Effects of Umbilical Preparation Before Trans-umbilical Laparo-endoscopic Single-site Surgery on Umbilical Wounds Healing: a Randomized Controlled Trial.

OBJECTIVE: The umbilicus is the only anatomic entrance and incision site for trans-umbilical laparoendoscopic single-site surgery (TU-LESS). Data on incisional surgical site infections (ISSI) and incision healing in TU-LESS are lacking. Therefore, we aimed to observe umbilical incision healing and possible hernia after TU-LESS and explore the efficacy of preoperative umbilicus preparation on ISSI. SUBJECTS AND METHODS: Consecutive patients aged 18 to 65 years, who were scheduled to undergo TU-LESS at a teaching hospital between March 2020 and November 2021, were enrolled in this prospective study. All patients were randomized to the study group with preoperative umbilicus preparation 30 minutes before patients were sent to the operating room and to the control group without preparation. The umbilical dimple was disinfected twice using povidone-iodine in both groups before the skin incision. The primary outcome was ISSI within 30 days of surgery. Umbilical hernia at 3 months after surgery and perioperative data such as operation time, complications, and incision healing were recorded and compared. RESULTS: A total of 400 patients were recruited for this study. TU-LESS was performed in all patients without major complications. ISSI occurred in 5 patients in the study group (2.5%) and 3 patients in the control group (1.5%), with no significant differences between both groups ( P =0.479). No umbilical hernia occurred in any patient during the 3 months follow-up. Six patients in the study group (3.1%) and 1 in the control group (0.5%) experienced excessive scarring, a relatively high incidence in the study group, though the difference was not statistically significant ( P =0.067). CONCLUSIONS: TU-LESS-related umbilical hernias are rare with existing suturing methods. Umbilicus preparation before TU-LESS could not decrease ISSI; however, it increased the nursing workload, which should be avoided.

[Phosphorus Fractions and Release Risk in Surface Sediments of an Agricultural Headwater Stream System in Hefei Suburban, China].

A typical water system of agricultural headwater stream in Chaohu Lake basin was selected as the study area, and 17, 16, 14 and 13 surface sediments were collected from the four styles of stream, respectively, including ponds, branches, main channel and mainstream deep pools, in October 2014 (in autumn) and April 2015 (in spring). The forms and space-time variations of phosphorus in the sediments were analyzed. Clustering and variance analysis were conducted on the phosphorus forms data from the four styles of stream by means of multivariate statistical analyses. We quantified the phosphorus release risk (PSI) and identified the main impact factors of PSI via calculating the phosphorus sorption index (PSI) and the correlation analysis. The results showed that: (1) The contents of TP in the surface sediments ranged from 137.517 to 1709.229 mg x kg(-1) with an average value of 532. 245 mg x kg(-1), and the order of the average contents of phosphorus forms was IP (350.347 mg x kg(-1)) > OP (167.333 mg x kg(-1)) > Fe/Al-P ( 78. 869 mg x kg(-1)) > Ca-P (56.343 mg x kg(-1)) > Ex-P (6.609 mg x kg(-1)); (2) The contents of phosphorus forms had the same trend in all the four stream styles, which was deep pool > main channel > branch > pond; (3) In autumn, the deep pool and main channel were clustered into one class, while the pond and branch were clustered into the other class. In spring, branch, main channel and deep pool were clustered into the same class; (4) Variance analysis showed that the differences among the four stream styles were larger in autumn than in spring; (5) The PSI of the surface sediments ranged between 24.49 and 69.94 (mg x L(-1) x (100 g x micromol)(-1). The PSI in spring was lower than that in spring, indicating that phosphorus release risk of surface sediment was higher in spring than in autumn. (6) PSI had a significant negative correlation with Ex-P, IP and pH.