Eighteen full-thickness
burns models of Japanese white rabbits were established. They were randomly divided into 3 groups of traditional
dressing, biological dressing and
negative pressure wound therapy (NPWT) (n=6 each), according to the random number table. Eschar excision was performed three days later. The
wound bed was observed and
wound tissue was harvested for counting the quantity of bacteria, tissue dry wet ratio, measuring the level of
tumor necrosis factor alpha (TNF-α),
interleukin (IL)-1β and
IL-6, the amount of
collagen fibers and the microvessel density instantly and again seven days later. Statistical analyses were performed.
RESULTS: The NPWT group was better than other groups by observing the
wound bed. The quantity of bacteria of traditional dressing group,
biological dressing group and NPWT group at the time point of seven days after escharectomy turned out to be (9.4±1.5)×10(4,) (8.1±2.7)×10(4,) (3.9±0.7)×10(4) cfu/g, the NPWT group was significantly lower than traditional dressing group and
biological dressing group (both P<0.05), and all lower than that at the time point of the day when escharectomy was performed (576.9±169.5)×10(4,) (589.9±99.6)×10(4,) (583.0±160.4)×10(4) cfu/g ( all P<0.05). There were no statistically significant differences among three groups at two time points in tissue dry wet ratio (all P>0.05). The
IL-6 of
biological dressing group was higher than that of traditional dressing group at the time point of seven days after the eschar excision was performed[(94±10) vs (76±8) ng/L, P<0.05]. The amount of
collagen fibers of three group at the time point of seven days after escharectomy turned out to be (60±9), (55±12), (77±17). The NPWT group was significantly higher than traditional dressing group and
biological dressing group (P<0.05), and all higher than that at the time point of the day when escharectomy was performed[(39±6), (39±11), (38±6)](all P<0.05). The microvessel density of three groups at the time point of seven days after escharectomy turned out to be (42±6), (53±4), (82±10). The NPWT group was higher than that of the other two groups, and
biological dressing group was higher than that of traditional dressing group (all P<0.05). The
biological dressing group and NPWT group were both higher than that of the day when the eschar excision was performed (36±5) and (36±5) (P<0.05).
CONCLUSIONS: NPWT is the optimal selection for
wound to inhibit the growth of bacteria, promote the accumulation of
collagen and tissue vascularization. But these managements have similar effects on reducing tissue
edema and inflammatory reaction.