ObjectiveTo specify the specific wind environment conditions of the outdoor wind speed field and wind pressure field in Wuhan Huoshenshan Hospital, identify the epidemic prevention area under special conditions such as daily cleaning and disinfection as well as accidents, and provide technical references for epidemic prevention work.MethodsThe network open data were adopted to build 3D models of buildings in Wuhan Huoshenshan Hospital and surrounding areas by using Auto CAD 2008 software, and then PHOENICS 2011 software was used to parameterize settings to simulate winter outdoor wind speed and wind pressure fields, to identify the epidemic prevention area under special conditions such as daily cleaning and disinfection as well as accidents.ResultsIn the prevailing wind direction, the speeds of wind towards the No. 1 building, the intensive care unit and the reception area for confirmed patients transferred by ambulance, the No.2 building, and the temporary storage room of the isolation medical area are 1.0−1.5, 2.5−3.0, 2.0−2.5, and 3.0−3.5 m/s, respectively; the speed of wind towards the living area for medical staff is 2.5 m/s. In the isolation medical area, the pressure difference between the windward side and the leeward side of the building in the first row of the windward side is ≥5 Pa, and those of the rest buildings are ≥0.5 and ≤5 Pa; in the living area for medical staff, the pressure difference between the windward side and the leeward side of the north of the building is ≥5 Pa, while that of the south of the building is ≤0.5 Pa.ConclusionOn the whole, there are areas with poor ventilation and at risk of pollutants gathering in Wuhan Huoshenshan Hospital, so the daily cleaning and disinfection work and epidemic prevention work of accident and other special circumstances should be done well.
Objective To observe the revascularization process of transplanted nerve after transplantation of long nerve and accompanying peri pheral vessels, to investigate its relationship with nerve regeneration. Methods The mediannerve defect models of the left forelimb (3 cm in length) were made in 60 New Zealand rabbits (aged 6-8 months, weighing 2.0-2.5 kg, and male or female), which were randomly divided into 2 groups (n=30). In situ anastomosis of the median nerves was performed in the control group; in situ anastomosis of the median nerves was made in parallel to the surrounding elbow veins, the transplanted epineurium and the adventitia were sutured with nerve anastomosis l ine in the experimental group. After operation, the gross observation, electrophysiological testing, and histopathology observation was performed at 1, 2, 4, 8, and 12 weeks, and transmission electron microscope at 12 weeks to observe the revascularization of nerve grafts, nerve fiber regeneration, and functional recovery. Results In the experimental group, revascularization was observed at 1 week after operation, and the degree of revascularization was significantly higher than that in the control group at 2, 4, 8, and 12 weeks. At 8 and 12 weeks, the nerve fiber regeneration speed, quality, and quantity in the experimental group were better than those in the control group. At 2, 4, 8, and 12 weeks, the nerve conduction velocities were (10.32 ± 0.94), (13.14 ± 1.22), (22.68 ± 1.16), and (24.09 ± 1.27) m/ s respectively in the experimental group, and were (9.18 ± 1.07), (11.12 ± 1.03), (19.81 ± 1.37), and (20.67 ± 1.19) m/s in the control group, showing significant difference at 12 weeks after operation (t=3.167, P=0.001). At 12 weeks in the experimental group, the myel in sheath had similar size, less sheath plate delamination, normal Schwann cells and rich organelles, in which normal microfilaments, microtubules and axonal mitochondria were observed; axonal mitochondria had clear crestfilm and no swelling and vacuolization, and the neurofibrils basically became normal. The myelinated nerve fibers area, myelin thickness, and axon diameter were (5.93 ± 0.94) mm2, (0.72 ± 0.12) μm, and (3.12 ± 0.12) μm respectively in the experimental group, and were (5.28 ± 0.72) mm2, (0.65 ± 0.09) μm, and (2.98 ± 0.16) μm respectively in the control group, all showing significant differences (t=3.736, P=0.002; t=3.271, P=0.002; t=4.533, P=0.001). Conclusion The transplanted nerves in parallel to large blood vessels can promote angiogenesis of the transplanted nerve, and accelerate the regeneration and functional recovery of the nerves.
Objective To research the effects of vascular endothelial growth factor (VEGF) on the survival of reverse flow axial skin flaps. Methods A 8 cm×2 cm full thickness transverse dorsal flap based on right deep circumflex iliacartery was elevated in 20 SpragueDawley rats, which length crossing midline was 4.0 cm. The rats were randomized into two groups:experimental group (n=10), subcutaneous VEGF injections into the flap (200 ng, 200 μl) after flap elevation; controlgroup (n=10), subcutaneous saline injections into the flap (200 μl) after flap elevation. The flap was immediately sutured to its recipient beds then the injection was executed. Seven days after operation, the survival area of flaps and density of vessels were observed and measured, meanwhile its histological representation of the flaps was examined. Results After 7 days of recovery, the mean survival area of flaps was 15.55±0.27 cm2 in experimental group and 13.42±0.57 cm2 in control group. The difference was significant between experimental group and control group (P<0.01). The mean vessel density of flaps was 21.00±3.16 in control group and 34.40±3.75 in experimental group. The difference was significant between experimental group and control group (P<0.01). Histological analysis demonstrated that a qualitatively greater amount of granulation tissue, regular collagen fiber and a lot of fibrillated cells were observed in experimental group. Erythrocytes were leaked outfrom vessels, and inflammatory cells were observed around in control group. Conclusion In early survival of flaps, the VEGF can improve the survival of areverse flow axial skin flap through improving angiogenesis and increasing the perfusion of vessel. It is an effective method of improving the survival of reverse flow axial skin flaps that VEGF is fully injected in subcutaneous flaps by single, when flaps are elevated.
OBJECTIVE: To study the effective protective measures to ensure sufficient blood supply to the jejunal segment in reconstruction of esophagus. METHODS: According to evidence based on medicine, we analyzed retrospectively 69 patients (48 cicatricial stenosis due to chemical burn, 21 defects due to excision of esophagus cancer), whose esophagus were reconstructed with free jejunal graft(in 28 cases) and with pedicle jejunal graft (in 41 cases) from 1980 to 2001. RESULTS: All patients were followed up for 1-21 years. Of 43 patients treated before 1996, 5 complicated by anastomotic leakage, 1 by strangulated intestinal obstruction; of 26 patients treated after 1996 (6 with free jejunal graft, 20 with pedicle jejunal graft), only one case complicated by anastomotic leakage. CONCLUSION: The preservative measures for good blood supply to the jejunal segment include the following aspects: (1) complete marginal vascular arcade without tension in the mesojejunum; (2) vessel anastomosis smooth; (3) 4-finger width pathway of jejunum; (4) the stable arterial blood pressure (more than 8 kPa); (5) a single-row anastomosis; and (6) the comprehensive preoperative management.
Objective To assess the effectiveness of a novel minimally invasive Achilles tendon suture instrument in the treatment of fresh closed Achilles tendon rupture. Methods A retrospective study was conducted on 150 patients who underwent surgical intervention for fresh closed Achilles tendon rupture. Eighty patients were treated with the novel minimally invasive Achilles tendon suture instrument (minimally invasive group) and 70 patients with traditional open surgery (traditional group). The two groups were comparable in terms of gender, age, injured side, cause of injury, the interval between injury and operation, and the distance from the fracture end to the calcaneal tuberosity (P>0.05). The operation time, intraoperative blood loss, incision length, hospital stays, hospitalization expenses, and complications were recorded and compared. At 1 year after operation, the ankle joint function was evaluated by the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score. Results The minimally invasive group demonstrated significantly shorter operation time, smaller incision length, and lower intraoperative blood loss when compared with the traditional group (P<0.05). However, there was no significant difference in terms of hospital stays and hospitalization expenses between the two groups (P>0.05). All patients were followed up 12-24 months after operation (mean, 15.5 months). In the traditional group, 6 cases of incision necrosis and 7 cases of Achilles tendon adhesion occurred, while in the minimally invasive group, all incisions healed at first intention and no Achilles tendon adhesion occurred. The differences in the incidences of the two complications between the two groups were significant (P<0.05). At 1 year after operation, the AOFAS ankle-hindfoot score in the minimally invasive group was superior to that of the traditional group (P<0.05). Conclusion In comparison with traditional open surgery, the use of self-designed novel minimally invasive Achilles tendon suture instrument proves to be an ideal technique for treating fresh closed Achilles tendon ruptures. This approach offers the benefits of smaller incisions, fewer complications, and better postoperative functional recovery, without increasing hospital costs.