The body can do amazing things! From regenerating an organ to healing broken bones, the body can repair itself if given the appropriate environment and medical care.
The following case report describes the successful management of an infected wound in a canine patient treated with surgical debridement and a tie-over wet-to-dry bandage, followed by staged bandage transitions to facilitate second intention healing. The wound demonstrated healthy granulation tissue within 24 hours post-debridement and progressed to complete healing with appropriate wound care management. This report also reviews the physiology of wound healing and discusses indications for primary versus secondary closure.
Signalment and History
A 4-year-old spayed female small mixed breed dog presented for evaluation of a wound on her back. The owners reported that the wound was noticed earlier in the week but didn’t seem to be bothering her. Upon closer inspection the day of presentation, the owners were concerned about bleeding and rupture of a “mass” on the back.
Clinical Findings
The patient was otherwise bright, alert, and responsive upon arrival. Her temperature was elevated at 103.7F (normal 100-102.5F). A scabbed wound with matted fur was found along her back that measured 5cm x 3cm. We were able to shave around the wound and remove the scab to allow us to make treatment recommendations. A necrotic piece of tissue spanned the wound and the wound was covered with a discharge that was yellow in color and had a foul odor. Due to these findings, sedation was recommended to allow us to further explore and clean the wound, remove the dead tissue and determine how best to allow the wound to heal.
Diagnostic Assessment
The wound was classified as contaminated to infected due to:
- Delayed presentation (>24 hours)
- Presence of purulent discharge
- Necrotic tissue
- Bacterial contamination suspected secondary to trauma Given the degree of infection and tissue compromise, primary closure was not recommended at initial presentation.
Therapeutic Intervention
Sedation and Debridement
The patient was sedated, and the wound was clipped and aseptically prepared. Copious lavage was performed using sterile isotonic saline under moderate pressure. Surgical debridement was conducted to remove necrotic tissue and reduce bacterial load.
Bandage Application – Wet-to-Dry Tie-Over
A sterile hypertonic saline-moistened gauze was placed directly over the wound bed and covered with dry sterile gauze and absorbent padding. A tie-over bandage was secured using suture loops placed circumferentially around the wound margins, allowing uniform pressure and easy reapplication.
Wet-to-dry bandages were selected during the inflammatory phase to:
- Mechanically debride devitalized tissue
- Absorb exudate
- Reduce surface bacterial contamination Systemic antibiotics and analgesics were prescribed.
Follow-Up and Outcome
24-Hour Recheck
At 24 hours post-debridement:
- The wound bed displayed healthy, bright red granulation tissue
- No purulent discharge was noted
- Minimal necrotic debris remained The presence of healthy granulation tissue indicated progression into the proliferative phase of healing. The wet-to-dry bandage was discontinued.
Transition to Dry Bandage
A sterile dry, non-adherent dressing was applied to:
- Protect granulation tissue
- Prevent desiccation
- Promote epithelial migration The bandage was rechecked twice at appropriate intervals. Progressive wound contraction and epithelialization were noted at each re-evaluation.
Final Outcome
The wound healed successfully by second intention without complication. Hair regrowth occurred over time, and no functional deficits were observed.
Discussion
Phases of Wound Healing
Wound healing occurs in four overlapping phases:
1. Hemostasis (Immediate)
- Vasoconstriction
- Platelet aggregation
- Fibrin clot formation
2. Inflammatory Phase (0–3 days)
- Vasodilation
- Neutrophil and macrophage infiltration
- Debridement of bacteria and necrotic tissue
Wet-to-dry bandaging is most appropriate during this stage in contaminated or infected wounds.
3. Proliferative Phase (3–21 days)
- Fibroblast proliferation
- Angiogenesis
- Formation of granulation tissue
- Wound contraction
- Epithelialization Healthy granulation tissue is characterized by a moist, red, cobblestone appearance and resistance to infection.
4. Maturation/Remodeling Phase (Weeks to months)
- Collagen remodeling
- Increased tensile strength
- Scar formation
Primary Closure vs. Secondary Closure
Primary Closure (First Intention Healing)
Indicated when:
- Wound is clean or minimally contaminated
- Tissue is viable
- Adequate blood supply is present
- Closure can be achieved without tension
Advantages:
- Faster healing
- Improved cosmetic outcome
- Reduced scar formation
Contraindications:
- Active infection
- Significant contamination
- Devitalized tissue
- Delayed presentation (>12–24 hours for traumatic wounds)
Delayed Primary Closure (Third Intention Healing)
- Wound initially managed open
- Closure performed after infection control and granulation tissue formation (typically 3–5 days)
- Used when contamination is present but sufficient tissue exists for closure
Second Intention Healing
Indicated when:
- Significant tissue loss prevents tension-free closure
- Ongoing infection is present
- Owner declines surgical reconstruction
- Location allows contraction without functional impairment
Healing occurs via granulation tissue formation, contraction, and epithelialization.
Advantages:
- Avoids trapping infection
- No additional surgical procedure required
Disadvantages:
- Longer healing time
- Larger scar
- Potential cosmetic concerns
Clinical Significance
This case highlights several important wound management principles:
- Infected wounds should not be closed primarily
- Thorough debridement and lavage are critical
- Wet-to-dry bandages are useful during early inflammatory stages but should be discontinued once healthy granulation tissue forms
- Transitioning to non-adherent dry bandages protects developing tissue
- Careful monitoring ensures optimal healing progression The rapid formation of healthy granulation tissue within 24 hours suggested effective initial debridement and appropriate wound environment management.
Conclusion
An infected wound in this canine patient was successfully managed through staged wound care, including surgical debridement, wet-to-dry tie-over bandaging, and subsequent dry bandaging. The wound progressed appropriately through the phases of healing and resolved by second intention without complication.
Appropriate wound assessment and selection of closure method are critical to achieving optimal outcomes in veterinary patients. The team at Ruby Veterinary Urgent Care has the experience necessary to evaluate wounds and determine the how best to treat them.