Application research of presacral space drainage tube combined with subcutaneous vacuum pressure suction in the laparoscopic-assisted abdominoperineal resection / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To study the management for the perineal incision after laparoscopic-assisted abdominoperineal resection for rectal cancer.</p><p><b>METHODS</b>Clinical data of 87 patients undergoing laparoscopic Miles operation for lower rectal cancer from June 2009 to February 2014 were collected and studied. Presacral space drainage group: presacral space drainage tube was applied in 42 patients. Combined drainage group: presacral space drainage tube combined with subcutaneous vacuum pressure suction was applied in 45 cases. In combined drainage group, except the presacral drainage tube, another drainage tube was placed subcutaneously and connected to a negative pressure ball, which was fixed on the lateral anterior of perineal wound by the further incision and drainage. After subcutaneous tube was placed for 2 weeks, as drainage fluid was limpid and <15 ml/d for 3 days, meanwhile no obvious pelvic fluid was detected by ultrasound, and the wound healed quite well without redness and edema, then the subcutaneous tube with the negative pressure ball could be removed.</p><p><b>RESULTS</b>There were 51 males and 36 females with the mean age of 26-78(56.9±10.8) years old. The laparoscopic Miles operation was successfully completed in all the cases without death and complications. The drainage tube was placed for 4-13(8.0±2.5) days in presacral space drainage group, and for 4-14(6.7±2.4) days in combined drainage group. The subcutaneous tube was placed for 14-24(15.8±3.0) days. The primary healing rate of perineal wound in presacral space drainage group and combined drainage group was 66.7%(28/42) and 91.1%(41/45) respectively, while the perineal wound infection rate was 21.4%(9/42) and 4.4%(2/45) respectively, whose differences between two groups were both significant (χ=7.911, P=0.005 and χ=5.674, P=0.017).</p><p><b>CONCLUSION</b>Presacral space drainage tube combined with subcutaneous vacuum pressure suction in laparoscopic-assisted abdominoperineal resection for rectal cancer has better efficacy and lower infection rate for perineal incision, which is worth wide application.</p>

Clinical application of self-designed guide for percutaneous placement of lumbosacral pedicle screws in surgery of lumbar vertebral fracture / 中华创伤骨科杂志

Objective To evaluate our self-designed guide used clinically in percutaneous placement of lumbosacral pedicle screws in surgery of lumbar vertebral fractures.Methods From May 2012 to March 2015,143 patients with lumbar vertebral fracture were treated with reduction and fixation using percutaneous lumbosacral pedicle screws in our department.Percutaneous placement of lumbosacral pedicle screws was assisted by our self-designed guide in 69 of them(guide group) but not in the other 74 cases (manual group).The 2 groups were compatible in preoperative general data (P ＞ 0.05).The 2 groups were compared in terms of localization time for a single screw,puncture accuracy,times of intraoperative fluoroscopy,operation time,intraoperative blood loss,and hospital stay.Results The guide group had significantly better localization time for a single screw,puncture accuracy,times of fluoroscopy and operation time than the manual group (P ＜ 0.05),but the 2 groups showed no significant differences in intraoperative blood loss and hospital stay (P ＞ 0.05).The guide group obtained an average follow-up of 12.9 months (from 12 to 16 months) while the manual group obtained an average follow-up of 13.2 months (from 12 to 18 months).All fractures healed primarily,without complications like injuries to nerve root or dural sac.Conclusion Our self-designed guide is recommendable because it can obviously improve accuracy of placement of lumbosacral pedicle screws,shorten operation time,and decrease times of intraoperative fluoroscopy.

The appraisal of mechanical properties and friction coefficient of PVA hydro-gel / 生物医学工程学杂志

Gelatin and hydroxyapatite were introduced to polyvinyl alcohol (PVA) hydrogel with an attempt to enhance the performances of PVA hydrogel. Through a reiterative freezing-thawing methods, three kinds of PVA composite hydrogels were prepared. The mechanical performances of these composite hydrogels with the same PVA and HA content but varying gelatin content, such as tensile strength, elasticity modulus, creep curve, relaxation curve and friction coefficient were evaluated by using a computer-controlled universal electronic mechanical testing machine and a UMT-II frictional testing machine. The additional effects of hydroxylapatite and varying gelatin on the performances of composite PVA hydro-gels were analyzed. It was found that the gelatin content directly influenced the physical performances of PVA composite hydrogels; but no linear relationship was recorded. PVA composite hydrogel containing 2wt-% gelatin gave optimal results, i.e. tensile strength of 5.5MPa, compressive elastical modulus of 1.48MPa, creeping rate of 31% in 45 minutes, stress relaxing rate of 40.3%, and the starting friction coefficient of 0.332.