Why is Chronic Wound Healing Difficult?

Chronic wounds are a major health problem worldwide. It is estimated that 1–2% of people in developed countries suffer from chronic wounds at any given time. As the population ages, this number will continue to rise. For example, by 2025, there may be more than 400 million people with diabetes worldwide, of whom 25% will develop diabetic foot ulcers. ^[1]

Chronic wounds refer to those that fail to follow the normal healing process within 3 months, such as diabetic foot ulcers, pressure ulcers, venous leg ulcers, and arterial ulcers. It appears to be stuck in one or more stages of wound healing. The healing process is complex and lengthy, and some chronic wounds may not heal for a lifetime.

Why is chronic wound healing so difficult? Many local and systemic factors are often involved. Understanding the causes of slow healing of wounds is the first step in effective care. This article delves into the complexities of chronic wound healing and offers effective solutions to alleviate it.

The Process of Wound Healing

The difficulties of chronic wound healing are usually caused by being stuck at some stage of wound healing, especially during the inflammation phase. The following is the process of wound healing: ^[2]

1. Hemostasis

When the skin or other tissues are damaged, the body immediately activates the coagulation mechanism. Firstly, the blood vessels constrict, and the wound has platelet aggregation, degranulation, and fibrin to form a thrombus. This is to ensure that the wound does not deteriorate due to excessive bleeding.

2. Inflammation

Inflammation is the body's immune response to injury. First, neutrophils infiltrate to remove necrotic tissue and foreign bodies. As monocytes enter the wound, they differentiate into macrophages that phagocytose necrotic tissue and neutrophil fragments. Subsequently, lymphocytes secrete growth factors to facilitate the transition to the next stages of healing.

The inflammatory phase is the process by which the wound removes necrotic tissue and fights against potential infections. Therefore, prolonged inflammation can delay healing.

3. Proliferation

During the proliferation phase, the endothelial cells and others proliferate and differentiate to form new capillaries, which together form the granulation tissue. Collagen begins to grow within the wound and promotes the wound edges to contract and close.

If infection or inadequate blood supply occur during this phase, the healing process may be impeded.

4. Remodeling

This is the final stage of wound maturation and strengthening. Collagen is remodeling the wound to make it stronger. Blood vessels also mature and degenerate.

If an abnormality occurs at this stage, such as overgrowth of scar tissue or re-injury of the wound, it may result in weak tissue that is susceptible to re-injury.

Types of Chronic Wounds

Any difficulty in chronic wound healing is due to obstacles at the above stages. The following are common chronic wounds :

1. Diabetic Foot Ulcers

Diabetic foot ulcers are caused by chronically high blood sugar in diabetics, leading to neuropathy, poor circulation, and susceptibility to infection. Due to neuropathy, patients may not feel pain or bruising in the foot. Poor blood circulation limits the supply of oxygen and nutrients to the wound.

As a result, the foot becomes ischemic, hypoxic, and edematous and has a reduced ability to heal, making diabetic foot ulcers difficult to heal.

2. Pressure Ulcers

Pressure sores, also known as bed sores, are common in patients with limited mobility.  The constant pressure can hinder blood circulation in local tissues, blocking the flow of nutrients to the body. Localized skin ischemia, lack of oxygen, and lack of nutrients can lead to tissue damage and necrosis.

3. Venous Leg Ulcers

Venous leg ulcers are diseases caused by chronic venous insufficiency, often occurring in the shank. The venous valve insufficiency can interfere with blood return, leading to venous hypertension. Then, blood accumulates in the lower limbs, causing skin nutritional disorders and tissue breakdown.

Due to their complex pathogenesis, venous leg ulcers have a long course and greatly affect the quality of life of patients.

4. Arterial Ulcers

Arterial ulcers occur most often in patients with peripheral arterial disease due to poor arterial blood supply, limiting the oxygen and nutrient supply, which then leads to tissue ischemia and necrosis.

Patients with atherosclerosis are more susceptible to arterial ulcers. Arterial ulcers often occur at the ends of the four limbs, especially the lower legs.

Why Chronic Wounds are Difficult to Heal?

What causes slow healing wounds? There are many slow healing wounds causes. In general, they can be categorized into local and systemic factors.

Local factors are those that affect the wound directly, while systemic factors are general health or disease states that affect an individual's ability to heal. These slow healing wounds causes hinder the chronic wound healing time.

1. Local Factors

Hypoxia: Reduced oxygen supply impedes the metabolism of cells and the formation of new blood vessels.

Infection: Infection is one of the main reasons why chronic wound healing is difficult. Bacteria and other microorganisms can destroy wound tissue, inhibit neovascularization, and lead to chronic inflammation. Therefore, some measures to inhibit infection, such as the use of silver alginate dressings with antimicrobial properties, can protect the wound and inhibit bacterial growth. ^[2]

Pressure: Prolonged or repeated pressure can impair blood circulation to the wound site, reducing the delivery of oxygen and nutrients and hindering healing. Some pressure-relief strategies, such as regular turning and the use of pressure-reducing mattresses, are effective in treating pressure ulcers.

Foreign Bodies: For wounds containing debris, necrotic tissue, or other foreign bodies that can trigger a persistent inflammatory response and slow down the normal healing process, it is recommended to use a Skin and Wound Cleanser. The Skin and Wound Cleanser for prescription use is intended to be used under the supervision of healthcare professionals for cleansing, moistening, and debriding such wounds, creating a more favorable environment for chronic wound healing.

Wound Maceration: Excess exudate not only macerates the skin around the wound, causing symptoms such as wetness, redness, swelling, and pain, but can also lead to infection. Absorbent dressings are able to absorb and retain exudate while maintaining proper moisture on the wound surface. Due to the vertical absorption properties of foam dressings, exudate is effectively controlled, preventing it from coming into contact with the surrounding healthy skin.

2. Systemic Factors

Age: Wounds heal more slowly for older people than for younger people due to the slower regenerative capacity of aging skin. In addition, older people's skin is usually thinner and contains less collagen, which makes them more susceptible to injury.

Chronic Diseases: Diseases such as diabetes and cardiovascular disease affect blood circulation and nutrient supply, leading to reduced tissue repair. For example, chronic hyperglycemia in diabetes can lead to neuropathy, poor circulation, and susceptibility to infection.

Psychological Stress: Many diseases (such as cardiovascular disease, cancer, and diabetes) are associated with stress. Patients with chronic wounds are more prone to high levels of stress. Stress can lead to the immune system as well as endocrine disorders that prolong healing time.

Obesity: Excess weight increases pressure on non healing wounds and impairs circulation. In addition, obese individuals have difficulty or are unable to reposition themselves, further increasing the risk of stress-related injuries.

Medications: Many drugs, such as glucocorticoid steroids, nonsteroidal anti-inflammatory drugs, and chemotherapeutic drugs, interfere with clot formation or platelet function, inflammatory response, and cell proliferation, prolonging the wound healing process.

Nutrition: Malnutrition, especially protein, vitamin, and trace element deficiencies, can cause cellular metabolism to slow down and affect chronic wound healing.

Low Immunity: A compromised immune system reduces the body's defenses against infection, making wounds more susceptible to infection and delaying chronic wound healing.

Smoking and Alcohol: Both impair blood flow and immune response, hindering healing. ^[2]

Overall, research has shown that wound healing is a complex process, and multiple factors can impair chronic wound healing by affecting one or more stages of the process, which can be divided into local and systemic factors. Chronic non healing wounds are more susceptible to these slow healing wound causes, leading to significantly longer healing times. ^[2]

Advanced Chronic Wound Dressings from Winner Medical

Winner Medical is a leading manufacturer of disposable medical supplies. We provide advanced wound dressing solutions for chronic wounds to help patients effectively address local factors affecting chronic wound healing, such as infection, foreign bodies, dryness, and wound maceration, to promote an effective healing process.

FAQs

1. What are chronic wounds?

Chronic wounds are wounds that don't follow the normal healing process and fail to produce anatomic and functional integrity over an extended period of time. They include diabetic foot ulcers, pressure ulcers, venous leg ulcers, and arterial ulcers.

2. What causes slow healing wounds?

The causes of slow healing of wounds include:

lLocal factors like hypoxia, infection, sustained pressure, the presence of foreign bodies, and inadequate moisture.

lSystemic factors such as age, chronic diseases (e.g., diabetes, cardiovascular diseases), psychological stress, obesity, certain medications, poor nutrition, low immunity, and lifestyle habits like smoking and alcohol consumption.

3. How can I tell if a wound is not healing properly?

Signs that wounds are not healing properly include:

lPersistent redness, swelling, or pain around the wound.

lIncreased or continuous discharge of pus or other fluids.

lFoul odor from the wound.

lNo noticeable improvement in wound size or depth over time.

lSigns of severe infection, such as fever or increased warmth around the wound site.

4. What are the best practices for chronic wound care?

The best practices for chronic wound care include the following:

lRegular cleaning and debridement of the wound are necessary to remove dead tissue.

lKeeping the wound moist using appropriate wound dressings.

lManaging wound exudate to prevent maceration.

lProtecting the wound from infection with antimicrobial dressings.

lReducing pressure on the wound area, especially for pressure ulcers.

lEnsuring proper nutrition to support the healing process.

5. How do I choose the right dressing for a chronic wound?

Choosing the right dressing depends on several factors, including the type of wound, the amount of exudate, the presence of infection, and the need for moisture.

Consult with a doctor to decide the best dressing for your specific wound.

6. Can lifestyle changes help in the healing of chronic wounds?

Yes, lifestyle changes can significantly aid in the healing of chronic wounds. These include:

lMaintaining a balanced diet rich in proteins, vitamins, and minerals to support tissue repair.

lQuitting smoking to improve oxygen delivery to tissues.

lReducing alcohol consumption to avoid nutritional deficiencies.

lManaging chronic diseases effectively to prevent complications that hinder chronic wound healing.

lReducing stress through relaxation techniques or counseling.

7. What advanced wound dressings does Winner Medical offer?

Winner Medical offers a range of advanced wound dressings designed to address specific challenges in chronic wound management.

8. When should I seek professional medical advice for a wound?

You should seek professional medical advice if:

lThe wound shows signs of infection, such as increased redness, swelling, warmth, or pus discharge.

lThe wound does not show signs of healing within a reasonable time frame.

lThere is severe pain or an unpleasant odor coming from the wound.

lYou have underlying health conditions, such as diabetes, that could complicate chronic wound healing.

A healthcare professional can provide personalized care and recommend appropriate treatments and dressings.

Conclusion

Overall, chronic wounds won't heal due to the interaction of multiple complex local and systemic factors. Local factors interfere with the normal chronic wound healing process. Systemic factors influence the overall health of the individual and the ability of the wound to heal.

However, through a comprehensive approach, such as the use of advanced wound dressings, infection control, and improved nutrition, an environment more conducive to healing can be created for chronic wounds. Contact Winner Medical to gain effective dressing solutions!

References

[1] Chronic wounds: a rising public health concern. Available at: https://woundsasia.com/journal-articles/chronic-wounds-a-rising-public-health-concern/ (Accessed: 15 August 2024)

[2] Factors Affecting Wound Healing. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2903966/ (Accessed: 15 August 2024)

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