When is a pleural (lung) drain typically removed?

Timing of Pleural Drain Removal

Remove the pleural drain when drainage is less than 200-300 mL per 24 hours in the absence of air leaks, with evidence supporting safe removal at even higher thresholds up to 450-500 mL/day in post-surgical patients. 1

Primary Removal Criteria

The decision to remove a chest drain depends on three key factors that must be assessed together:

Volume Thresholds by Clinical Context

Post-thoracic surgery (lobectomy/VATS):

• Safe removal at <300 mL/24h with no increase in complications or re-intervention rates compared to traditional <100-150 mL/24h thresholds 1
• Higher thresholds up to 450-500 mL/24h are safe and associated with shorter drainage duration (44 vs 67 hours), reduced hospital stay, decreased pain, and lower infection rates 1
• Studies demonstrate only 2.8% re-intervention rates even with high-volume output before removal 1

Malignant pleural effusions (pleurodesis):

• Remove when 24-hour drainage is 100-150 mL/day after talc slurry or poudrage 1
• If drainage remains ≥250 mL/24h after 48-72 hours, repeat pleurodesis before considering removal 1

Pediatric pleural infections:

• Remove based on clinical resolution rather than specific volume thresholds 1
• Consider drainage amount, temperature normalization, general well-being, and imaging findings together 1

Air Leak Assessment

• No air leaks must be present regardless of fluid volume before drain removal 1
• A bubbling chest drain should never be clamped and must remain in place until air leak resolves 1

Fluid Characteristics

• Serous, non-bloody drainage is preferred for safe removal 2
• Protein content matters: drains producing low-protein fluid (pleural/blood protein ratio ≤0.5) can be removed earlier even with higher volumes 3

Timing by Procedure Type

Video-assisted thoracoscopic surgery (VATS):

• Systematic removal at 24-48 hours post-procedure is safe when drainage <350 mL/day, with no air leak 1, 4
• Earlier removal (Day 2) shows decreased postoperative pain without increased re-drainage rates 1, 4

Open thoracotomy:

• Typically requires longer drainage duration (mean 3-4 days) compared to VATS due to higher drainage volumes 1, 4
• Same volume thresholds apply but are reached later in the postoperative course 4

Cardiac surgery:

• Traditional practice removes drains at 100-200 mL/24h, though this lacks robust validation 2
• Character of drainage (serous vs bloody) is more important than volume alone 2

Evidence-Based Algorithm

1. Confirm absence of air leak by observing drainage system 1
2. Measure 24-hour drainage volume:
   • Post-thoracic surgery: Remove if <300 mL/24h (can safely extend to 450-500 mL/24h) 1
   • Post-pleurodesis: Remove if <150 mL/24h 1
   • Pediatric infections: Use clinical resolution as primary guide 1
3. Assess fluid character: Serous, non-bloody preferred 2
4. Obtain imaging if drainage has stopped to rule out loculation rather than true resolution 1
5. Remove drain with single brisk movement during expiration or Valsalva maneuver 1

Critical Pitfalls to Avoid

Do not wait for arbitrarily low volumes (<100 mL/24h) as this unnecessarily prolongs drainage time and hospital stay without reducing complications 1, 5

Never clamp a bubbling drain as this can cause tension pneumothorax 1

Do not remove drain if air leak persists regardless of low fluid output 1

Check for drain obstruction if drainage suddenly stops—flush with 10 mL normal saline rather than assuming resolution 1

Obtain post-removal chest X-ray to detect pneumothorax, particularly in pediatric patients 1

Special Considerations

Size-tailored approach: An individualized threshold of 5 mL/kg/day (rather than fixed 250 mL) leads to shorter drainage duration (2.0 vs 3.3 days) and hospital stay without increased morbidity 6

Protein-guided removal: When pleural fluid/blood protein ratio drops to ≤0.5, drains can be removed earlier regardless of volume, as this indicates transudate that pleura can readily absorb 3

Digital drainage systems may facilitate earlier removal decisions but evidence for superiority over traditional systems remains uncertain 1

Suction vs water seal: No clear advantage of either approach for timing of removal, though some evidence suggests non-suction drainage may shorten overall drainage duration 1