Why Moisture is Critical in Wound Healing
Although hydration is today considered an essential technique for optimal wound healing, allowing wounds to dry out was the standard practice until the early 1960s. Compared with dry healing, moisture facilitates faster epithelialization, reduces pain, and long-term scarring as skin layers repair more rapidly. This article discusses the role of moisture in wound healing, benefits, challenges, and contraindications.
Benefits of Moist Wound Healing
The main benefits of maintaining an optimal moist healing environment are less pain for the patient and reduced long-term scarring in the wounded area. However, good moisture management also provides the following benefits:
- Increases wound healing rates (up to 50% faster in most cases)
- Lowers the risk of infection and minimizes the need for antibiotics
- Facilitates angiogenesis (development of new blood vessels)
- Stimulates collagen synthesis
- Increases the rate of cellular migration
- Improves healing outcomes (lower risk of limb amputation, wound infection, and death)
Creating a Moist Wound Healing Environment
The most effective way to ensure proper hydration in chronic wounds is via advanced wound care dressings that donate moisture to the wounded area while minimizing drainage and limiting fluid levels. An ideal dressing should have the following qualities:
- Medium to high absorbency to remove excess exudate
- Non-toxic and hypoallergenic
- Prevents bacterial intrusion by acting as a barrier between the skin and environment
- Able to be removed without causing trauma to the wound bed and periwound skin
- Conformable to the shapes of various body parts
- Allows for gaseous exchange between the wound bed and the environment
Wound dressings need to be changed from time to time. The frequency usually depends on the nature of the wound and the quantity of exudate produced.
Wound Dressings for Optimal Moisture Management
Wound care dressings suitable for maintaining optimal moisture balance include hydrocolloids, films, hydrogels, foams, and alginates. Let's take a closer look at how each dressing works.
Film: Semi-permeable film dressings consist of non-toxic, hypoallergenic, transparent films made from polyurethane. They help to retain moisture in the wound bed and allow for gaseous exchange while being impervious to external fluids and bacteria.
Hydrogels: Hydrogels are water-based dressings capable of donating moisture to dry wounds. They are available in sheet or amorphous forms, often containing antimicrobial agents that help prevent wound infections.
Foams: Due to their highly absorbent nature, foams promote an optimal moist environment in low to heavy-drainage full and partial thickness wounds. Like hydrogels, foam dressings may also contain antimicrobial agents to prevent wound infections.
Hydrocolloids: These types of dressings consist of gel-forming substances such as pectin, carboxymethyl-cellulose, and gelatin. They are available in solid or amorphous forms and help to improve moisture retention in dry to medium draining wounds and also to prevent infection.
Alginates: Alginates are biodegradable wound dressings made from natural fibers, such as seaweed. Alginate dressings have high absorbent properties (up to 20 times their weight in exudate), making them ideal for donating moisture to medium to heavy-draining wounds.
Challenges with Moisture Management in Chronic Wounds
Improper moisture management can complicate the wound healing process in several ways. The main challenges wound care professionals face are preventing maceration and tissue degradation.Maceration occurs when wounds are exposed to moisture or drainage (exudate) for long periods. Macerated skin appears whiter in color than the rest of the body, soggy, and wrinkly. Where the wound is located on the body, patients' age, skin type, and underlying skin conditions can contribute to the risk of macerations.
If macerations are left untreated, they can affect patients in the following ways:
- Causes pain and discomfort
- Increases the risk of bacterial or fungal infection
- Can result in tissue damage and necrosis
- Can result in skin conditions such as dermatitis and weeping eczema
To prevent macerations, professionals need to maintain an ideal balance of moisture in patients. The most effective way is by addressing the root causes. For example, macerations in heavy draining wounds are caused by large volumes of exudate. Thus, using an absorbent wound dressing can help to reduce the moisture content. It is also necessary to perform regular inspections to identify any early signs of macerations.
Contraindications of Moist Wound Healing in Patients
While a moist environment can improve wound healing outcomes, there are cases where it is unsuitable, and alternative treatment techniques are advisable. Hydration techniques are not suitable for treating the following types of wounds:
- Fungating wounds (caused by tumor infiltration to the skin due to cancerous cells)
- Wounds in patients undergoing palliative care
- Wounds due to calciphylaxis (a condition where there is an accumulation of calcium in fat and skin tissues)
- Ischemic or neuropathic ulcers
- Wounds resulting from meningococcal disease (a severe case of blood poisoning that affects the entire body)