DISCUSSION
Wound healing is affected by multiple factors categorized into systemic and local. Old age, female sex, stress, diabetes and obesity are related to delayed or impaired wound healing. Delayed wound healing in aged is related to altered inflammatory response such as delayed infiltration of T-cells at the wound and alteration in chemokines and macrophages recruitment (3). Every phase of the wound healing becomes delayed or modulated like platelet aggregation, macrophage recruitment, cytokines release, epithelialization, neovascularization and collagen synthesis, reduced collagen turnover and reduced wound strength. Stress caused by prolonged illness has also inverse impact on wound healing. Stress can lead to anxiety and depression which can result in unhealthy behavior and impaired sleep pattern. In addition, it also disturbs the endocrine system leading to hyperglycemic state because of increased nor-epinephrine, which itself can impair wound healing.
Local factors responsible for delayed or non-healing wound are poor soft tissue coverage, hypoxia and infection. Because of the deep and large wound, vascularity of the area is reduced and oxygen tension decreases. It causes reduced cytokines production and macrophages recruitment. This patient had all of these condition which were cocktail for impaired wound healing. In addition, the wound was grossly infected. Bacteria and endotoxins can lead to prolonged elevation of pro-inflammatory cytokines such as IL-1 and TNF-alpha and elongate inflammatory process and if this continues, the wound may enter into chronic state.
So the appropriate planning is necessary to treat these wounds. Intravenous antibiotics along with repeated debridement is necessary to reduce the microbial load. Sometimes radicle debridement can lead to loss of large amount of soft tissue, hence Negative pressure wound therapy (NPWT) is needed to suck the infection out and reduce the swelling to enhance micro vascularity. NPWT has also been found to be helpful in enhancing the formation of healthy granulation tissue and wound contraction, hence reducing the exposed surface area (4,5).
The role of placental extract gel is to stimulate the formation of granulation, which was quite helpful in this particular case as the foot has almost nil subcutaneous tissue (6). Daily change of dressing should be done to prevent the contamination by microbes and dirt. In addition to these, it is must to add extra-amount of protein in the diet, adequate amount of hydration should be maintained. Proper counselling and assurance is necessary to relieve the stress related to the wound.
The amputation should be kept as reserve even at old age as it causes psychological trauma to the patient. Even the large wound can heal with time and correct decision so efforts must be done to let it heal naturally. Choosing a flap in old age is little doubtful, as vascularity of the flap is naturally reduced because of the age.
Because of these adverse factors of the wound healing, there remain a possibility of chronic non-healing wound and impending amputation. It needs multimodality to treat a wound like this. With combined effort from surgeon, physician, nutritionist, psychologist and time, these wounds can be treated and limb salvage can be possible even without a major surgery and without increasing morbidity.