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Objective: 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., Methods: 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., Results: (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., Conclusions: HEB causes disturbance in BCM, but it can be ameliorated by Pentoxifylline.

Objective: To observe the changes in surface microcirculation of pancreas after high-voltage electric burn (HEB)., Methods: Thirty rabbits were divided into electrical injury (E) group and control (C) group in a simple random method, with 15 rabbits in each group. Rabbit model of HEB was reproduced from E group with TC-30-20KVA type voltage regulator and YDJ-10KVA type experimental transformer. Rabbits in C group were shamly burned with the same equipment as in E group but not electrified. Intravenous blood of rabbits in both groups was drawn 15 mins before HEB and 0, 1, 2, 4, 8 h after to determine the levels of serum amylase and blood glucose. The morphology of the pancreas microvessels and its surrounding tissues, and the dynamic changes in microvascular blood flow were observed with WX-9 microscope and its image analytical system., Results: The level of serum amylase of rabbits in E group increased gradually and peaked (849 +/- 39) U/L at 8 post HEB h (PHH), which decreased gradually reaching the nadir (153 +/- 21) U/L at 8 PHH in C group (P < 0.05). The blood glucose levels of rabbits in E group and C group increased gradually, with the former level obviously higher than the latter (P < 0.05). Arteriole, venule and capillary network on the surface of pancreatic lobules of rabbits in both groups were clearly seen and well-distributed in the natural way before HEB. In E group, arterioles of rabbits contracted at 0 PHH, and increased gradually in caliber size at 1 PHH; venules of rabbits were unevenly thickened at 2 PHH, and dilated at 8 PHH; the capillaries were contracted or with interrupted flow or completely obstructed at 0 PHH, and their thickness were uneven at 2 PHH, showing exudation at 8 PHH. There was no obvious change of microvessels in rabbits in C group at each time point. There was no exudation and bleeding around the microvessels on the pancreas surface of rabbits in both groups before HEB. In E group exudation was observed around microvessels at 1 PHH, bleeding was observed at 2 PHH and became obvious at 4 PHH; exudation and diffuse bleeding from capillaries were observed at 8 PHH. There was no exudation and bleeding in rabbits in C group as observed at each time point. Before HEB, blood flow speed in microvessels of rabbits in 2 groups was similar to each other (P > 0.05), and no erythrocyte aggregation or microthrombus was found in both groups. In E group, blood flow speed slowed down at 0 PHH as compared with that before HEB, it accelerated at 1 h and slowed down later; erythrocyte aggregation in venules and capillaries was found at 0 PHH, and it aggregated gradually. No above-mentioned change was found in C group., Conclusions: HEB produces microcirculation disturbance and functional disturbance of pancreas.

Objective: To explore the optimal method for the treatment of the elbow joint stiffness accompanied with neural injury after electrical injury., Methods: Thirty adult cadaver elbows were fixed and dissected to observe the attachments of the ligaments and the muscles around the joint, and its relationship with the major nerves. Ten patients with electric burns with stiffness of the elbow joint were treated by means of loosening the anterior and posterior fascicles of radial and ulnar collateral ligaments, at the same time down shifting the insertion of flexor muscles, replacing the ulnar nerve anteriorly, in order to reconstruct flexor and extension functions of the elbow. The effect was evaluated with biomechanics criteria., Results: Through anatomical study, it was revealed that contracture of the posterior fascicles of the radial and ulnar collateral ligaments and triceps brachii muscle would result in stiffness of the elbow joint, and contracture due to disuse of the two anterior fascicles of the radial and ulnar collateral ligaments and M.biceps brachii would produce flexion deformity of the elbow joint. Postoperatively, the functions of the elbow joints of all the 10 patients recovered satisfactorily. Follow-up from 1 to 3 years showed no change in the range of flexion and extension movements of the elbows, and on the contrary, mobility of the elbow joints was improved., Conclusion: Loosening of the anterior and posterior fascicles of the two collateral ligaments and replacement of insertions of biceps and triceps are pivotal in the treatment of stiffness of the elbow joint. Meanwhile lowering the origins of forearm flexor muscles on epicondylus and replacing anteriorly the ulnar nerve can further improve the flexion, function of the joint and relieve compression of the nerve.

Objective: To explore the pathological and myoelectric-physiological changes and the mechanism of the early postburn sciatic nerve injury by high voltage electricity in rabbits., Methods: Apparatus producing high electricity was established with a special-designed microrecorder of digital reserve. The electrical current values were determined by computer responsive analysis system with the concomitant determination of myoelectric-physiology and pathomorphology., Results: When the current was set to be 50 HZ, the average indentical resistance value of the nerve tissue was (5.99 +/- 0.88) k omega and the average current value was 83.5 mA/cm2. There exhibited different degrees of sciatic nerve injury when examined by myoelectric-physiological and pathophysiological measures., Conclusion: Peripheral nerve could be injured by current of high voltage electricity.

Objective: To explore the characteristics and the mechanism of the injury of Schwann cells and nerve fibres of the peripheral nerves inflicted by high voltage electricity., Methods: Rabbits injured by high voltage electricity were employed as the model. Thirty rabbits were randomly divided into control (9) and experimental (21) groups. The dynamic quantitative DNA analysis and the change of the morphology and structure of the sciatic nerve were observed with LM and EM on 0, 3, 7, 10, 14 and 21 postburn days (PBDs), respectively., Results: There was continuous degeneration of the axon and medullary sheath of sciatic nerve tissue and its neogenesis was inhibited. The DNA synthesis in Schwann cell initiated on 3 postburn day (PBD). The distribution of the current was heterogeneous on the cross section of peripheral nerve fibres., Conclusion: The obvious features of peripheral nerve injured by high voltage electricity included delayed initiation of the DNA synthesis of Schwann cell and the secondary necrosis and inhibition of neogenesis process of Schwann cell.

Objective: To summarize the experience with clinical emergent comprehensive repair of electrical injury., Methods: One hundred fifty five cases of electrical injury during past 14 years were analyzed in terms of the emergent repair methods on the basis of medical records and photographs., Results: In this group of patients the average interval between injury and hospitalization was 14.9 +/- 21.5 hours, And 108 cases (70%) were admitted to hospital within 2 hours post injury. The average time between admission and first operation was 3.74 +/- 9.89 hours, and 70% of them was within 1 hour after admission. Four hundred and fifty nine wounds were debrided and 296 strips of tendons, 19 strips of blood vessels, 196 pieces of bone or joints and 16 strips of nerves, which were exposed, devitalized or necrotic, were saved. The grafting repair of tendons, bones, nerves and blood vessels was done in 24 case times. Three hundred and ninty eight tissue flaps were employed in 459 wounds. CLS (NS + Lidocaine + amphicol) solution was employed to irrigate underneath the flaps for 24 similar 96 hours or longer. Composite dan -- shen root (scatellaira indica) solution was given to all the patients by injection. As a result, the excellent rate of function and contour was 84.8%. The unsatisfactory and amputation rate was 9.6%. The rate of extremity and/or finer amputation was 1.8%. The rate of total limb loss including those lost instantly after injury was 9%., Conclusion: Emergent comprehensive management of electrical injury was a feasible and effective method for decreasing extremity loss.

Objective: To establish a rabbit model of non-thermal high voltage electrical injury, which was accompanied by progressive tissue necrosis for the further study of electrical injury., Methods: Seventy-five New Zealand rabbits were employed, in which 45 were used for the selection of the size of electrode plate, the inflicting time, the intervals and the injury degree. Five groups of rabbits were used for the study of the model. The study was carried out by means of clinical anatomical exploration, categorization by the Index of Deep Burn Injury (IDBI) and (99)Tc(m)-MDP isotope scanning and gamma photography., Results: The optimal injury indices selected were as follows: the electric field strength was 17 000 volts/m, the mean current intensity was 554 mA, and the average current density was 137 mA/cm(2) for small electrode and 21 mA/cm(2) for big one, and average increase of tissue temperature was 1.73 degrees C during injury process. This excluded the possibility of thermal injury. Five models were created, i.e. mild, moderate, severe, extra severe and destructive ones. There was no obvious cutaneous necrosis. Nevertheless, there was loss of injured extremities on 5th, 7th and 12th post-injury days in the severe, extra severe and destructive groups., Conclusion: Non-thermal factor was the major cause of electric injury in the model with typical clinical features.

Objective: To observe the histomorphological changes in canine heart after electrical injury., Methods: Light and electronic microscopes (LM, EM) were employed to observe the histomorphological changes in canine heart after electrical injury., Results: There were swelling and deformation of pacemaker cells (p cells) and mitochondrial swelling and vacuolization in cardiac conduct system. The cardiac muscle cells in the atrial and the ventricular walls exhibited obvious swelling and deformation, blurred cross striation, intracytoplasmic structural destruction of myofibrils, messy microfilaments, mitochondrial swelling, vacuolization and even dissolution. Furthermore, there was also breaking and expanding of the intercalated disk between adjacent cardiac muscle cells. The gap junctions at sites of intercalated disk were disrupted., Conclusion: The pathomorphological characteristics of cardiac histological changes after electrical injury were similar to those of acute myocardial infarction.