze occlusive dressing is applied immediately.

14. Removal criteria: Lung re-expanded on CXR + drainage <50–100 mL/24 hours + no air leak for 24 hours. All three conditions must be met.

15. Post-removal CXR is obtained within 1–4 hours to confirm the lung stays expanded without the tube in place.

Clinical sources

• StatPearls (NCBI). Tube Thoracostomy (Treasure Island, FL: StatPearls Publishing). Available via NCBI Bookshelf. Covers insertion technique, suction parameters, removal criteria, and complications including tension pneumothorax management.
• Chest (journal). BTS guidelines on management of pleural disease, including effusion drainage thresholds and chest tube management recommendations.
• AACN (American Association of Critical-Care Nurses). Procedure Manual for Critical Care, 7th ed. Chest tube management, water-seal mechanics, and drainage assessment protocols.
• Lewis S, Dirksen S, Heitkemper M, et al. Medical-Surgical Nursing: Assessment and Management of Clinical Problems, 10th ed. Elsevier. Standard chest tube nursing care.
• Potter P, Perry A, Stockert P, Hall A. Fundamentals of Nursing, 10th ed. Elsevier. Basic chest tube care and assessment principles.