# Clinical Cases: Surgical Wound Healing

## 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
![Surgical Site Infection](case_01_image.jpg)

**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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## Case 2: Keloid Formation Following Sternotomy

### Patient Demographics
- **Age:** 42 years
- **Sex:** Female
- **Occupation:** Marketing executive
- **Ethnicity:** African American

### Chief Complaint
"The scar from my heart surgery keeps growing and is painful."

### History of Present Illness
The patient underwent mitral valve repair via median sternotomy 18 months ago for severe mitral regurgitation. The initial wound healed uneventfully, but over the past year, she has noticed progressive enlargement of the scar tissue, which now extends beyond the original incision line. The scar is raised, firm, and causes significant itching and occasional sharp pain. She is self-conscious about the appearance and has difficulty wearing low-cut clothing.

### Past Medical History
- Mitral valve prolapse with severe regurgitation (repaired)
- Family history of keloid formation (mother and sister)
- Previous keloid formation after ear piercing (age 16)

### Physical Examination
**Scar Examination:**
- Midline chest scar extending 15 cm from sternal notch to xiphoid
- Keloid formation extending 2-3 cm beyond original wound margins
- Firm, raised, nodular texture
- Hyperpigmented with erythematous areas
- Tender to palpation
- No signs of infection

**Comparison to Hypertrophic Scar:**

| Feature | This Patient (Keloid) | Hypertrophic Scar |
|---------|----------------------|-------------------|
| Extends beyond wound | Yes (2-3 cm) | No |
| Spontaneous regression | Unlikely | Often improves 1-2 years |
| Recurrence after excision | High (>50%) | Lower |
| Risk factors | Darker skin, genetic | Wound tension, location |

### Diagnosis
**Keloid scar formation following median sternotomy**

### Treatment Options Discussed

**1. Intralesional Corticosteroid Injection:**
- First-line therapy
- Triamcinolone acetonide 10-40 mg/mL
- Monthly injections for 3-6 months
- Mechanism: Reduces collagen synthesis, increases collagenase activity

**2. Silicone Gel Sheeting:**
- Adjunctive therapy
- Worn 12-24 hours daily for 3-6 months
- Mechanism: Hydration, pressure, unknown factors

**3. Pressure Therapy:**
- Difficult to apply to sternotomy site
- Custom pressure garments available

**4. Combination Therapy:**
- Surgical excision + immediate intralesional steroids + radiation
- Reserved for refractory cases due to recurrence risk

### Treatment Plan Initiated
1. Intralesional triamcinolone 40 mg/mL monthly x 6 treatments
2. Silicone gel sheeting 12 hours daily
3. Reassessment at 6 months

### Follow-up (6 months)
- 50% reduction in keloid height and firmness
- Itching and pain significantly improved
- Continued monthly injections recommended
- Patient satisfied with improvement

### Teaching Points
1. Keloids extend beyond original wound margins (key distinguishing feature)
2. Genetic predisposition common, especially in darker-skinned individuals
3. High recurrence rate (>50%) with surgical excision alone
4. Multimodal treatment most effective
5. Prevention in high-risk patients: avoid unnecessary surgery, use tension-free closures, early silicone therapy