Preoperative bowel preparation does not favor the management of colorectal anastomotic leak

BACKGROUND Controversy exists regarding the impact of preoperative bowel preparation on patients undergoing colorectal surgery. This is due to previous research studies,which fail to demonstrate protective effects of mechanical bowel preparation against postoperative complications. However, in recent studies, combination therapy with oral antibiotics(OAB) and mechanical bowel preparation seems to be beneficial for patients undergoing an elective colorectal operation.AIM To determine the association between preoperative bowel preparation and postoperative anastomotic leak management(surgical vs non-surgical).METHODS Patients with anastomotic leak after colorectal surgery were identified from the 2013 and 2014 Colectomy Targeted American College of Surgeons National Surgical Quality Improvement Program(ACS-NSQIP) database and were employed for analysis. Every patient was assigned to one of three following groups based on the type of preoperative bowel preparation: first groupmechanical bowel preparation in combination with OAB, second groupmechanical bowel preparation alone, and third group-no preparation.RESULTS A total of 652 patients had anastomotic leak after a colectomy from January 1,2013 through December 31, 2014. Baseline characteristics were assessed and found that there were no statistically significant differences between the three groups in terms of age, gender, race, American Society of Anesthesiologists score,and other preoperative characteristics. A χ~2 test of homogeneity was conducted and there was no statistically/clinically significant difference between the three categories of bowel preparation in terms of reoperation.CONCLUSION The implementation of mechanical bowel preparation and antibiotic use in patients who are going to undergo a colon resection does not influence the treatment of any possible anastomotic leakage.

Quantitative analysis of Pb adsorption on sulfhydryl-modified biochar

Biochar is an effective absorbent for remediating heavy metal contaminated soil,but functional optimization is still needed to improve its performance in field application.Here,we characterized the physical structures and surface chemical properties of raw wood biochar and palm biochar(WB and PB)and the corresponding sulfhydryl-modified biochar(SWB and SPB).Their adsorption capacity for Pb was evaluated by combining thermodynamic and kinetic adsorption at 0.01 mol/L KCl and corresponding model simulation.The results demonstrated successful grafting of sulfhydryl groups onto the biochar,which dramatically reduced the specific surface area(SSA)and pore volume of biochar.The pKa in the surface complexation model(SCM)indicated similar proton affinity between sulfhydryl groups and original functional groups on the biochar.SCM could satisfactorily fit the Pb adsorption behaviors,and model analysis revealed that Pb tended to be adsorbed on low-proton affin-ity sites at low pH,but high-proton affinity sites became dominant in Pb adsorption with increasing pH and adsorbed almost all Pb ions at pH>7.0.Besides,the Pb adsorption density of SWB and SPB was improved by 8.86 and 3.64 folds relative to that of WB and PB,respectively.Over 90% of initially added Pb ions were removed in 1440 and 720 min by raw and sulfhydryl-modified biochar,respectively,indicating that sulfhydryl modification accelerated the Pb adsorption of biochar.These results suggest that site density,SSA and pore structure of biochar play crucial roles in heavy metal adsorption,and sulfhydryl modification may improve the performance of biochar in remediating heavy metal contaminated soil.

Phenotypic ASCOD characterisations of ischaemic stroke in the young at an urban tertiary care centre

Background and purpose Stroke in young individuals is a serious public health burden.This study aimed to characterise the various phenotypes of ischaemic stroke in a young urban population(≤50 years old)using the ASCOD classification system,which assigns a score to five stroke categories:atherosclerosis,small vessel disease(SVD),cardioembolism,other and dissection.Within each category,a numerical score represents the degree of causality attributed to the stroke.Methods This retrospective study cohort was composed of patients from an urban tertiary care academic centre.Cases were selected by searching Get With the Guidelines database for adults≤50 years old with ischaemic stroke.The study sample included 175 ischaemic strokes in 157 patients,with 16 subjects re-infarcting.Using retrospective chart review,each stroke was scored according to the ASCOD classification system.Multivariable logistic regression analyses were performed to explore each ASCOD category’s association with causal risk factors.results Of possible causal mechanisms,defined as receiving a grade 1 or 2,a cardiovascular aetiology was most prevalent(25.7%),followed by SVD(22.3%),and closely by atherosclerosis(21.1%).Of general phenotypes,defined as receiving a grade 1 or 2 or 3,atherosclerosis was the most prevalent(51.4%),followed by SVD(47.4%),cardioembolism(42.3%)and other(35.4%).31.6%of all strokes were of unclear aetiology.Subjects between 45 and 50 years old were more likely to develop a cardioembolic or SVD stroke when compared with subjects<45 years old.Conclusion This study took a novel approach to ASCOD phenotyping,allowing several observations:(1)In patients with advanced atherosclerosis receiving the score A1,the vast majority had systemic atherosclerosis in multiple vascular territories;(2)the cardiac score C2(6),defined as a radiographic pattern highly suggestive of a central embolic source,may overestimate the prevalence of true cardiac disease;(3)incidental laboratory findings may detect some underlying pathology,but causality to the stroke is unlikely.