What are the criteria for removing a surgical drain?

Criteria for Removing a Surgical Drain

Surgical drains should be removed when there is clinical resolution, with specific criteria varying by drain type and surgical site, but generally when drainage is less than 300 mL/24h in the absence of air leaks.1

General Principles for Drain Removal

Timing Based on Output Volume

• For most surgical sites, drains can be safely removed when output is less than 300 mL/24h, which has been shown to reduce pain scores, analgesic consumption, drainage time, and length of hospital stay 1
• For thoracic surgery specifically, multiple randomized trials have demonstrated that higher thresholds (up to 450-500 mL/day) for chest tube removal are safe and can allow for earlier drain removal without increasing complications or re-intervention rates 1
• For abdominal drains, removal criteria typically include output less than 200-300 mL/day of non-purulent fluid 1

Clinical Resolution Indicators

• Resolution of signs of infection (decreased fever, improved general well-being) 1
• Normalization of acute phase reactants in blood tests 1
• Radiographic evidence showing resolution of the collection 1
• For chest drains specifically, absence of air leaks is a critical criterion before removal 1

Imaging Confirmation

• Ultrasound or other imaging may be used to confirm absence of significant fluid remaining when drainage has stopped 1
• This helps ensure fluid is not simply loculated and unable to reach the drain tip 1

Specific Criteria by Surgical Site

Thoracic Drains

• Primary criterion: Absence of air leaks 1
• Secondary criterion: Fluid drainage less than 300-500 mL/24h of non-bloody fluid 1
• Systematic drain removal on Day 2 after VATS (video-assisted thoracoscopic surgery) regardless of drainage volume has been shown to be safe with decreased pain and no increase in re-drainage rates 1
• Very early drain removal (on the operating table after extubation) may be feasible in selected patients undergoing thoracoscopy if no air leaks are present 1

Abdominal Drains

• Drainage less than 10-20 cc/day 1
• Resolution of the abscess on repeat imaging 1
• Resolution of signs of infection 1
• For pancreatic surgery, early drain removal (POD 3) is safe in patients with low risk of pancreatic fistula (drain amylase <5000 U/L on POD 1 and 3, and drain output <300 mL/day within 3 days after surgery) 2

Breast Surgery Drains

• Drainage of 40 mL or less during a 24-hour interval 3
• Use of fibrin sealant during surgery may allow for earlier drain removal (average 3.9 days vs 6.9 days) 3

Drain Removal Technique

• Provide adequate analgesia before removal; local anesthetic cream applied to adjacent skin 3 hours before removal has been shown to be effective 1
• For chest tubes, remove either during Valsalva maneuver or during expiration, with a brisk firm movement 1
• For surgically placed drains with closure sutures, approximate the suture while removing the drain 1
• Perform a post-removal imaging study (e.g., chest radiograph after chest tube removal) to ensure no complications such as pneumothorax 1

Common Pitfalls and Caveats

• Blocked drains: Sudden cessation of fluid drainage often indicates obstruction rather than resolution. Check for kinking and consider flushing with normal saline before deciding to remove 1
• Premature removal: Removing drains too early may lead to fluid reaccumulation requiring repeat procedures 1
• Delayed removal: Keeping drains in place longer than necessary increases risk of infection, patient discomfort, and prolongs hospital stay 1
• Inaccurate output recording: Poor documentation of drain output can lead to delayed removal; use standardized drain charts or electronic measurement systems 4, 5
• Drain-dependent infections: Drains left in place for 7-14 days or longer can serve as microbial conduits for pathogens to migrate from the skin to the surgical site 1

Special Considerations

• Surgical approach affects drainage patterns: VATS procedures typically have lower drainage rates than thoracotomy, allowing for earlier drain removal 1
• For drains placed for infected collections, ensure adequate antibiotic coverage before removal 1
• For patients with high risk of bleeding or on anticoagulation, extra caution should be taken when removing drains 1