What is a Perianal Abscess?

A perianal abscess is a collection of pus caused by infection in the tissues surrounding the anus or rectum. Common symptoms may include:

• Pain and swelling around the anus
• Redness of the skin
• Fever
• Pain during bowel movement

Most perianal abscesses require surgical incision and drainage.

The most common cause is infection of the anal glands (cryptoglandular infection).
Several anal glands open into small pits (anal crypts) near the dentate line inside the anal canal. When the opening of a gland becomes blocked, bacteria from the intestine may enter the gland and cause infection, which may lead to abscess formation.

What is an Anal Fistula?

An anal fistula is an abnormal tunnel that forms between the infected anal gland and the skin around the anus.

It usually develops after:

• A perianal abscess ruptures naturally, or
• Surgical drainage of an abscess

The fistula acts like a small tunnel connecting the anal canal to the skin surface. It may cause persistent drainage of pus or fluid.

If the external opening becomes blocked, pus may accumulate again, causing a recurrent abscess. Repeated infections may create multiple branching tracts, making treatment more complex.

Preoperative Precautions

• Fasting is required on the day of surgery.
• An enema or bowel preparation may be given before surgery according to the doctor’s instructions.

After Surgery

Gauze Packing

After surgery, gauze may be placed inside the wound and secured with tape.

You may feel the urge to have a bowel movement. This is normal.

⚠️ Do not remove the gauze by yourself, as this may cause bleeding.

The external gauze is usually removed about 6 hours after surgery according to medical instructions.

Pain

Mild to moderate pain is common for 1–2 weeks after surgery.

Pain relief may include:

• Prescribed pain medication
• Warm sitz baths
• Proper wound care

Difficulty Urinating

Some patients may experience difficulty urinating on the day of surgery due to:

• Pain
• Local swelling
• Gauze packing

This usually improves after the gauze is removed.

Please inform medical staff if urination remains difficult.

Bleeding or Discharge

Small amounts of:

• Blood
• Serous fluid
• Wound drainage

are normal during the healing process.

However, heavy bleeding should be reported immediately.

Sitz Bath

Warm sitz baths help:

• Clean the wound
• Reduce pain
• Promote blood circulation and healing

Recommended frequency:

• Morning，Noon，Evening，Before bedtime
• After each bowel movement

Duration: 3–10 minutes each time

Water temperature: Warm water (about 37–40°C, comfortable to the touch).

If a drainage tube (seton) has been placed, do not soak in a tub. Instead, rinse the area gently with clean water.

Dressing Change and Wound Care

After a sitz bath:

1. Gently pat the wound dry.
2. Apply ointment to your index finger.
3. Insert the finger gently into the anus to a depth of about 1–2 finger joints.
4. Rotate gently to apply the ointment evenly over the wound.

Important notes:

• Do not use cotton swabs instead of your finger.
• Try to apply the ointment yourself rather than asking others for help.
• This helps prevent wound tearing and bleeding.

Apply ointment 2–4 times daily after sitz baths.

If the Wound is from Fistula Surgery

During sitz bathing, gently press around the outer edge of the wound to allow any fluid to drain.

After bathing:

• Pat dry the area
• Cover with clean gauze

Replace the gauze when:

• It becomes wet
• After bowel movement
• After sitz bathing

If a drainage tube (seton) is present:

⚠️ Do not remove it yourself.
The doctor will remove it during a follow-up visit.

Bowel Movement After Surgery

It is normal to feel worried about your first bowel movement after surgery.

Please note:

Bowel movements will not reopen the wound.

Timing

Most patients will have a bowel movement within 1–2 days after surgery.

If you do not have a bowel movement for more than 2 days, consult your doctor.

Prevent Constipation

To keep stools soft:

• Drink 1500–2000 ml of water daily
• Eat foods rich in dietary fiber

Examples include:

Fruits

• Apples
• Papaya
• Dragon fruit
• Kiwifruit
• Tangerines
• Oranges

Vegetables

• Leafy vegetables
• Asparagus
• Bamboo shoots
• Tomatoes

Your doctor may also recommend:

• Stool softeners
• Fiber supplements

During Bowel Movement

Please:

• Relax and avoid straining
• Do not sit on the toilet for too long

Try to finish bowel movement within 5 minutes.

Cleaning After Bowel Movement

After defecation:

• Rinse the anus gently with clean water or
• Take a warm sitz bath

Avoid:

• Vigorous wiping
• Harsh cleaning products

Diet

To maintain smooth bowel movements:

• Eat regular meals
• Increase fruit and vegetable intake
• Drink plenty of water

Avoid:

• Alcohol
• Smoking
• Spicy or irritating foods

Activity Restrictions

Within 2 weeks after surgery, avoid:

• Heavy lifting
• Cycling
• Strenuous exercise
• Prolonged sitting or squatting

Normal daily activities may be resumed gradually.

When Should You Return to the Hospital?

Seek medical attention if you experience:

• Increasing redness, swelling, heat, or pain around the wound
• Heavy bleeding
• Persistent pus discharge
• Fever over 38°C
• Chills

Contact Information

Colorectal and Anal Surgery Clinic
China Medical University Hospital

Telephone: (04) 2205-2121 ext. 16356

Specialized Nurses: 0975-680760, 0975-680767, 0963-620251