Objective To compare the air permeability,water absorption and water locking properties of two different foam dressings,thus to provide theoretical and experimental evidence to alternative optimization for acute and chronic wound.Methods Five Mepilex foam dressings(group 1) and PermaFoam Comfort dressings(group 2) each was selected.Simulated wound exudation was made by NaCl and CaCl·H2O.The water-absorbing rate of dressings at post immersion 24 h (PIH),the water-absorbing speed of dressings at post immersion 1,5,10,20 min,the diffusion diameter of exudation dripped on the surface of dressings for 5 min,the beaker filled with exudation was sealed tightly by dressing for 24 h,and the weight was gotten before and after 24 h.Statistical analysis was performed.Results (1) The water-absorbing rate:the group 1(616±19)% was significantly higher than (313±13)% of the group 2 (t=29.137,P<0.01);(2) The water-absorbing speed:the group 1 (119.68±2.59)g·s-1·m-2,(24.39±0.62)g·s-1·m-2,(12.33±0.29)g·s-1·m-2,(12.33±0.29)g·s-1·m-2 were significantly higher than those of the group 2[(65.85±4.37)g·s-1·m-2,(13.82±1.03)g·s-1·m-2,(7.16±0.41)g·s-1·m-2,(3.66±0.12)g·s-1·m-2,t=23.704,t=19.708,22.947,31.764,all P<0.01];(3) The water holding capacity:the group 1 (5.66±0.15)cm was significantly higher than (2.2±0.12)cm of the group 2,(t=39.089,P<0.01);(4) The air permeability:there was no statistically significant difference between the two groups(t=0.189,P>0.05).Conclusion The Mepilex foam dressing is more suitable for the early stage of acute wound with large exudation in short time,while the PermaFoam Comfort dressings is better for chronic wound or the later period of acute with less exudation in a relative slow seepage velocity.

Objective: To explore the influence of different inner dressings in negative-pressure wound therapy (NPWT) on escharectomy wound of full-thickness burn rabbits. Methods: Eighteen Japanese white rabbits were inflicted with full-thickness burn on unilateral back. They were divided into polymer dressing group (PD), biological dressing group (BD), and silver biological dressing group (SBD), according to the random number table, with 6 rabbits in each group. On 3 days post burn, the wounds were performed with escharectomy, and then wounds of rabbits in group PD were covered with polyurethane foam. Wounds of rabbits in group BD were covered with porcine acellular dermal matrix (ADM) and wounds of rabbits in group SBD were covered with silver porcine ADM. Then continuous NPWT was performed on rabbits of the three groups for 7 days. Immediately after surgery and on post surgery day (PSD) 7, general observation of wound was conducted and tissue around the wound was harvested for determination of dry to wet weight ratio. The content of bacteria was counted and the content of tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), and IL-6 in wound was determined by enzyme-linked immunosorbent assay. Fibroblasts in wound were counted after Masson staining and number of microvessels was counted after CD31 antibody immunohistochemical staining. Data were processed with analysis of variance for repeated measurement, LSD-t test, paired samples t test, and Bonferroni correction. Results: (1) Immediately after surgery, there was no granulation tissue in basal wound of rabbits in the three groups, with rich blood supply and obvious edema. On PSD 7, much granulation tissue was found in basal wound of rabbits in the three groups, with no or mild edema and no obvious redness and swelling in wound edge. (2) There were no significant differences in dry to wet weight ratios of tissue around the wound among and within the three groups immediately after surgery and on PSD 7 (with F values respectively 0.70 and 0.09, t values from 0.17 to 0.52, P values above 0.05). (3) Immediately after surgery, the content of bacteria in wounds of rabbits in groups PD, BD, and SBD was respectively (603.0±146.0) ×10^4, (573.0±63.0) ×10^4, and (590.0±100.0)×10⁴ colony-forming unit (CFU)/g, with no significant difference among them (F=0.13, P>0.05). On PSD 7, the content of bacteria in wounds of rabbits in groups PD, BD, and SBD were respectively (5.4±0.8) ×10^4, (4.6±0.9) ×10^4, and (3.5±0.9)×10⁴ CFU/g. Among them, the content of bacteria in wounds of rabbits in group SBD was lower than that in groups PD and BD, respectively (with t values respectively 3.78 and 2.29, P<0.05 or P<0.01). The content of bacteria in wounds of rabbits in the three groups on PSD 7 was decreased compared with that immediately after surgery (with t values from 10.05 to 21.81, P values below 0.01). (4) There was no significant difference in content of TNF-α, IL-1β, and IL-6 in wounds of rabbits in the three groups immediately after surgery and on PSD 7 (with F values from 0.10 to 1.89, P values above 0.05). The content of TNF-α in wounds of rabbits in the three groups on PSD 7 was significantly higher than that immediately after surgery (with t values from 2.93 to 5.01, P<0.05 or P<0.01). (5) There was no significant difference in amount of fibroblasts in wounds of rabbits in the three groups immediately after surgery and on PSD 7 (with F values respectively 0.01 and 0.81, P values above 0.05). The amount of fibroblasts in wounds of rabbits in the three groups on PSD 7 was larger than that immediately after surgery (with t values from 4.78 to 11.58, P values below 0.01). (6) There was no significant difference in number of microvessels in wounds of rabbits in the three groups immediately after surgery and on PSD 7 (with F values respectively 2.42 and 2.49, P values above 0.05). The number of microvessels in wounds of rabbits in the three groups on PSD 7 was larger than that immediately after surgery (with t values from 7.17 to 11.14, P values below 0.01). Conclusions SBD is better at inhibiting the growth of bacteria. PD, BD, and SBD have almost the same effects on reducing tissue edema and inflammatory reaction, and on promoting the accumulation of collagen fibers and tissue vascularization.

Objective To explore the effects of different fluid resuscitation program on renal function in swine during shock stage of severe burn.Methods Twenty-four Guangxi Bama miniature swine were inflicted with 40％ total body surface area on the back,and then they were divided into four groups according to the random number table,with 6 swine in each group.At post injury hour (PIH) 2,swine in succinylated gelatin group (S),hydroxyethyl starch group (H),and allogeneic plasma group (A) were respectively resuscitated with succinylated gelatin,hydroxyethyl starch 130/0.4,and plasma according to burn shock “ domestic general” resuscitation formula,and swine in Parkland group (P) were resuscitated with lactated Ringer's solution according to Parkland formula.Hemodynamic indexes including heart rate,blood pressure,urine volume,pulmonary capillary wedge pressure,and central venous pressure before injury,at the first and second PIH 24 were recorded.The volume of resuscitation fluid was calculated at the first and second PIH 24.Blood and urine samples were collected before injury and at PIH 4,8,24,and 48,and then serum creatinine and urea nitrogen were detected by automatic biochemical analyzer,urine microalbumin and urine creatinine were detected by automated urine analyzer and the ratio of which was calculated.The renal tissue of swine in each group was obtained at PIH 48,and the pathologic changes were observed by optical microscopy and electron microscope.Data were processed with analysis of variance of repeated measurement,one-way analysis of variance,and LSD test.Results (1) The hemodynamic indexes of swine in each group were similar before injury and at the first and second PIH 24 (with P values above 0.05).Compared with those before injury,except that the heart rate of swine in group A had no significant change at the first PIH 24 (P ＞ 0.05),the heart rate of swine in each group was significantly increased at the first and second PIH 24 (with P values below 0.01);except that the systolic blood pressure of swine in group P was significantly increased at the first and second PIH 24 (P ＜0.05 orP ＜0.01),there were no significant changes of systolic blood pressure and diastolic blood pressure of swine in each group at the first and second PIH 24 (with P values above 0.05);except that urine volume of swine in groups S and A was significantly decreased at the first PIH 24 (P ＜ 0.05 or P ＜ 0.01),there were no significant change of urine volume of swine in each group at the first and second PIH 24 (with P values above 0.05);pulmonary capillary wedge pressure and central venous pressure of swine in each group were significantly increased at the first and second PIH 24 (P ＜ 0.05 or P ＜ 0.01).(2) Compared with that in group A,the volume of resuscitation fluid of swine in groups S and H had no significant change in the first and second PIH 24 (with P values above 0.05),while it was significantly increased in group P in the first PIH 24 and significantly decreased in the second PIH 24 (with P values below 0.05).(3) Compared with those in group A,except that serum creatinine of swine in group H was significantly increased at PIH 24 and significantly increased in group P at PIH 4,8,24,and 48,urea nitrogen of swine in group P was significantly decreased at PIH 4 and 8 and significantly increased at PIH 48,the ratio of urine microalbumin to urine creatinine of swine in group P was significantly increased at PIH 8,24,and 48 (P ＜ 0.05 or P ＜ 0.01),serum creatinine,urea nitrogen,and the ratio of urine microalbumin to urine creatinine of swine in each group had no significant change at each time point (with P values above 0.05).Serum creatinine of swine in group P was (125 ± 16) μmol/L at PIH 24,which was significantly higher than that before injury [(75 ± 13) μmol/L,P ＜ 0.05].Urea nitrogen of swine in group S was (2.90 ± 1.17) μmol/L at PIH 48,which was significantly lower than that before injury [(4.60 ±0.47) μmol/L,P ＜0.05];urea nitrogen of swine in group H was (4.82 ±0.82)μmol/L at PIH 4,which was significantly higher than that before injury [(3.80 ± 0.73) μmol/L,P ＜ 0.05];urea nitrogen values of swine in group A were respectively (4.80 ± 0.33),(4.92 ± 0.35),and (2.60 ± 0.27) μmol/L at PIH 4,8,and 48,while those at PIH 4,8 were significantly higher and at PIH 48 was significantly lower than the value before injury [(3.93 ± 0.32) μmol/L,with P values below 0.01].The ratios of urine microalbumin to urine creatinine of swine in group P were respectively (106.7 ±16.4) and (171.6 ± 36.9) mg/mmol at PIH 24 and 48,which were significantly higher than the ratio before injury [(59.0 ± 3.0) mg/mmol,with P values below 0.01].The serum creatinine,urea nitrogen,and the ratio of urine microalbumin to urine creatinine of swine in each group at the other time points were similar to those before injury (with P values above 0.05).(4) The renal tissue of swine in the four groups had no obvious pathological change.Conclusions According to the renal function results,fluid resuscitation with electrolyte and colloids are better than with lactated Ringer's solution in swine during shock stage of burn injury,while natural colloids and succinylated gelatin have similar effects,and both are superior to hydroxyethyl starch 130/0.4.

One 24 years old female patient who suffered extremely severe burn in the third trimester of pregnancy was admitted to the Department of Burns and Skin Repair Surgery of the Third Affiliated Hospital of Wenzhou Medical University on 9th May, 2015. Intrauterine distress occurred after injury and stillbirth was confirmed within 12 hours. In cooperation with the obstetrician, the labor was induced on post injury day (PID) 5. Septic shock and multiple organ dysfunction syndrome occurred on PID 8. Through treatments including anti-infection, ventilator-assisted ventilation, cardiotonic diuresis, and escharectomy and skin grafting, the patient was finally cured. This case indicates that it is crucial to grasp the right time and choose a reasonable induction of labor to deal with stillbirth. The scheme of transvaginal induction of labor after shock is a worthy question to explore. The main characteristics of this patient include the extreme paroxysmal changes in breath, circulation, and urine volume within 24 hours after induced labor, which should be monitored dynamically for effective and timely adjustment of respiratory circulation support. This may be another key point for the rescue of this type of patient. To seize the opportunities to perform escharectomy, cover the wound with xenogenic skin graft, and perform skin grafting in time for wound repair remain the top priority.