Penrose Drain Discharge Instructions for Cats

By Malcolm Weir, DVM, MSc, MPH; Rania Gollakner, BS DVM

What is a Penrose drain?

A Penrose drain is a latex tube placed into a wound with one or two ends exiting the skin, allowing fluids to drain from the wound. The drain is typically sutured to the skin to hold it in place. Typically, the drain will exit from a new incision site, not the primary wound site.

The Penrose drain is designed to passively remove unwanted fluid, usually when treating abscesses or open wounds. Abscesses and open wounds are considered contaminated, and removing unwanted fluid and pus via the drain helps the wound heal.

What should I do when my cat arrives home?

Your cat should be kept indoors to prevent the wound area from getting dirty. Activity (such as running and jumping) should be kept to a minimum to avoid strain and damage to the wound site.

What do I need to know if my cat received anesthesia to place the drain?

Your cat may be sleepy for 24-48 hours after the procedure. Some cats can feel nauseated after anesthesia, so offer only small amounts of food and water. If your cat does not vomit after an hour, you can continue to offer small meals and free choice of water over the next 24 hours before returning to regular feedings.

Contact your veterinarian if lethargy or lack of appetite lasts more than 24 hours after anesthesia or if vomiting or diarrhea occurs. A mild cough for a few days can occur if your cat was under general anesthesia, but if the cough persists or worsens, please contact your veterinarian.

What should I do if my cat is licking or chewing at the drain site?

An Elizabethan collar (E-collar or cone) should be placed on your cat to prevent chewing and licking the wound. A clean bandage may also cover the drain to absorb the fluid and protect the wound from contamination with debris such as dirt or hair. Your cat may try to remove the E-collar at first, but most cats will get used to the collar and tolerate wearing it. It is better to use the E-collar than risk your cat damaging the surgery site or ingesting bandage material.

Do I need to change the bandage?

If there is a bandage, it should be changed frequently enough so that the draining fluid does not saturate the bandage. Therefore, how often the bandages need changing depends on the amount of fluid draining. As the wound heals, the amount of fluid draining from the Penrose drain should decrease.

Should I apply any medications to the wound?

No. You should not apply any medications to the wound or draining areas unless recommended by your veterinarian. To avoid irritation to the intact areas of skin under the drain edges, a light layer of Vaseline® or triple antibiotic ointment can be applied to protect the skin. The site where the drain exits should be cleaned daily with chlorhexidine or another appropriate cleanser to maintain drainage. Cleaning the draining material off the skin regularly will also help prevent skin irritation. Your veterinarian will provide specific instructions for cleaning and ointments.

"You should not apply any medications to the wound or draining areas unless recommended by your veterinarian."

Will my cat receive any medications after surgery?

Your cat may be sent home with pain or other oral medications, such as antibiotics. If you have been given medications, please read the label carefully to ensure that you administer all medications correctly. If antibiotics are prescribed, it is essential to finish the entire prescription.

What should the drain site look like, and when should I be concerned?

There should be a small opening where the drain exits the skin, but the skin edges should be closed at all other incision sites. The drain should not disappear under the skin and should remain sutured in place. The skin around any incisions may be a normal color to slightly reddish. There may be mild swelling of the skin. Fluid should be draining from the Penrose drain's end, but the fluid amount should decrease daily.

Depending on the reason for the drain, the fluid may vary in color and consistency, but there should be no excessive fresh blood, active bleeding, or increasingly unpleasant, thick, or smelly discharge. There should be no excessive redness or swelling of the skin. Contact your veterinarian immediately if you observe any of the above.

When should the drain be removed?

Drains should be removed as soon as possible, usually within two to four days. Drains may need to stay in place longer for more extensive wounds. A drastic decrease in the amount of draining fluid signifies that the drain is ready to be removed. Your veterinarian will provide specific instructions about how long the drain needs to remain in place.

When can my cat resume normal activities?

Once the drain and all sutures have been removed, your cat can return to normal activities unless directed otherwise by your veterinarian. Your cat should not be bathed until all sutures have been removed and the drain openings have closed completely.

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