Wounds

Our skin is the largest organ of the body. It protects us by providing a barrier to infection and providing sensory stimulus. It also helps to regulate our temperature and synthesizes important vitamins.

It has three basic layers Epidermis, Dermis and the subcutaneous layer.

Occasionally skin becomes damaged either through a traumatic event, surgery or lack of nutrition. Loss of tissue for whatever reason is considered a wound.

Most wounds normally heal within 4-14 days with little intervention. It is not necessarily an indicator of a problem in the healing process if a wound does not heal within a certain timeframe as long as progression is being made. The stages of wound healing are:

Homeostasis; blood flow is stemmed by clotting mechanisms
Inflammation; the capillaries increase in permeability to allow nutrients and growth factors to start the healing process
Proliferation; new base tissue begins to form
Maturation; the area is remodeled with new finishing tissue

Sometimes wounds do not follow normal healing patterns. There are a number of reasons why this may occur:

Lack of nutrition to the wound
A lack or imbalance in growth factors or chemicals
Bacteria in the wound

Contributory factors to delayed healing can be:

Age
Nutrition
Type of medication being taken
Diabetes
Smoking

Modern wound dressings are designed to create the most favorable environment for wounds to heal. They are selected according to the needs of the patient, anatomical site, the stage of wound healing and any underlying issues.

It is important to be able recognize the stage a wound is at in the healing phase and to know if a wound is not following the normal progression in healing. Identifying debris in the wound and knowing how best to deal with it are important aspects of wound management. Preserving viable tissue and structures within the wound bed will assist the healing process.

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It has been known since 1962 (Winter) that maintaining a moist wound healing environment promotes faster healing and may result in an improved cosmetic outcome.

It is important to remove any debris from a wound and ensure a balanced moist environment that may impair the healing process. Dry necrotic tissue can harbor bacteria and prevent the function the natural healing processes. Yellow puss (slough) will also provide nutrition for bacteria which damage newly formed tissue and delay healing. Excessive exudate will macerate tissue and cause cell lysis (death). Bacteria in wounds can result in malodour and affect the seriously affect the patients quality of life. In severe cases bacterial infection can spread systematically resulting in sepsis and major organ shut down leading to mortality.

A holistic assessment of the patients needs is essential to ensure the healing potential is optimized.

Advancis Medicals wound dressing portfolio is designed to manage wounds throughout the healing process. It includes dressings which address the most problematic aspects of wound management i.e. bacteria in wounds, removal of debris, manage exudate, reducing wound odors and maintaining a balanced moist wound healing environment. Also included in the advances range is a dressing for improving scars. See Products [link] to identify the most appropriate dressing regimen for the wound diagnosis. It may be necessary to use a primary wound dressing together with an absorbent secondary dressing depending on the assessment of the wound.

The management of chronic (non-progressing) wounds can be a complex matter requiring the advice or intervention of a specialist Nurse, Doctor or Consultant. The information contained in this section is only a guideline and there are many more aspects of wounds which have been omitted. If you have any concerns over a wound always seek the advice of a qualified medical practitioner.

Typical Wound Aetiologies

Leg Ulcers
These always occurs somewhere between the ankle and the mid-calf. They can be brought on by a trauma or erupt spontaneously. The underlying cause is a compromised supply of nutrition to the area due to either poor venous return or arterial problems. The treatment for these two conditions is entirely different. Venous leg ulcers account for about 90% of all leg ulcers and are treated with compression therapy. Dressing selection is dependent on whether infection is present or not. Arterial ulcers can only be rectified surgically and dressings are selected to manage the symptoms. If an arterial leg ulcer is incorrectly diagnosed and treated with compression therapy, the consequences can be very serious. There are ulcers of mixed aetiology with have to be treated cautiously, probably with reduced compression. It important that a clinician carries out a diagnosis and the Ankle Brachial Pressure Index (ABPI) is commonly used to diagnose the aetiology.

Decubitus Ulcers
Otherwise known as pressure sores, these ulcers are caused by the force exerted by bedding or seating on bony prominences. The pressure on the skin over bone can be sufficient to cause ischemia (tissue death) as the blood supply to the area is seriously compromised when the capillaries are compressed. These ulcers appear at first as red marks or very small ulcers but there is always serious underlying damage as the pressure is greatest nearest the bone. Muscle and fat are more susceptible to ischemia than skin. It is often the case that a surgical procedure is required to excise the area of damaged tissue which can be very large. Pressure ulcers will not heal unless the pressure is removed. The wound is then treated according to the diagnosis and any underlying issues.

Burns
Burns can be caused by thermal extremes, chemicals or radiation. They involve either superficial damage to the epidermis resulting in blisters or loss of tissue involving epidermis, dermis, and subcutaneous tissue and may involve muscle and bone. Superficial burns are most painful as the nerves remain functional, although they are the least serious and sunburn is a good example of a radiation burn. Burns often involve a large area of tissue loss and consequently a high risk of infection. Burns may require surgical grafts to replace the lost tissue. High exudate is common with deep burns and managing them can be very difficult. They are amongst the most distressing of wounds for patients as they may result in scaring or disfigurement. With the aid of modern dressings and compression therapy the outcome from serious burns can be greatly reduced.

Traumatic Wounds
These are the result of an impact injury with either a sharp or blunt object resulting in tissue damage. The margins of the wound are often jagged and difficult to proximate. Typically these are the result of accidents either in the home, workplace or on the road and occasionally result from an assault. The wound may only be an indication of more serious injuries to bone, muscle or vital organs. Surgery maybe necessary and superficial injuries are treated in A&E departments of hospitals or by the local GP surgery. The elderly are more susceptible to minor trauma injuries due o the friability of tissue with compromised nutritional supply caused by aging and long term life style factors. Superficial and sutured wounds should heal by primary intent but if bacteria are present and overwhelm the bodies natural defences the use of anti-bacterial dressings of systemic antibiotics may be indicated.

Surgical wounds
Wounds inflicted during surgical procedures are sutured, glued or stapled in order to bring the margins of the wound together and effect a speedy and cosmetically acceptable healing. They are nearly always neat incision although occasionally involve the removal of tissue making the wound larger. Very occasionally they may require grafting to replace loss of tissue. Nosocomial (hospital acquired) infection is unfortunately too common and many have exhaustive cleansing routines to help to try to reduce the incidence. The routine (or prophylactic) use of anti-bacterial dressings to protect wounds during periods of hospitalization is generally not accepted practice. This is due to possibilities of some therapies developing new resistant bacteria due to the overuse of the anti-bacterial agent. Many anti-bacterial dressings have numerous contra-indications and the screening and monitoring of patients would have to be increased. Also, cost cannot be ruled out as many anti-bacterial dressings are expensive. Using Activon anti-bacterial dressings from Advancis Medical can overcome most if not all of these issues.

Oncology
When cancerous cells invade the epithelium they can result in fungating ulcers. These wounds are particularly difficult to manage and are susceptible to bacterial colonization. The general health of the patient can be poor and they may be in an immune compromised state. The wounds can be odorous and +++highly exudating, wound management is mainly concerned with improving the patients quality of life. The care plan is commonly palliative not curative. The use of Activon dressings for odour control together with Eclypse dressings for wound management has demonstrated excellent QOL improvements. Another wound connected to oncology is tissue damage as a result of radiation therapy.

Wound Infection
Infection--a factor commonly related to delayed closure for many chronic and acute wounds--is associated with relatively high levels of bacteria in viable tissues. But bacteria also can delay wound healing at lower levels before tissue invasion via toxin secretion either directly from viable cells (exotoxins) or as a result of cell lysis (endotoxins). These toxins tend to cause local necrosis and disrupt the delicate balance of critical mediators such as cytokines and proteases necessary for healing progression. Therefore, toxin control or absorption is a potentially valuable adjunct to any infection control modality.

An "endotoxin" is a toxin, which unlike an "exotoxin", is not secreted in soluble form by live bacteria, but is a structural component in the bacteria which is released mainly when bacteria are lysed (die).

Worst wound infecting bacteria

1. Streptococcus
Pyogenes Streptococcus pyogenes produces a wide array of virulence factors and a very large number of diseases. Virulence factors of Group A streptococci include: (1) M protein, fibronectin-binding protein (Protein F) and lipoteichoic acid for adherence; (2) hyaluronic acid capsule as an immunological disguise and to inhibit phagocytosis; M-protein to inhibit phagocytosis (3) invasins such as streptokinase, streptodornase (DNase B), hyaluronidase, and streptolysins; (4) exotoxins, such as pyrogenic (erythrogenic) toxin which causes the rash of scarlet fever and invasive toxigenic infections can result in necrotizing fasciitis, myositis and systemic toxic shock syndrome.

2. Psuedomonas Aeruginosa
Pseudomonas aeruginosa is an opportunistic pathogen, meaning that it exploits some break in the host defenses to initiate an infection. It causes urinary tract infections, respiratory system infections, dermatitis, soft tissue infections, bacteremia, bone and joint infections, gastrointestinal infections and a variety of systemic infections, particularly in patients with severe burns and in cancer and AIDS patients who are immuno-suppressed. Pseudomonas aeruginosa is primarily a nosocomial infection, it is a serious problem in patients hospitalized with cancer, cystic fibrosis, and burns. The case fatality rate in these patients is 50 percent.

3. Staphylococcus Aureus
N.B. The enzyme coagulase, produced by a few of the Staphylococcus species, is a key feature of pathogenic Staph. The enzyme produces coagulation of blood, allowing the organism to "wall " its infection off from the host's protective mechanisms rather effectively. Staphylococcus aureus causes a variety of suppurative (pus-forming) infections and toxinoses in humans. It causes superficial skin lesions such as boils, styes and furunculosis; more serious infections such as pneumonia, mastitis, phlebitis, meningitis, and urinary tract infections; and deep-seated infections, such as osteomyelitis and endocarditis. S. aureus is a major cause of hospital acquired (nosocomial) infection of surgical wounds and infections associated with indwelling medical devices. S. aureus causes food poisoning by releasing enterotoxins into food, and toxic shock syndrome by release of superantigens into the blood stream.

S. aureus expresses many potential virulence factors: (1) surface proteins that promote colonization of host tissues; (2) invasins that promote bacterial spread in tissues (leukocidin, kinases, hyaluronidase); (3) surface factors that inhibit phagocytic engulfment (capsule, Protein A); (4) biochemical properties that enhance their survival in phagocytes (carotenoids, catalase production); (5) immunological disguises (Protein A, coagulase, clotting factor); and (6) membrane-damaging toxins that lyse eukaryotic cell membranes (hemolysins, leukotoxin, leukocidin; (7) exotoxins that damage host tissues or otherwise provoke symptoms of disease (SEA-G, TSST, ET (8) inherent and acquired resistance to antimicrobial agents.