Wound Care and Bandaging: Healing Stages, Dressings, Robert Jones Bandages and Slings

Introduction

A wound is a break in the continuity of a body tissue.⁶ Technicians clip, clean and lavage wounds, place dressings, build bandages and splints, apply slings, and check every bandaged patient on the ward. A bandage that is too tight can cost a patient its limb, so the daily bandage check is one of the most important nursing jobs you will do.

This guide covers the stages of wound healing, lavage and debridement, choosing a dressing, the three bandage layers, Robert Jones and modified Robert Jones bandages, splints, Ehmer and Velpeau slings, tie-over bandages, and bandage complications. The VTNE content outline lists "Perform nursing procedures and maintenance of prescribed treatments (including but not limited to catheterization, wound management, and bandaging)" as Domain 5 Task C.¹

Key facts

How the VTNE tests this

• Name the stage or the layer: match a description to a healing stage, or a material to a bandage layer (Domain 5 Task C; K34 animal nursing procedures).¹
• Choose the dressing: a stem describes the wound bed (necrotic, exudative, granulating, dry) and asks which contact layer fits.
• Choose the bandage or sling: match a Robert Jones, splint, Ehmer, Velpeau or tie-over bandage to an injury and body site.
• Spot the complication: swollen or cold toes, odour, strike-through or chewing at the bandage, and what to do first.
• Lavage details: solution, syringe and needle size, and pressure.

Core concepts

Stages of wound healing

The inflammatory stage starts with hemostasis: vasoconstriction, then vasodilation within minutes. White cells reach the wound within 30 minutes. Neutrophils arrive first; monocytes (macrophages once they leave the vessels) then predominate and are considered essential for healing, because they clear debris and secrete growth factors.²

The proliferative (repair) stage brings fibroblasts, new capillaries and epithelium. In a healthy wound, fibroblasts appear about 3 days after injury. Capillaries and fibroblasts together form granulation tissue, which is friable (bleeds easily) but resistant to infection. Epithelium can cover a properly closed incision within 48 hours, but in an open wound it needs a healthy granulation bed to cross, and it is delayed if the wound dries out.²

The remodeling (maturation) stage reorganizes collagen along lines of tension. It can last up to 2 years, and most healed wounds stay 15% to 20% weaker than the original tissue. Bladder and bone are the exceptions; they regain full strength.²

Source: Merck Veterinary Manual, General Principles of Wound Healing in Small Animals.²

Wound classes and closure

One teaching scheme groups wounds by time and contamination: Class 1 is clean with a 0 to 6 hour duration, Class 2 has significant contamination or 6 to 12 hours, and Class 3 has gross contamination or more than 12 hours. Contamination counts more than time.⁶ First intention healing is primary closure. Second intention healing means the open wound closes by contraction and epithelialization. Delayed primary closure (third intention) is used once a contaminated wound looks clean, after about 2 to 5 days.⁶ Wounds closed more than 5 days after injury are secondary closures.³ The veterinarian decides whether to close a wound; the technician prepares it and manages the bandage.

Lavage and debridement

Lavage (irrigation) washes away debris and lowers the bacterial load. Large volume matters most. A bulb syringe is enough for clean wounds; contaminated wounds need higher pressure, such as a 35 mL syringe with a 19 gauge needle. Too much pressure drives debris deeper. Sterile 0.9% saline is the least toxic fluid. Dilute chlorhexidine diacetate (0.05%) is acceptable; stronger chlorhexidine harms healing tissue. Surgical scrub detergents and hydrogen peroxide must not go into the wound.³

Debridement removes dead tissue and foreign material. Skin that is blue-black, leathery, thin or white is usually not viable. Methods include sharp surgical removal, autolytic (the body's own enzymes under a moist dressing), mechanical (for example bandage debridement), enzymatic and biological (maggot therapy).³

The three bandage layers

The primary or contact layer touches the wound and lets fluid pass outward. The secondary layer absorbs fluid, pads the wound and supports the limb; it is usually cast padding or roll cotton. The tertiary layer holds the inner layers in place, adds pressure and protects them from the environment; it is adhesive tape or elastic wrap.⁴ Conforming (stretch) gauze is wrapped over the padding to hold it and apply even, mild pressure.⁵

Choosing the contact layer

Adherent dressings use wide-mesh gauze that traps debris, which is pulled off at the next change. Dry-to-dry and wet-to-dry (gauze moistened with 0.9% saline) dressings both debride, and both are painful to remove; they also damage healthy tissue because they are nonselective. Wet-to-wet dressings keep the bed too moist.⁴ Nonadherent dressings (fine mesh with petrolatum or a thin polymer coat) do not stick, keep the wound moist and cause little trauma.⁴ Traditional open wound care uses wet-to-dry dressings first, changed at least once daily (up to twice daily early on), then a nonadherent dressing once granulation tissue forms. With moist wound healing, modern dressings support autolytic debridement, and some clinicians now consider wet-to-dry dressings outdated.³

Sources: Merck Veterinary Manual, Wound Bandages and Dressings and Initial Wound Management in Small Animals.³⁴

Bandage types

A Robert Jones bandage reduces soft tissue swelling and stabilizes a fractured limb before repair. It is very bulky: two to three layers of bulk cotton, conforming gauze wrapped with as much tension as possible, then elastic wrap. When flicked, the finished bandage should sound like a ripe melon.⁵ It stabilizes injuries distal to the elbow or stifle.⁷ The modified Robert Jones is smaller: cast padding, stretch gauze and self-adhering tape. It is used more often and allows daily wound care. Without a splint it mainly protects wounds or incisions.⁷

A splint is a rigid strip added between the absorbent and outer layers, usually on the caudal forelimb or lateral hindlimb. A spica splint runs the full length of the forelimb and over the shoulder to the opposite shoulder to immobilize the shoulder and elbow.⁵ A tie-over bandage holds dressings on sites where a limb bandage cannot go, such as the head, flank or inguinal region. Stay sutures are placed in a circle around the wound and umbilical tape is laced through them over the dressing.⁶

Slings

The Ehmer sling holds the pelvic limb flexed with the hip abducted and internally rotated.⁹ It prevents weight bearing and keeps the femoral head seated in the acetabulum after reduction of a coxofemoral (hip) luxation. It puts real pressure over the quadriceps, so watch for muscle damage and check the toes and tibia for swelling.⁵ The Velpeau sling wraps gauze around the thorax and forelimb with the elbow fully flexed and the carpus against the opposite shoulder. It prevents weight bearing after shoulder luxation, scapular fracture or surgery.⁹

Procedure or technique

Applying a padded limb bandage (technician steps)

1. Gather all materials on a clean surface before you start. Place the patient in lateral recumbency with the limb in a normal standing (functional) position, not hyperflexed or hyperextended.⁵⁷
2. Place two tape stirrups, about 20 cm long, on opposite sides of the distal limb, half on the limb and half beyond the toes.⁵
3. Cover any wound with the chosen contact layer.⁵
4. Wrap padding from distal to proximal with 50% overlap. Start at the toes, leaving the third and fourth digits visible.⁵
5. Apply conforming gauze with even, constant, mild tension so there are no high-pressure points.⁵
6. Turn the stirrups back, sticky side to the bandage, then add the elastic outer layer with 50% overlap under firm tension, but not so tight that it blocks lymphatic drainage.⁵ Do not wrap gauze or tape directly onto skin.⁷
7. Never finish with a 360 degree strip of tape around the limb; it acts like a tourniquet.⁵
8. Record the bandage, the time placed and the planned check schedule in the record.

Initial wound preparation

1. Treat the whole patient first; an obvious wound can distract from shock. Control active bleeding with direct pressure.³
2. Fill the wound with sterile water-soluble gel, then clip a wide margin. The gel traps clipped hair.⁶
3. Flush the gel out, scrub the surrounding skin with chlorhexidine scrub, and keep scrub out of the wound.⁶
4. Lavage with a large volume of sterile isotonic fluid at the pressure the veterinarian requests.³
5. Assist with debridement, then cover the wound with a sterile dressing.³

Flowchart: the bandage check

Check every bandage at least twice daily, and any time the patient chews at it or seems painful. Look at the toes, the bandage edges and the bandage itself. If the toes are swollen, spread apart or cold, remove the bandage as soon as possible.⁵ Swelling of the toes under a modified Robert Jones is an emergency; tell the clinician at once.⁶

Bandage complications

Bandages that are too tight cause neurovascular compromise and tissue necrosis, sometimes loss of the limb.⁴ A bandage can tighten after placement if it gets wet or slips.⁵ Other complications are pressure sores over bony points, friction abrasions from a poor fit, and swelling. Replace bandages that become loose.⁷ Wound exudate, urine or feces held against healthy skin cause moisture-associated skin damage (MASD); barrier creams help protect the skin.⁴ For severe arterial bleeding, Merck advises a pneumatic cuff or pressure wrap instead of a narrow tourniquet.³

Species differences

• Dogs: on large dogs the modified Robert Jones layers can be firm, because heavy muscle protects the vessels.⁷ An Ehmer sling finished over the back and around the abdomen cannot be used in male dogs.⁵
• Cats and small dogs: apply the conforming gauze more loosely to avoid nerve and blood vessel damage.⁷ The same bandage principles apply to cats and other companion animals.⁸ The Ehmer sling is used in both dogs and cats.⁹
• Small ruminants and camelids: sheep, goats and alpacas with orthopedic injuries can often be managed like dogs, and most cope on three limbs during recovery, for example with a limb in a Velpeau or Ehmer sling.¹⁰

Calculation

Safety, legal and client education

• Teach owners that the bandage must stay dry, clean and in place, and that visible toes must not swell. Chewing at the bandage, a change in limb use, fever or not eating means a same-day recheck.⁸
• Keep bedding clean and dry and stop the patient stepping in or spilling water onto the bandage.⁶
• Wear gloves when handling fiberglass casting resin; it sticks to skin and gives off heat as it hardens.⁵
• For spica splints and chest wraps, avoid compressing the thorax too much, especially in anesthetized patients.⁵
• Pink and green tape can stain light-coloured fur.⁷
• Bandage type, wound appearance, exudate and every check go in the medical record.

Common mistakes and exam traps

Quick review

1. Healing stages: inflammatory, proliferative (repair), remodeling.
2. Fibroblasts appear about day 3; granulation tissue is pink, friable and infection resistant.
3. Healed wounds stay 15% to 20% weaker; remodeling lasts up to 2 years.
4. Lavage: large volume of 0.9% saline; 35 mL syringe plus 19 gauge needle gives 7 to 8 psi.
5. No hydrogen peroxide or surgical scrub in the wound.
6. Layers: primary contact, secondary padding, tertiary outer wrap.
7. Adherent (wet-to-dry) debrides; nonadherent protects granulation tissue.
8. Robert Jones: very bulky, sounds like a ripe melon; modified RJ is smaller.
9. Tie-over: head, flank, inguinal wounds; stay sutures and umbilical tape.
10. Ehmer sling: hip luxation. Velpeau sling: shoulder luxation or scapular fracture.
11. Leave toes 3 and 4 visible; check at least twice daily.
12. Swollen, spread or cold toes: tell the veterinarian and remove the bandage.