Residual choledocholithiasis after choledocholithotomy T-tube drainage: what is the best intervention strategy?

BACKGROUND: The best intervention approach for residual choledocholithiasis after choledocholithotomy T-tube drainage remains controversial, especially during the period of indwelling T tube and the formation of a sinus. The purpose of the study was to estimate the effects of two therapeutic modalities, namely endoscopic retrograde cholangiopancreatography (ERCP) and choledochfiberscope via the T-tube sinus tract (CDS) on residual choledocholithiasis after choledocholithotomy T-tube drainage. METHODS: A total of 112 patients with residual choledocholithiasis after choledochotomy were included in the study, 50 of which underwent ERCP and 62 patients experienced choledochoscopy via the T-tube sinus tract. The primary outcome measures included the success rate of remove biliary stones, T-tube drainage time, and the average length of hospital stay. The secondary objective was to consider incidence of adverse events including cholangitis, bile leakage, T-tube migration, pancreatitis, bleeding and perforation. After hospital discharge, patients were followed up for two years and the recurrence of choledocholithiasis was recorded. RESULTS: There was no significant difference in the success rate of stone removal between the two groups. Compared to CDS group, T-tube drainage time and the average length of hospital stay was significantly shorter in the ERCP group. The incidence of complications (cholangitis and bile leakage) in the ERCP group was lower than that in the CDS group, but there was no statistically significant difference. When the T-tube sinus tract is not maturation, ERCP was the more appropriate endoscopic intervention to remove residual choledocholithiasis, particularly complicated with cholangitis at this time period. CONCLUSIONS: ERCP is a safe and effective endoscopic intervention to remove residual choledocholithiasis after choledocholithotomy T-tube Drainage without the condition of T-tube sinus tract restriction.

New theoretical investigation of mechanism, kinetics, and toxicity in the degradation of dimetridazole and ornidazole by hydroxyl radicals in aqueous phase.

Dimetridazole (DMZ) and ornidazole (ONZ) have been widely used to treat anaerobic and protozoal infections. The residues of DMZ/ONZ persist in the water environment. The mechanisms and kinetics of hydroxyl-initiated oxidation, the primary DMZ/ONZ degradation method, were evaluated by quantum chemical methods.·OH-induced degradation of DMZ and ONZ shared many mechanistic and kinetic characteristics. The most feasible degradation pathway involved forming OH-imidazole adducts and NO2. The OH-imidazole adducts were subsequently degraded into double·OH imidazole intermediates. The rate coefficients for·OH degradation of DMZ and ONZ were 4.32 × 109 M-1 s-1 and 4.42 × 109 M-1 s-1 at 298 K, respectively. The lifetimes of DMZ and ONZ treated with·OH at concentrations of 10-9-10-18 mol L-1 at 298 K were τDMZ = 0.231-2.31 × 108 s and τONZ = 0.226-2.26 × 108 s, respectively. Toxicity assessment showed that the first degradation products of DMZ and ONZ exhibited enhanced aquatic toxicity, whereas most of the secondary degradation products were not harmful to aquatic organisms. Some of transformation products were still developmental toxicant or mutagenicity positive.

Theoretical Calculation on the Reaction Mechanisms, Kinetics and Toxicity of Acetaminophen Degradation Initiated by Hydroxyl and Sulfate Radicals in the Aqueous Phase.

The •OH and SO4•- play a vital role on degrading pharmaceutical contaminants in water. In this paper, theoretical calculations have been used to discuss the degradation mechanisms, kinetics and ecotoxicity of acetaminophen (AAP) initiated by •OH and SO4•-. Two significant reaction mechanisms of radical adduct formation (RAF) and formal hydrogen atom transfer (FHAT) were investigated deeply. The results showed that the RAF takes precedence over FHAT in both •OH and SO4•- with AAP reactions. The whole and branched rate constants were calculated in a suitable temperature range of 198-338 K and 1 atm by using the KiSThelP program. At 298 K and 1 atm, the total rate constants of •OH and SO4•- with AAP were 3.23 × 109 M-1 s-1 and 4.60 × 1010 M-1 s-1, respectively, considering the diffusion-limited effect. The chronic toxicity showed that the main degradation intermediates were harmless to three aquatic organism, namely, fish, daphnia, and green algae. From point of view of the acute toxicity, some degradation intermediates were still at harmful or toxic level. These results provide theoretical guidance on the practical degradation of AAP in the water.