Review of Burn Research for Year 2014

A Scoping Review on the Long-Term Outcomes in Persons with Adult-Acquired Burn Injuries

Adult-acquired burn injuries are a life-altering event that can lead to debilitating functional or psychological impairments. With advancements in health care resulting in decreased mortality rates, survivors of burn injuries can expect to live longer. This warrants a shift in focus to better understand what happens to adults once they are discharged from the hospital into the community. Therefore, the purpose of this scoping review was to map the literature regarding the long-term outcomes of community-dwelling adult-acquired burn survivors. A computer-assisted literature search was conducted on literature from January 1, 2000 to August 31, 2018 utilizing four large databases (MEDLINE, EMBASE, CINHAL, and PsycINFO). Articles were included if they had a minimum of five individuals with a burn injury as a result of an accidental injury who were at least 18 years of age at the time of injury. Fifty-four articles were found suitable for inclusion in this review. The majority of studies were conducted in the United States and were longitudinal in design. Four themes were apparent from the articles: postburn complications, psychosocial outcomes, quality of life, and community participation. Data are lacking with respect to outcomes more than 5 years postburn as well as qualitative research. Furthermore, more literature is needed to understand the impact of postburn complications, coping strategies, and posttraumatic growth as well as barriers to community participation. Overall, there is an emerging body of literature that describes the long-term outcomes of adult-acquired burn survivors up to 5 years postburn.

Cardiovascular Responsiveness to Vasopressin and α1-Adrenergic Receptor Agonists After Burn Injury

The effects of burn injury on cardiovascular responsiveness to vasoactive agents are not well understood. The aims of this study were to determine whether burn injury alters cardiovascular reactivity to vasoactive drugs in vivo and intrinsic function of isolated mesenteric resistance arteries. Anesthetized Sprague-Dawley rats were subjected to sham procedure or 30% TBSA dorsal scald burn, followed by crystalloid resuscitation (Parkland Formula). At 24, 72, 96, and 168 hours post burn, rats were reanesthetized, and the mean arterial blood pressure (MAP) responses to various doses of the α1-adrenergic receptor agonist phenylephrine and arginine vasopressin were tested. Mesenteric arteries were harvested from uninjured animals and at 24 and 168 hours post burn. The responsiveness of arteries to phenylephrine and arginine vasopressin was tested by pressure myography. Dose response curves were generated and EC50 concentrations, Hill slopes, and maximal effects were compared. The potency of phenylephrine to increase MAP was reduced 2-fold 24 hours post burn (P < .05 vs sham) and gradually normalized at later time points. The reactivity of isolated arteries to phenylephrine was not significantly altered after burns. The potency of arginine vasopressin to increase MAP and to constrict isolated arteries was increased 2- to 3-fold at 24 hours post burn (P < .05) and normalized at later time points. Our findings suggest that burn injury differentially regulates vasopressor and blood pressure effects of α-adrenergic and vasopressin receptor agonists. Intrinsic vasopressin receptor reactivity of resistance arteries is sensitized early after burns. These findings will help to optimize resuscitation strategies and vasopressor use in difficult to resuscitate burn patients.

TLR2 affects CD86 expression and inflammatory response in burn injury mice through regulation of p38

The aim of this study was to assess the effects of TLR2-p38-CD86 signaling pathways on the inflammatory response in a mouse model of burn injury. Wild-type (TLR2^+/+) and mutant-type (TLR2^-/-) mice were obtained, and a mouse burn injury model was constructed. Tissue samples were examined with hematoxylin and eosin staining and the transferase mediated nick end labeling (TUNEL) method. Macrophages were treated with TLR2 agonist and p38 inhibitor. The expression levels of TLR2, p38, CD86, IL-1β, and TNF-α were quantified by RT-qPCR, Western blot, and ELISA. When compared with the sham group, the burn group had a significantly higher rate of apoptosis as well as higher expressions of TLR2, p38, CD86, IL-1β, and TNF-α. Inhibiting TLR2 was shown to significantly reduce the expressions of p-p38, CD86, IL-1β, and TNF-α. In the results of in-vitro experiments, TLR2 agonist increased the expression of p-p38, CD86, IL-1β, and TNF-α, whereas a p38 inhibitor was shown to reduce the expression of CD86, IL-1β, and TNF-α. Our results suggest that the TLR2-p38-CD86 signaling pathway plays a vital role in inflammation associated with burn injury.