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Closure Around Surgical Drains in Dogs and Cats

Closure Around Surgical Drains in Dogs and Cats

Closure Protocol

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Owners

Learn how closure around surgical drains in dogs and cats helps prevent infection and promotes healing after surgery.

By 

Sustainable Vet Group

Updated on

July 17, 2026

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This article is for informational purposes only and is not a substitute for professional veterinary advice. Every case is unique, so always consult your veterinarian for guidance specific to your pet.

This content is intended for veterinary professionals for educational purposes. It does not replace clinical judgment or tailored advice. Always rely on your training, expertise, and the specific context of your patients.

Closure Around Surgical Drains in Dogs and Cats

Surgical drains are not a sign that something went wrong. They are a deliberate clinical decision a way of managing fluid that the body will inevitably produce in response to dead space, contamination, or tissue injury, before that fluid becomes a seroma, abscess, or infection.

The closure decisions made around a drain placement site are as important as the drain itself. Where the drain exits, how it is secured, and how the primary wound is closed relative to the drain all affect whether the drain works as intended.

 

Quick answer: Surgical drains exit through a separate stab incision at least 1 cm from the primary wound closure never through the primary incision itself, as this increases wound dehiscence risk. Passive Penrose drains are secured with 1 to 2 simple interrupted nonabsorbable sutures at the exit site. Active closed-suction drains (Jackson-Pratt) are secured with a purse-string suture at the exit and a Chinese finger-trap suture to prevent migration. The primary wound is closed normally in layers above and around the drain.

 

Key takeaways

  • Drains exit through a separate stab incision, not through the primary wound this protects the primary closure from dehiscence.
  • Passive Penrose drains are secured at the exit with 1 to 2 simple interrupted nonabsorbable sutures.
  • Active Jackson-Pratt drains use a purse-string exit seal and Chinese finger-trap suture for secure fixation.
  • The exit site is not sutured closed at removal it heals by second intention.
  • Drains typically remain 2 to 7 days depending on output volume and color.
  • Never fenestrate a Penrose drain this reduces surface area for capillary drainage and increases tearing risk at removal.

When drains are placed

Drains are placed when the surgeon cannot eliminate dead space through suturing alone, or when significant contamination or fluid production is expected post-closure.

Common indications:

  • Large dead space after mass excision (tumor removal, extensive soft tissue dissection)
  • Contaminated wounds where seroma infection risk is high
  • Seroma or abscess drainage after established fluid pockets
  • Abdominal drainage after peritonitis, bile peritonitis, or uroabdomen

For how dead space elimination through suturing reduces the need for drains, see dead space management and when drains are needed. For how proper drain placement prevents seroma formation, see seroma prevention with drain placement.

Passive vs. active drains

Passive drains (Penrose)

A flat latex tube that relies on gravity and capillary action to draw fluid from the wound to the external exit. Fluid seeps along the outer surface of the tube.

Properties:

  • Works by gravity and capillary action must exit at the most dependent (lowest) part of the wound pocket
  • Requires an open exit (not sealed) to function
  • Simple, inexpensive, easily placed
  • Higher risk of retrograde bacterial contamination than active drains keep the exit covered with a sterile bandage

DVM360: "Passive drains need to exit at the most dependent part of the wound or abscess pocket and must be covered at all times."

Active drains (Jackson-Pratt, closed-suction)

A perforated tube connected to a sealed collection reservoir that maintains gentle negative pressure, actively pulling fluid from the wound.

Properties:

  • Works independently of gravity can be positioned in locations where passive drainage would fail
  • Closed system lower bacterial contamination risk
  • More expensive; requires a functional reservoir
  • Better for high-volume drainage or wounds in areas of high movement (axilla, groin)

Clinician's Brief: "Active drains are secured with a purse-string suture to create a seal and a finger-trap suture to hold it in place."

Drain placement technique: where the exit goes

The drain exit site is not through the primary incision. It must be separate.

Clinician's Brief (Wound Drain Placement): "Exit the drain through a separate incision at least 1 cm from the primary suture line. Exiting drains through the primary incision line increases the risk for wound dehiscence."

DVM360 (Surgical Drains in Small Animal Wound Management): "It should not exit along the lines or within the plane of wound closure, as this may provide an entry point for bacteria or may result in dehiscence and additional drainage along the suture line."

Stab incision technique:

  1. With the primary wound fully closed, the surgeon uses hemostatic forceps to tunnel subcutaneously from the wound cavity to the planned exit point
  2. A scalpel stab incision is made over the tip of the forceps at the exit site
  3. The drain is pulled through the stab incision to the external surface
  4. The drain is secured with exit sutures

The stab incision is sized to match the drain diameter tight enough that the drain does not slide freely but not so tight that it impedes drainage.

How drains are secured: suture technique at the exit

Penrose drain

DVM360: "1 or 2 simple interrupted nonabsorbable sutures are placed through the drain and into the skin at the exit hole."

The suture passes through the drain material itself and through the skin, holding the drain at the correct depth. The suture should be placed through the last 1 mm of the drain on one side securing it without impeding drainage flow or making removal difficult.

Important: tacking the proximal (deep, internal) end of the Penrose drain inside the wound is done cautiously. DVM360 cautions: "Tacking the proximal aspect of the Penrose drain can only be considered with caution, as this can create a natural tension causing potential for drain breakage deep inside the wound."

Do not fenestrate the Penrose drain. Vettimes: "The drain should not be fenestrated as this will reduce the surface area for capillary flow and increase the risk of tearing at the time of removal."

Jackson-Pratt drain (closed suction)

Two-suture fixation:

  1. Purse-string suture at exit: a circular suture around the drain at the exit site, tightened to create a seal around the drain and prevent leakage
  2. Chinese finger-trap suture: a wrapping pattern along the external portion of the drain tubing, providing robust fixation that resists the pull of the collection reservoir

Clinician's Brief notes the Chinese finger-trap suture should be easily distinguishable from the primary wound sutures, so it is not accidentally cut at suture removal time.

Primary wound closure around the drain

The primary wound is closed normally in layers subcutaneous closure, then skin above and around the drain, which runs out to its separate exit site.

Key principle: the drain does not pass through any of the primary closure layers. The wound closes completely around the drain, which then tunnels subcutaneously to its separate exit.

For how drain placement relates to the layered closure sequence, see drain placement in layered closure context.

Monitoring drain output at home

VCA Animal Hospitals: "Fluid should be draining from the Penrose drain's end, but the fluid amount should decrease every day. There should not be excessive fresh blood, active bleeding, or increasingly unpleasant, thick, or smelly discharge."

Normal drain output progression:

  • Days 1 to 2: serosanguinous (blood-tinged watery fluid), moderate volume
  • Days 2 to 4: decreasing volume, clearing toward serous (pale yellow or clear)
  • Days 4 to 7: minimal volume, fully serous drain is ready for removal

Signs requiring same-day vet contact:

  • Volume increasing rather than decreasing after day 2
  • Output becoming purulent (thick, green, or yellow) or foul-smelling
  • Fresh active bleeding from the drain
  • Drain pulled inward (disappearing under the skin) or pulled outward (partially extruded)

For the post-operative monitoring protocol that includes drain assessment, see post-operative monitoring with drain in place.

Drain removal

Timing: VCA: "Drains should be removed as soon as possible, usually within 2 to 4 days. For larger, more extensive wounds, drains may need to stay in place longer."

Most soft tissue drains are removed at 2 to 7 days. Abdominal drains after peritonitis may remain longer depending on drainage character.

Removal technique:

  • Penrose: cut the exit suture(s), pull the drain out with a swift, smooth traction
  • Jackson-Pratt: cut the Chinese finger-trap suture, disconnect the reservoir, slide the drain out

Vettimes: "Penrose drains are removed by cutting the single external simple interrupted suture, then swiftly tugging the drain to release the tube from its internal anchorage point."

After removal: the exit hole is not sutured. It heals by second intention typically within 3 to 5 days. Keep the area clean with saline until sealed.

Verify complete removal: count the drain length removed against the length inserted. A retained drain fragment is a serious complication requiring surgical retrieval.

Frequently asked questions

My dog has a drain coming from a separate hole next to the incision. Is that normal?

Yes that is the intended placement. The drain exits through a stab incision separate from the primary wound closure. Having the drain exit away from the main incision protects the primary wound from dehiscence and contamination. Both the main incision and the drain exit site should be monitored.

Can my cat remove the drain at home?

Cats frequently attempt to remove drains. An E-collar must be worn at all times until the drain is removed by the vet. Even with an E-collar, some cats are agile enough to reach wounds check drain integrity twice daily. If the drain has been dislodged, contact your vet the same day.

Why doesn't the vet just suture the drain hole closed after the drain comes out?

The exit tract is left to heal by second intention because suturing it closed traps any residual fluid or bacteria that may be present in the tract. Healing open allows this to drain and epithelialize naturally. The resulting healed site is typically a small, flat scar.

Surgical drains work only when the closure around them maintains what the drain is trying to accomplish: fluid exits through the drain, not through a compromised wound closure. The separate exit site, the correct fixation sutures, and the correct coverage all of these protect both the drain's function and the primary wound's integrity simultaneously.

Resources

  • Clinician's Brief. Wound Drain Placement: Step-by-Step Veterinary Guide. cliniciansbrief.com
  • DVM360. Surgical Drains Are Useful in Small Animal Wound Management. dvm360.com
  • Today's Veterinary Practice. Surgical Drains: Placement, Management, and Removal. todaysveterinarypractice.com
  • VCA Animal Hospitals. Penrose Drain Discharge Instructions for Dogs. vcahospitals.com

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Step #1

Getting Ready

Ensuring a clean surgical field starts with proper skin preparation. This video demonstrates the best practices for:

  • Shaving the patient – Achieving a close, even shave while minimizing skin irritation
  • The Dirty Scrub – The initial skin prep step to remove surface debris and reduce bacterial load before the sterile scrub.

Following these techniques helps reduce infection risk and improve surgical outcomes. Watch the video to see how it’s done effectively!

Step #2

Reduce Your Risks

Many surgeons are shocked to find out that their patients are not protected from biofilms and resistant bacteria when they use saline and post-op antibiotics.

That’s Where Simini Comes In.

Why leave these risks and unmanaged?  Just apply Simini Protect Lavage for one minute. Biofilms and resistant bacteria can be removed, and you can reduce two significant sources of infection.

Step #3

Take the Course

Preventing surgical infections is critical for patient safety and successful outcomes. This course covers:

  • Aseptic techniques – Best practices to maintain a sterile field.
  • ​Skin prep & draping – Proper methods to minimize contamination.
  • ​Antibiotic stewardship – When and how to use perioperative antibiotics effectively.

Stay up to date with the latest evidence-based protocols. Click the link to start learning and earn CE credits!

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