Contributors: Alasdair Hotston Moore

 Species: Canine   |   Classification: Techniques

Introduction Requirements Preparation Procedure Aftercare Outcomes Further Reading


  • To remove unwanted material from tissue spaces.


  • Obliteration of dead space.
  • Elimination of subcutaneous collection of fluid (seroma Seroma , hematoma, pus) and gas.
  • Provide prophylaxis against anticipated fluid or gas accumulations, particularly in the presence of contamination.


  • Easy to place and maintain.
  • Cheap.


  • Increased infection rates compared with wounds in which drains are not placed.
  • Drain can act as a foreign body, causing irritation and interfering with wound healing.

Technical Problems

  • Inappropriate use of drain.


  • Few minutes in addition to usual wound closure procedures.

Decision Taking

Criteria for choosing test

  • Large dead space.
  • Subcutaneous collection of fluid.
  • Potential for accumulation of fluid or air, particularly in the presence of wound contamination.


Materials Required

Minimum equipment

  • Skin suture instruments.
  • Aseptic dressing.
  • Skin suture material Suture materials.

Minimum consumables

  • Drain.

Passive drain

  • Drain by capillary action and gravity.
  • Drainage occurs outside lumen.
  • Drainage efficiency is directly related to surface area of drain.
  • Fenestration contra-indicated because decreases surface area and impedes flow.
  • Soft latex or similar, eg Penrose drain Drain: Passive (Penrose).

Active drain Drain: active (tube)

  • Rubber or plastic.
  • Round with single lumen +/- side holes.
  • Remove fluid by application of a vacuum.
  • Various commercial kits are available and tend to be preferable to homemade devices.
  • Advantages:
    • Fluid collected cleanly into a chamber.
    • Irrigation possible.
    • Less interference with healing than Penrose drains.
    • Tend to be better tolerated by the patient.
    • Position of drain can be chosen without regard to the effect of gravity.
  • Disadvantage: more expensive than passive drains.

Sump drain

  • Large drainage lumen and smaller inner sump lumen to allow air to displace fluid into the drainage lumen.
  • More efficient and maintain efficiency longer than single lumen drains.
  • Foley catheter can be modified by removing bulb and making side holes in large tube.
  • Disadvantages: air sucked into the wound may be contaminated, greater bulk of drain more likely to irritate tissues.


Site Preparation

  • Prepare wound according to principles of wound care.
  • Include site for drain exit in the surgical field.
  • Drain is usually placed prior to closure, although active drains can be placed percutaneously into collections of fluid.


  • General anesthesia.

Other Preparation

  • Prophylactic antibiotics (continue for at least 24 h after removal of drain).



Step 1 - Incise skin

  • Passive drain Drain: Passive (Penrose) : make stab incision slightly larger than size of drain below wound.
  • Active drain Drain: active (tube) is supplied commercially with an attached Alleyn needle, which is used to bring the outer end through the skin at a convenient position away from the wound. Therefore skin incision is not required at this time.

Step 2 - Place drain into wound


  • Drain is placed with one end within the wound cavity. This end may be secured, with a simple absorbable suture taking a bite of tissue and catching the tip of the drain (such that the drain can be pulled out later and will tear away from the suture), or by a suture placed through the skin, through the tip of the drain and back out through the skin to be tied on the surface. This suture should be clearly marked and then can be cut when the drain is removed. Although some clinicians place the drain so that it is secured dorsally with a suture at a stab incison (so the drain is through and through the wound cavity) this increases the potential for contamination. Bring end of drain out through skin in a dependant position through a stab incision (not the primary incision) and secure here with a skin stitch. Close the wound routinely.

Active drain

  • Drain is placed with the fenestrated end within the wound cavity (ensure all holes are under the skin). Use the Alleyn needle attached to the other end to tunnel the drain out through the skin to exit at a site away from the wound and positioned to avoid patient interference (eg near dorsal midline). Secure the drain at the exit with a Roman sandal suture. Close the wound routinely, ensuring an airtight seal.

Core Procedure


Step 1 - Dress drain

  • Active drains usually need no dressing, except to fasten the chamber to the animal, eg a stockinette jacket. Wherever possible, passive drains should be covered at the exit with sterile absorbent material to contain the exudate and prevent ascending infection.



Antimicrobial therapy

  • Prophylactic antibiotics for at least 24 h after removal of drain.

Wound Protection

Remove drain

  • Capillary ooze only: remove within 24 h.
  • Profuse serum discharge: remove within 3-4 days.
  • Large areas of dead space: up to 10 days until dead space obliterated.

    Prolonged use of drains may lead to discomfort, infection and cellulitis.

Potential complications

  • Ascending infecton.
  • Cellulitis.
  • Incisional dehiscence.


Reasons for Treatment Failure

  • Inappropriate use of drain.
  • Lack of sterility.

Further Reading


Refereed papers

Other sources of information

  • Manual of Canine and Feline Wound Management and Reconstruction. (1999) Eds. Fowler D and Williams JM BSAVA, Cheltenham.
  • Small Animal Wound Management(2nd Edition) (1997) Swaim SF and Henderson RA. Williams and Wilkinson, Baltimore.