Inflammation is vital to successful burn wound healing, and inflammatory mediators (cytokines, koninis, lipids, and so forth) provide immune signals to recruit leukocytes and macrophages that initiate the proliferative phase . Wound re-epithelialization, or closure, in the proliferative phase via keratinocyte and fibroblast activation, or migration from dedifferentiated hair follicles and other epidermal analogs, is mediated by cytokines recruited in the inflammatory phase. While this indicates that inflammation is essential for wound healing, aberrant inflammatory pathways have also been linked to hypertrophic scarring, and anti-inflammatory treatments could potentially aggravate symptoms and delay wound healing.
Significant edema that is initiated by several factors including vasodilatations, extra vascular osmotic activity, and increased micro vascular permeability often accompanies inflammation. Excessive or prolonged edema and inflammation exacerbate pain and impair wound healing. Interestingly, studies suggest that in the absence of infection, inflammation might not be required for tissue repai.Since inflammation can have both beneficial and detrimental effects on burn wound healing; the clinical challenge becomes management, applying therapeutic intervention only when inflammation and edema become excessive.
Treatment of inflammation in large burns is difficult, as recently discussed in detail elsewhere. Traditional anti-inflammatory treatments that focus on the inhibition of prostaglandin synthesis, such as no steroidal anti-inflammatory drugs or glucocorticoids, impair wound healing . However, steroid administration has been shown to reduce inflammation, pain, and length of hospital stay in burn patients in several small studies . Early excision and grafting has become the gold standard for treatment of full and deep partial thickness burns , in part because early excision helps reduce the risk of infection and scarring. The timing of debridement coincides with the inflammatory phase of healing, as the burn Escher removed during excision is an inflammatory nisus and a rich pabulum for bacterial proliferation.
Nontraditional anti-inflammatory treatments, such as opioids, have gained considerable attention but have yet to translate promising preclinical results into clinical practice for wound healing. While the majority of animal studies have demonstrated consistent anti-inflammatory effects of opioids on peripheral neurons, clinical studies have shown little to no effect on inflammation. Furthermore, topical morphine delayed the early inflammatory phase and accelerated the later proliferative phase, which is supported by in vitro studies showing opioid stimulation of keratinocyte migration. Large-scale clinical trials evaluating opioid efficacy on wound healing have not yet been conducted.