General Surgery · Year 3 · from General Surgery

Case 1: Surgical Site Infection and Wound Dehiscence

Patient Demographics

  • Age: 64 years
  • Sex: Male
  • Occupation: Truck driver

Chief Complaint

"My incision is opening up and draining pus."

History of Present Illness

The patient underwent open right hemicolectomy for colon cancer 10 days ago. He was discharged on postoperative day 5 with a healing midline incision. He presents today with a 2-day history of increasing incisional pain, fever, and foul-smelling drainage from the wound. He noticed the wound edges separating this morning with purulent material visible. He denies abdominal distension, nausea, or vomiting. He has been passing flatus and having small bowel movements.

Past Medical History

  • Colon adenocarcinoma (T3N0M0) - right colon
  • Type 2 diabetes mellitus (HbA1c 8.5%)
  • Obesity (BMI 34)
  • Hypertension
  • 40 pack-year smoking history (ongoing smoker)

Surgical History

  • Open right hemicolectomy 10 days ago
  • Appendectomy age 25

Medications

  • Metformin 1000 mg twice daily
  • Glipizide 10 mg twice daily
  • Lisinopril 20 mg daily
  • No prophylactic antibiotics at discharge

Physical Examination

  • Vitals: BP 142/88 mmHg, HR 102 bpm, Temp 38.6C, RR 18/min
  • General: Obese male, uncomfortable but not toxic-appearing
  • Abdomen: Soft, non-distended, midline incision with 6 cm dehiscence in the mid-portion
  • Wound examination:
  • 6 cm separation of skin and subcutaneous tissue
  • Purulent drainage (thick, yellow-green)
  • Surrounding erythema extending 3 cm from wound edges
  • Fascial layer intact on probing
  • No exposed bowel or evisceration
  • Necrotic subcutaneous fat at wound edges

Laboratory Results

  • WBC: 18,200/uL with left shift (85% neutrophils, 8% bands)
  • Glucose: 245 mg/dL
  • Creatinine: 1.1 mg/dL
  • Lactate: 1.4 mmol/L

Wound Classification

  • Original surgery: Class II (Clean-Contaminated) - controlled entry into colon
  • Current wound: Class IV (Dirty-Infected) - established infection with purulence

Diagnosis

Superficial surgical site infection with partial wound dehiscence

Risk Factors Present

  1. Diabetes with poor glycemic control
  2. Obesity
  3. Active smoking
  4. Clean-contaminated wound class
  5. Malignancy (immunocompromised state)

Management

Immediate Treatment:

  1. Wound cultures obtained (aerobic and anaerobic)
  2. Wound opened completely to allow drainage
  3. Necrotic tissue debrided at bedside
  4. Wound packed with saline-moistened gauze
  5. IV antibiotics initiated (piperacillin-tazobactam)
  6. Tight glycemic control with insulin drip (target glucose 140-180 mg/dL)

Wound Care Plan:

  • Twice daily wet-to-dry dressing changes
  • Decision for secondary intention healing given superficial infection
  • Wound VAC therapy considered if wound bed remains clean

Wound Culture Results:

  • Escherichia coli (sensitive to piperacillin-tazobactam)
  • Bacteroides fragilis (sensitive to piperacillin-tazobactam)

Hospital Course

  • Fevers resolved within 48 hours
  • WBC normalized by day 3
  • Antibiotics transitioned to oral amoxicillin-clavulanate on day 4
  • Wound showing healthy granulation tissue by day 5
  • Discharged day 6 with home wound care and visiting nurse

Follow-up (6 weeks)

  • Wound healed by secondary intention
  • Total healing time: 8 weeks
  • Resulting scar wider than primary closure would have been
  • No fascial hernia on examination
  • Counseled extensively on smoking cessation

Clinical Image

Image Description: Clinical photograph demonstrating a surgical wound infection with surrounding erythema and wound dehiscence. Signs of infection include purulent drainage, erythema extending beyond wound margins, and tissue necrosis.

Attribution: Image from Wikimedia Commons, licensed under CC BY-SA 3.0. Source: https://commons.wikimedia.org/wiki/File:Surgical_wound_infection.jpg

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