Influence of high-voltage electric burn on the microcirculation of heart in rabbit / 中华烧伤杂志

<p><b>OBJECTIVE</b>To study the influence of high-voltage electric burn on the microcirculation of heart in rabbit.</p><p><b>METHODS</b>One-hundred and twenty New Zealand rabbits of clean grade were divided into control group (C) and electric burn group (EB) according to the random number table, with 60 rabbits in each group. Rabbits in EB group were subjected to high-voltage electric burn (the electrical current flow into the left foreleg at the lateral side of proximal end and out from the corresponding site of the right hind leg) with voltage regulator and experimental transformer. Rabbits in C group were sham injured with the same devices without electrification. At 15 minutes before injury, and 5 minutes, 1, 2, 4, 8 hour (s) post injury (PIM or PIH), ten rabbits in each group were chosen to examine the cardiac apex microcirculation hemoperfusion (CAMH) with laser Doppler hemoperfusion image instrument. The morphologic changes of microvessels of left ventricular wall tissues of 2 rabbits from each of the 10 rabbits collected at above-mentioned time points were observed with light microscope and transmission electron microscope. Auricular vein blood of rabbit was harvested at above-mentioned time points for the determination of aspartate amino transferase (AST), lactate dehydrogenase (LDH), hydroxybutyrate dehydrogenase (HBDH), creatine kinase (CK), and creatine kinase isozyme MB (CK-MB) by full-automatic biochemical analyzer. Data were processed with two-factor analysis of variance and LSD test.</p><p><b>RESULTS</b>(1) The differences between C group and EB group in detection results were statistically significant, with F values from 425.991 to 3046.834, P values all below 0.01. Only the data within EB group were comparable. (2) At PIM 5, the CAMH value of rabbits in EB group was (1.96 ± 0.09) V, which was lower than that at 15 minutes before injury [(4.34 ± 0.35) V, P < 0.01]. The CAMH value of rabbits in EB group was increased at PIH 1 [(3.43 ± 0.30) V], and then it showed a tendency of decrease. (3) Bleeding and microthrombus formation were observed in venule and capillary vessel of rabbits in EB group at PIH 8. Breakage of basement membrane of capillary endothelial cells, mitochondrial swelling, and severe degranulation from damaged endoplasmic reticulum were observed in rabbits of EB group at PIH 8. (4) Levels of AST, LDH, HBDH, CK, and CK-MB in rabbits of EB group were significantly higher at PIH 1, 2, 4, 8 than at 15 minutes before injury (with P values all below 0.01). The AST level peaked at PIH 2 [(164 ± 39) U/L]. Levels of LDH and HBDH peaked at PIH 4, which were respectively (1016 ± 246) U/L and (487 ± 54) U/L. The CK level peaked at PIH 8 [(7799 ± 738) U/L]. The CK-MB level peaked at PIH 2 [(1848 ± 65) U/L].</p><p><b>CONCLUSIONS</b>High-voltage electric burn can bring damage to the microvessels of heart in rabbits and change blood flow of microcirculation, which should be given adequate attention during the treatment.</p>

Clinical effect of the concentrated suture fixation method on skin transplantation in the jaw and neck region / 中华烧伤杂志

<p><b>OBJECTIVE</b>To observe the clinical effect of the concentrated suture fixation method on skin transplantation on deep burn wound or wound of cicatricial deformity after burn in the jaw and neck region.</p><p><b>METHODS</b>One hundred and fourteen patients, hospitalized from April 2002 to December 2011, with deep burn or cicatricial deformity after burn in the jaw and neck region, were divided into packaging group and concentrated suture group according to the random number table. Each group had 57 patients including 48 cases with deep burn and 9 cases with cicatricial deformity. Traditional suture-package fixation method and concentrated suture fixation method were respectively used in packaging group and concentrated suture group to fix the autologous medium split-thickness skin in transplantation on wounds or scars. On post operation day (POD) 14, the skin microcirculatory perfusion flow of skin graft was measured, and the occurrence of ecchymoma, infection, and necrosis of skin in operative region were observed. The elasticity and contracture of grafted skin and scar hyperplasia on wound edge were observed 6 months after operation. Measurement data were processed with u test, while enumeration data with Fisher's exact test or Chi-square test.</p><p><b>RESULTS</b>(1) On POD 14, the skin microcirculatory perfusion flow in concentrated suture group [(2.86 +/- 0.8) V] was significantly higher than that in packaging group [(2.33 +/- 0.15) V, u = 17.776, P < 0.05]. (2) Ecchymoma occurred in 4 patients of packaging group and 3 patients of concentrated suture group, but the difference between two groups was not statistically significant (chi 2 = 0.152, P > 0.05). (3) Infection in operative region was observed in 1 patient of packaging group, while no patient in concentrated suture group showed this symptom. The difference between two groups was not statistically significant (P > 0.05). (4) Grafted skin in 6 patients of packaging group showed foliated necrosis, which was not observed on those of patients in concentrated suture group. The difference between two groups was statistically significant (P < 0.05). (5) Centipede leg-like scar hyperplasia on wound edge occurred in 21 patients in packaging group and 6 patients in concentrated suture group, and the difference between two groups was statistically significant (chi 2 = 10.920, P < 0.05). (6) Poor elasticity of grafted skin was detected in 17 patients of packaging group and 4 patients of concentrated suture group, and the difference between two groups was statistically significant (chi 2 = 9.865, P < 0.05). (7) Obvious contracture of grafted skin was observed in 15 patients of packaging group and 4 patients of concentrated suture group, and the difference between two groups was statistically significant (chi 2 = 11.684, P < 0.05).</p><p><b>CONCLUSIONS</b>Concentrated suture fixation method is suitable for application in transplantation of big sheet skin on wound in the jaw and neck region. It has high survival rate and is convenient for postoperative observation.</p>

Influence of high-voltage electrical burn on the rheological property of platelet and leukocyte in rats and the interventional effect of pentoxifylline / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the influence of high-voltage electrical burn (HEB) on the aggregation and adhesion of platelet and leukocyte in rats and the interventional effect of pentoxifylline (PTX).</p><p><b>METHODS</b>One hundred and eighty SD rats were divided into control, electrical burn (EB), and pentoxifylline treatment (PT) groups according to the random number table, with 60 rats in each group. (1) Ten rats were taken from each group at 15 minutes before injury for the observation of the microcirculatory perfusion of chest skin with Laser Doppler Perfusion Imager (LDPI), and the number of leukocyte adherent to mesenteric venule with Bradford Variable Projection Microscope (BVPM). Serum was collected from heart blood to determine the contents of platelet activating factor (PAF), thromboxane B2 (TXB2), prostacyclin (PGI2), P-selectin, E-selectin and L-selectin by double-antibody sandwich enzyme-linked immunosorbent assay. The ratio of TXB2 to PGI2 was calculated therefrom. (2) Model of HEB was reproduced in the remaining 50 rats of EB group and that of PT group with voltage regulator and experimental transformer (the electrical current applied to the left forelimb and exited from the right hind limb). The remaining 50 rats of control group were sham injured with the same devices without electric current. Within 2 minutes post injury (PIM), rats in control group and EB group were intraperitoneally injected with 2 mL isotonic saline, while rats in PT group were intraperitoneally injected with 2 mL pentoxifylline (50 mg/mL). At PIM 5 and 1, 2, 4, 8 hour(s) post injury (PIH), 10 rats of every group were randomly chosen at each time point for the observation of the microcirculatory perfusion of chest skin and the number of leukocytes adherent to mesenteric venule through the same method as used above, and the levels of the related factors of aggregation and adhesion of platelets and leukocytes were determined, and then the relative ratio was calculated. Data were processed with the analysis of variance of factorial design and LSD test.</p><p><b>RESULTS</b>The contents of PAF, TXB2, PGI2, P-selectin, E-selectin, L-selectin, and the ratio of TXB2 to PGI2, as well as the number of adhered leukocyte in EB group were higher, while the microcirculatory perfusion value was lower than those of control group, with F values from 854.20 to 8156.52, P values all below 0.01. The microcirculatory perfusion value and PGI2 content of PT group were higher, while the contents or number of other indexes were lower than those of EB group, with F values from 33.18 to 1033.99, P values all below 0.01. Only the data within EB group and PT group were comparable. The contents of PAF, TXB2, PGI2, P-selectin, E-selectin, L-selectin, and the ratio of TXB2 to PGI2, as well as the number of adhered leukocyte in EB group and PT group at each time point were significantly higher than those at 15 minutes before injury, while the microcirculation perfusion value was significantly lower than that at 15 minutes before injury (P values all below 0.001), with the exception of the ratio of TXB2 to PGI2 in PT group and E-selectin in EB group and PT group at PIM 5. The contents of PAF, TXB2, and E-selectin and the ratio of TXB2 to PGI2 in EB group peaked at PIH 4, and they were respectively (9.3 ± 0.9) ng/mL, (14.31 ± 0.65) nmol/mL, (271.2 ± 18.4) ng/mL and 4.62 ± 0.26. The contents of PGI2 and P-selectin, and the number of adhered leukocyte in EB group peaked at PIH 8, and they were respectively (3.98 ± 0.24) nmol/mL, (514 ± 24) ng/mL, and (25.50 ± 4.14) per 100 µm venule. The content of L-selectin peaked at PIH 2 [(876 ± 54) ng/mL]. The microcirculatory perfusion value was lowest at PIM 5 [(1.17 ± 0.10) V].</p><p><b>CONCLUSIONS</b>HEB can increase the contents of PAF, TXB2, PGI2, P-selectin, E-selectin, L-selectin, the ratio of TXB2 to PGI2, and the number of adhered leukocyte, as well as decrease the skin microcirculatory perfusion value. PTX can inhibit the aggregation and adhesion of platelets and leukocytes through increasing the content of PGI2 and decreasing contents of other factors mentioned above, thus alleviating the microcirculatory dysfunction after HEB.</p>

Rheological changes of leukocytes in mesentery capillary of rats with transcranial high-voltage electrical burn and the therapeutic effects of ulinastatin / 中华烧伤杂志

<p><b>OBJECTIVE</b>To study the influence of transcranial high-voltage electrical burn (HEB) on rheological changes of leukocytes in mesentery capillary in rats and the therapeutic effects of ulinastatin.</p><p><b>METHODS</b>Forty-five SD rats were divided into control (C), electrical burns (EB), and ulinastatin treatment (UT) groups according to the random number table, with 15 rats in each group. Model of HEB was reproduced in rats of EB and UT groups with voltage regulator and experimental transformer, and then rats in EB group was intraperitoneally injected with 2 mL isotonic saline while rats in UT group was intraperitoneally injected with 2 mL ulinastatin (2 x 10(4) U/kg). Rats in C group received sham burn with the same treatment as used in EB group but without electric current. Rheological changes of leukocytes in mesentery capillary were observed with Bradford microscope at 15 minutes before HEB and 5 minutes, 1, 2, 4, 8 hour (s) after HEB (PHM or PHH), including counting the number of rolling leukocytes, leukocytes rolling speed, the number of leukocytes adherent to mesentery capillary, total leukocyte-endothelium contact time (TLECT). Data were processed with t test.</p><p><b>RESULTS</b>(1) The number of rolling leukocytes from PHM 5 to PHH 8 was increased in EB group and UT group as compared with that at 15 minutes before HEB, especially at PHM 5 [(51.4 +/- 3.2), (24.6 +/- 1.9) cells/min, respectively] which were higher than that in C group [( 1.1 +/- 0.7) cells/min, with t value respectively 59.28, 44.99, P values all below 0.05]. The number in UT group at each time point after burn was less than those in EB group, especially at PHM 5 (t = 27.97, P < 0.05). (2) Compared with that at 15 minutes before HEB, the rolling speed of leukocytes from PHM 5 to PHH 8 was slow in EB group and UT group, especially at PHM 5 [(90 +/- 9), (175 +/- 13) microm/s, respectively] which were slower than that in C group [(277 +/- 12) microm/s, with t value respectively 47.97, 21.59, P values all below 0.05]. The rolling speed in UT group from PHM 5 to PHH 8 was faster than that in EB group, especially at PHM 5 (t = 20.55, P < 0.05). (3) Compared with that at 15 minutes before HEB, the number of leukocytes per 100 micrometer capillary from PHM 5 to PHH 8 was increased in EB group and UT group, especially at PHM 5 (23.27 +/- 3.20, 5.80 +/- 1.61, respectively) which were higher than that in C group (0, with t value respectively 28.16, 13.95, P values all below 0.05). The number of adhered leukocytes in UT group at each time point after burn was less than that in EB group, especially at PHM 5 ( t = 18.89, P < 0.05). (4) Compared with that at 15 minutes before HEB, TLECT from PHM 5 to PHH 8 was increased in EB group and UT group, especially at PHM 5 [(14.45 +/- 1.99), (3.66 +/- 0.96) s/min, respectively] which were longer than that in C group (0 s/min, with t value respectively 28.12, 14.77, P values all below 0.05). TLECT in UT group from PHM 5 to PHH 8 was shorter than that in EB group, especially at PHM 5 (t = 18.91, P < 0.05). (5) No rolling leukocyte or wall-adherent leukocyte was found in blood flow of arterioles or capillaries of rats in three groups at each time point.</p><p><b>CONCLUSIONS</b>Transcranial HEB can lead to abnormal rheological changes of leukocytes in mesentery capillary in rats, and the changes can be ameliorated by ulinastatin.</p>

Alteration in bulbar conjunctiva microcirculation and interventional effect of Pentoxifylline after high-voltage electrical burn in rabbits / 中华烧伤杂志

<p><b>OBJECTIVE</b>To study the changes in bulbar conjunctiva microcirculation (BCM) and the therapeutic effect of Pentoxifylline on BCM disturbance after high-voltage electrical burn (HEB) in rabbits.</p><p><b>METHODS</b>Forty-five rabbits were divided into control group (C), electrical burn group (EB), and Pentoxifylline treatment group (PT) according to random number table, with 15 rabbits in each group. Model of HEB was reproduced in rabbits from EB and PT groups with voltage regulator and experimental transformer. Rabbits in C group were sham injured with the same devices without electrification. Changes in BCM were observed with microcirculation microscope at 15 minutes before HEB and 5 minutes, 1, 2, 4, 8 hour(s) post HEB (PHM or PHH), including: (1) morphology of microvessels, such as the discernible, diameters of arterioles, venules, and capillaries, the unevenness in caliber, and ischemic area; (2) dynamic changes in microvascular blood flow, such as blood flow speed in arterioles, venules, and capillaries, erythrocyte aggregation, and microthrombi formation; (3) condition of tissues surrounding microvessel, such as bleeding and exudation. Measurement data were processed with t test; enumeration data were processed with Fisher's exact test.</p><p><b>RESULTS</b>(1) Morphology of microvessel: discernible of microvessels in EB and PT groups was decreased, but that of PT group was better than that of EB group. At PHM 5, diameter of arterioles, venules and capillaries was respectively (7.3+/-2.5), (12.3+/-2.4), (3.5+/-0.7) microm in EB group, all narrower than those of the control group [(14.6+/-3.1), (27.2+/-3.5), (9.0+/-1.4) microm, with t value respectively 5.23, 13.66, 14.04, P values all below 0.05]. Diameters of the microvessels in PT group [(10.2+/-3.8), (21.5+/-3.1), (7.1+/-1.2) microm] were larger than those in EB group (with t value respectively 2.21, 8.99, 10.18, P values all below 0.05). Diameters of arterioles, venules and capillaries in EB and PT groups recovered to the before HEB size at PHH 1. From PHH 2 to 8, arterioles and capillaries decreased gradually in caliber, venules dilated gradually in EB and PT groups, but the changes in PT group were not obvious. Thickness of microvessel was observed uneven in EB group at PHM 5, which lasted until PHH 8. Ischemia of the tissue was observed in EB group at PHM 5, which improved at PHH 2. Situation in PT group was better. (2) Dynamic changes in microvascular blood flow: at PHM 5, blood flow speed in arterioles, venules and capillaries was respectively (202+/-53), (198+/-44), (46+/-12) microm/s in EB group, all slower than those of the control group [(544+/-37), (359+/-32), (220+/-19) microm/s, with t value respectively 20.47, 11.51, 30.02, P values all below 0.05], and those of PT group [(335+/-42), (260+/-35), (119+/-23) microm/s] were faster than those of EB group (with t value respectively 7.55, 4.26, 14.85, P values all below 0.05). Blood flow speed in EB and PT groups recovered to the before HEB level at PHH 1. From PHH 2 to 8, blood flow speed decreased gradually in EB and PT groups, but that of PT group was faster than that of EB group. Erythrocyte aggregation in venules and capillaries was observed in EB group at PHM 5, which eased up at PHH 1, but aggregated at PHH 2, lasting until PHH 8. Obvious microthrombi were observed in EB group at PHH 2, which increased gradually. These changes were less obvious in PT group. (3) Condition of surrounding tissues of microvessel: in EB group, exudation was observed around microvessels at PHH 1, bleeding at PHH 2, with a worsening tendency. Changes in those in PT group were less obvious.</p><p><b>CONCLUSIONS</b>HEB causes disturbance in BCM, but it can be ameliorated by Pentoxifylline.</p>