Infection Management

Wounds typically heal in four sequential but overlapping phases — hemostasis, inflammatory, proliferative and remodeling — ultimately leading to tissue regeneration. Healing sometimes stalls for various reasons, a key one being extensive inflammation, which disrupts the normal cascade of healing and leads to chronic and hard-to-heal wounds. A vicious cycle of ongoing inflammation, pain and poor quality of life often follows. Understanding how to break this cycle is essential for wound care clinicians who want to optimize healing outcomes and patient quality of life.

Wound healing can stall for a number of reasons. Wounds that have not healed or significantly reduced in size after four to six weeks are considered chronic. They are characterized by a multitude of impeding factors including biofilm, excess matrix metalloproteinases (MMPs) and extracellular matrix degradation, inflammation, fibrosis, unresponsive keratinocytes and fibroblasts, and atypical growth factor signaling.

Biofilm: Colonies of multiphenotype, free-floating bacteria that secrete a polysaccharide matrix that protects the bacteria from immune response and antibiotics.

Chronic wounds: Wounds that stall in the inflammation phase and fail to progress toward healing within 3 months are considered chronic or hard to heal.

Continuous inflammation: When wound healing becomes stalled in the inflammatory phase because of the presence of bacteria and their endotoxins, the wound is unable to move out of the inflammatory phase and into the repair phase.

As scientists and researchers have delved deeper into the causes of wounds and wound chronicity, matrix metalloproteinases, or MMPs, have come into sharper focus. MMPs are not just present in chronic wounds — they also play an essential role in acute wounds.

An injury to the human body initiates a wound healing chain reaction that occurs in four sequential but overlapping phases: hemostasis, inflammatory, proliferative and maturation. This post focuses on the second (inflammatory) phase, which begins after blood flow stops (i.e., hemostasis) and defender white blood cells, or leukocytes, migrate to the site of the injury — a process known as chemotaxis.

Anoxia: A condition marked by the absence of oxygen reaching the tissues. It differs from hypoxia, in which there is a decrease in the oxygen levels to tissue.

Biocide tolerance: Demonstrating a tolerance to substances that destroy living things, such as bacteria. The initial stage in the life of biofilm can become biocide tolerant within 12 hours.

Calcium alginate: A water-insoluble, gelatinous substance that is highly absorbent. Dressings with calcium alginate can help to maintain a moist healing environment.

Moisture-associated skin damage (MASD) is a common problem for wound clinicians. It connotes a spectrum of skin damage caused by inflammation and erosion (or denudation) of the epidermis resulting from prolonged exposure to various sources of moisture and potential irritants. These can include urine, stool, perspiration, wound exudates, or ostomy effluent. MASD includes several different categories: incontinence-associated dermatitis (AID), intertriginous dermatitis, periwound skin damage, and peristomal MASD. Of these categories, IAD is one of the more challenging issues for clinicians to recognize and treat. It is not uncommon for IAD to be inaccurately assessed as a stage 2 pressure injury. For the purposes of this blog, the focus is on differentiating between IAD and pressure injuries. Treatment strategies are also addressed.

By Cathy Wogamon, DNP, MSN, FNP-BC, CWON, CFCN

A pilonidal cyst is a pocket located at the top of the cleft of the buttocks that usually results from an embedded or stiff hair. This area may remain dormant for years and cause no major issues; however, often the embedded or stiff hair may cause the cyst to become inflamed and infected, resulting in an abscess that requires an incision to drain the infected material. These abscesses can recur, causing the patient to require surgical intervention to remove the cyst. After surgery, some patients tend not to heal well, and the result is a chronic, tracking wound in an area that is difficult to heal.

Prevention and management of biofilm and infection in wounds can be supported by using antimicrobial and antibiofilm dressings. Internationally, there has been a rising prevalence of antibiotic-resistant organisms; this has resulted in increased incorporation of antimicrobial dressings in wound management. These dressings offer many advantages because they are easy to use, are readily available, have a decreased risk of resistance, and deliver sustained release of antimicrobial agents to the wound bed. This mode of action allows for a lower concentration of the agent and thereby lowers the possibility of toxicity to host cells.

Bioburden: Bioburden is the number of microorganisms in a wound, and a high bioburden can cause delayed wound healing.

Biofilm: Biofilms are usually composed of mixed strains of bacteria, fungi, yeasts, algae, microbes, and other cellular debris that adhere to the wound surface.

Epibole: Epibole refers to rolled or curled-under closed wound edges. These rolled edges are thickened epidermis that may be callused, dry, scaly, and/or hyperkeratotic. When epibole is present in a wound, it signals to the body that the wound has healed, even though the wound remains open. Epibole must be resolved to allow the wound to close.