What is the appropriate management for a patient whose median sternotomy sutures have dehisced?

Management of Sternal Suture Dehiscence

When sternal sutures dehisce after median sternotomy, immediate surgical revision with enhanced fixation techniques is required, combined with negative pressure wound therapy if infection is present, to prevent progression to mediastinitis and reduce mortality.

Immediate Assessment and Classification

First, determine whether this is:

• Superficial dehiscence (skin/subcutaneous only, sternum intact)
• Deep sternal dehiscence (sternal instability without infection)
• Deep sternal wound infection with dehiscence (mediastinitis)

Look specifically for:

• Sternal click or movement with respiration/coughing
• Purulent drainage (present in 92% of infected cases) 1
• Fever, leukocytosis, positive blood cultures
• Sternal fracture lines on imaging (present in 69% of complicated cases) 2

Management Algorithm

For Superficial Dehiscence (Skin/Subcutaneous Only)

Perform surgical debridement with primary closure rather than allowing secondary healing 3. This approach:

• Reduces healing time from 29.7 days to 12.2 days
• Decreases treatment visits from 9.4 to 3.7 per patient
• Works even in contaminated wounds
• Prevents progression to deeper infection

Technique: Extensive debridement of skin and subcutaneous tissue, direct closure of superficial layers, suture removal after 15 days 3.

For Deep Sternal Dehiscence Without Active Infection

Proceed with surgical revision using enhanced fixation techniques 1:

1. Robicsek weave technique (Class IIa recommendation) - especially for:

   • Patients with sternal fractures
   • Obese patients (BMI >30 kg/m²)
   • High-risk patients (diabetes, COPD, bilateral IMA grafts)
   • Reduced dehiscence from 6.15% to 0% in obese patients 1

2. Rigid plate fixation (Class IIb recommendation) - consider for:

   • Multiple sternal fractures
   • Failed previous closure attempts
   • Contraindicated in osteoporosis or active infection 1

3. Standard rewiring with figure-of-eight technique - minimum acceptable approach

For Deep Sternal Wound Infection with Dehiscence (Mediastinitis)

This carries high mortality and requires aggressive multimodal treatment:

Step 1: Surgical Debridement

• Debride all infected tissue without removing bone 4
• Culture-directed antibiotics for 4-7 weeks 5
• Staphylococcus species positive in 92.6% of cases 4

Step 2: Negative Pressure Wound Therapy (NPWT)

• Initiate NPWT whenever delayed closure is anticipated (Class IIa recommendation) 1
• Continue 1-10 sessions (median 4) until cultures turn negative 2
• Critical safety measure: Place protective barrier between sponge and heart/great vessels to prevent fatal hemorrhage from tissue erosion (Class IIa recommendation) 1

Step 3: Definitive Closure

• Use sternal reconstruction with rigid fixation system (plates/bands) 2
• Consider transdiaphragmatic omental flap placement in sternal cavity 2
• Bilateral dissection of skin/subcutaneous tissue as single layer 4
• Double-tube irrigation-suction system (staggered placement anterior and posterior to sternum) 4
• Lateral sternal reinforcement with double-wire closure 4

Step 4: Antibiotic Management

• Avoid dilute povidone-iodine irrigation (Class III recommendation - harmful) 1
• Culture-directed IV antibiotics for 4-7 weeks 5
• Continue until wound healing complete

Expected Outcomes

With proper technique:

• 98% cure rate for mediastinitis with standard protocol 4
• 0% dehiscence rate with preventive enhanced closure in high-risk patients 6
• Zero mortality achievable with aggressive early treatment 4
• Hospital stay approximately 14 days 4

Critical Pitfalls to Avoid

1. Never use povidone-iodine irrigation - increases infection risk (Class III) 1
2. Never apply NPWT without protective barrier over heart/vessels - risk of fatal hemorrhage 1
3. Never use rigid fixation in active infection or osteoporosis - contraindicated 1
4. Never delay surgical intervention for superficial dehiscence - prolongs healing and increases deep infection risk 3
5. Never attempt simple rewiring in patients with multiple sternal fractures or previous failed closure - use Robicsek or rigid fixation 1, 2

Adjunctive Measures

• Maintain glucose <180 mg/dL (Class I recommendation) 1
• Optimize nutrition (correct hypoalbuminemia if present) 1
• External chest support vest postoperatively (Class IIb) 1

The key distinction is that superficial dehiscence requires immediate surgical closure rather than conservative management, while deep dehiscence with infection requires staged treatment with NPWT before definitive reconstruction 1, 4, 3, 2.