Comparative study of clinical efficacy between video-assisted anal fistula treatment and traditional fistula resection plus seton in treatment of complex anal fistula / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To explore the efficacy of video-assisted anal fistula treatment (VAAFT) in treatment of complex anal fistula.</p><p><b>METHODS</b>Clinical data of 87 patients with complex anal fistula undergoing operation at Department of General Surgery, the Second Affiliated Hospital of Suzhou University from September 2015 to December 2016 were collected to conduct a cohort study. The operative procedure depended on economic conditions and patient preference. Patients were divided into VAAFT group (42 cases) and traditional fistula resection plus seton (FRS) group (45 cases). The procedure of FRS was to completely remove the fistula along external wall, the inner opening and surrounding scar tissues, then, the inner opening was closed with absorbable suture. For deeper and more complex fistula, the above procedure should be combined with seton. Based on the concept of endoscopic minimally invasive surgery, VAAFT could deal with the fistula and inner opening under direct vision. The brief steps were as follows: insertion of the anal fistula scope through external opening into the fistula; continuous injection of glycine-mannitol solution to expand and clean the foul fistula; electrocoagulation of all lesions; clearance of burnt tissues from the lumen with endoscopic brush and forceps; injection of medical fibrin glue through the inner opening; closing the inner opening by suture. Intraoperative and postoperative indices were compared between two groups.</p><p><b>RESULTS</b>VAAFT group included 33 males and 9 females with mean age of (37.4±13.5) years, mean BMI of (24.3±3.2) kg/m, and mean disease course of (4.8±3.9) months. Of 42 cases, 5 had preoperative diabetes mellitus, 31 were high fistula and 11 were low fistula. FRS group included 32 males and 13 females with mean age of (42.1±15.6) years, mean BMI of (24.8±3.7) kg/m, and mean disease course of (5.7±3.6) months. Of 45 cases, 4 had preoperative diabetes mellitus, 37 were high fistula and 8 were low fistula. There were no significant differences in baseline data between two groups(all P>0.05). Compared with FRS group, VAAFT group had significantly shorter operative time [(44.6±10.5) minutes vs. (57.4±12.3) minutes, t=5.203, P=0.000], lower incidence of postoperative bleeding (14.3% vs. 33.3%,χ²=4.304, P=0.038), less pain (Visual Analogue Scale,VAS) (2.9±1.8 vs. 7.3±1.2, t=13.500, P=0.000), faster pain relief [(1.0±0.8) days vs. (4.5±1.2) days, t=15.890, P=0.000] and shorter hospital stay [(4.1±3.5) days vs.(7.5±2.3) days, t=5.389, P=0.000]. However, there were no significant differences between two groups in urinary retention rate, first postoperative fecal time and postoperative infection rate(all P>0.05). All patients were followed up for more than 6 months, FRS group had significantly higher incidence of anal incontinence than VAAFT group (20.0% vs. 2.4%, Fisher P=0.015). However, no significant difference in recurrence rate was found between VAAFT and FRS group(7.1% vs. 15.6%, Fisher P=0.317).</p><p><b>CONCLUSIONS</b>Compared to traditional FRS treatment, VAAFT possesses some advantages in less injury, less pain, faster recovery, and lower postoperative anal incontinence rate. Thus, VAAFT is a superior operative choice in treatment of patients with complex anal fistula.</p>

Optimization of Mirabegron Sustained-release Tablets by Central Composite Design-response Surface Meth-od / 中国药房

OBJECTIVE:To optimize the formulation of Mirabegron sustained-release tablets. METHODS:Using polyethylene oxide(PEO)and hydroxypropylmethyl cellulose(HPMC K4M)as the sustained release matrix,Mirabegron sustained-release tab-lets were prepared by powder direct compression technology. Using 1,3,5,7 h accumulative release rate as indexes,the amounts of PEO,HPMC K4M and OPADRY? were optimized by composite design-response surface method,and then validated. Accumula-tive release rates of sustained-release tablet and original tablet (MyrbetriqTM) were compared in different pH mediums (water,pH 1.0 simulated gastric fluid,pH 4.5 acetate buffer solution,pH 6.8 phosphate buffer solution) at different rotation rates (100,50 r/min),and similiar factor f2 was calculated to fit drug release model of sustained-release tablet. RESULTS:In the optimized firmu-lation each Mirabegron sustained-release tablet contained mirabegron 25 mg,PEO 108.02 mg,HPMC K4M 21.69 mg,OPADRY? 2.27%. Relative error of accumulative release rates at 1,3,5,7 h to predicted value were 4.78%,3.48%,0.69% and -1.41%, respectively. f2 of release curves of sustained-release tablet and original tablet were higher than 65 in different pH medium at differ-ent rotation rates. The drug release of sustained-release tablet was fitted to zero-order release equation. CONCLUSIONS:Mirabe-gron sustained-release tablet by optimized technology is similar to original tablet in drug release behavior.