Jamie A. Cannon

Preoperative oral antibiotics reduce surgical site infection following elective colorectal resections.

BACKGROUND: Surgical site infection is a major cause of morbidity after colorectal resections. Despite evidence that preoperative oral antibiotics with mechanical bowel preparation reduce surgical site infection rates, the use of oral antibiotics is decreasing. Currently, the administration of oral antibiotics is controversial and considered ineffective without mechanical bowel preparation. OBJECTIVE: The aim of this study is to examine the use of mechanical bowel preparation and oral antibiotics and their relationship to surgical site infection rates in a colorectal Surgical Care Improvement Project cohort. DESIGN: This retrospective study used Veterans Affairs Surgical Quality Improvement Program preoperative risk and surgical site infection outcome data linked to Veterans Affairs Surgical Care Improvement Project and Pharmacy Benefits Management data. Univariate and multivariable models were performed to identify factors associated with surgical site infection within 30 days of surgery. SETTINGS: This study was conducted in 112 Veterans Affairs hospitals. PATIENTS: Included were 9940 patients who underwent elective colorectal resections from 2005 to 2009. MAIN OUTCOME MEASURE: The primary outcome measured was the incidence of surgical site infection. RESULTS: Patients receiving oral antibiotics had significantly lower surgical site infection rates. Those receiving no bowel preparation had similar surgical site infection rates to those who had mechanical bowel preparation only (18.1% vs 20%). Those receiving oral antibiotics alone had an surgical site infection rate of 8.3%, and those receiving oral antibiotics plus mechanical bowel preparation had a rate of 9.2%. In adjusted analysis, the use of oral antibiotics alone was associated with a 67% decrease in surgical site infection occurrence (OR=0.33, 95% CI 0.21–0.50). Oral antibiotics plus mechanical bowel preparation was associated with a 57% decrease in surgical site infection occurrence (OR=0.43, 95% CI 0.34–0.55). Timely administration of parenteral antibiotics (Surgical Care Improvement Project-1) had a modest protective effect, with no effect observed for other Surgical Care Improvement Project measures. Hospitals with higher rates of oral antibiotics use had lower surgical site infection rates (R2 = 0.274, p < 0.0001). LIMITATIONS: Determination of the use of oral antibiotics and mechanical bowel preparation is based on retrospective prescription data, and timing of actual administration cannot be determined. CONCLUSIONS: Use and type of preoperative bowel preparation varied widely. These results strongly suggest that preoperative oral antibiotics should be administered for elective colorectal resections. The role of oral antibiotics independent of mechanical bowel preparation should be examined in a prospective randomized trial.

Colorectal Cancer Screening

During the past decade we have seen dramatic advances in colon cancer screening. Reduction in mortality in average risk screening for colorectal cancer has now been shown in multiple trials. Efforts to increase public awareness and compliance with evidence-based screening guidelines are underway. Recent guidelines have incorporated family history, as it has been identified as a common risk factor. The genes responsible for the inherited syndromes of colon cancer have been identified and genetic testing is available. Currently, screening the average risk population over the age of 50 would reduce mortality from colon cancer by 50%. Future advances will likely include improved screening tests, and the development of familial genetic testing.

Oral Antibiotic Bowel Preparation Significantly Reduces Surgical Site Infection Rates and Readmission Rates in Elective Colorectal Surgery.

OBJECTIVE To determine the relationship between oral antibiotic bowel preparation (OABP) and surgical site infection (SSI) rates in a national colectomy cohort. BACKGROUND OABP for elective colorectal surgery has fallen out of favor. Large cohort studies show that OABP is associated with a 50% reduction in SSI after colectomy. METHODS A retrospective analysis of the National Surgical Quality Improvement Program colectomy cohort from 2011 to 2012 was performed to examine the association between use of OABP and outcomes of SSI, length of stay (LOS), and readmission after elective colectomy. Univariate and multivariable analyses for SSI were performed. RESULTS The cohort included 8415 colorectal operations of which 5291 (62.9%) had a minimally invasive surgical (MIS) approach. Overall, 25.6% had no bowel preparation, 44.9% had mechanical bowel preparation (MBP) only, and 29.5% received OABP. The SSI rate was 11.1%, and it varied by preparation type: 14.9% no preparation, 12.0% MBP, and 6.5% OABP (P < 0.001). OABP group had significantly shorter hospital LOS: (median = 4, interquartile range: 3-6) versus other preparations (median LOS = 5) (P < 0.001). Readmission rates were lowest in OABP (8.1%) and highest in the no preparation group (11.8%). Multivariable logistic regressions found OABP associated with lower SSI [adjusted odds ratio (ORadj) = 0.46, 95% confidence interval (CI): 0.36-0.59]. Stratified models found OABP protective for SSI for both open procedures (ORadj = 0.40, 95% CI: 0.30-0.53) and MIS procedures (ORadj = 0.48, 95% CI: 0.36-0.65). CONCLUSIONS OABP is associated with reduced SSI rates, shorter LOS, and fewer readmissions. Adoption of OABP before elective colectomy would reduce SSI without effecting LOS. The practice of MBP alone should be abandoned.

GP41-specific antibody blocks cell-free HIV type 1 transcytosis through human rectal mucosa and model colonic epithelium.

Monostratified epithelial cells translocate HIV type 1 (HIV-1) from the apical to the basolateral surface via vesicular transcytosis. Because acutely transmitted HIV-1 is almost exclusively CCR5-tropic and human intestinal epithelial cells preferentially transcytose CCR5-tropic virus, we established epithelial monolayers using polarized HT-29 cells transduced to express CCR5, and an explant system using normal human rectal mucosa, to characterize biological parameters of epithelial cell transcytosis of HIV-1 and assess antiviral Ab blockade of transcytosis. The amount of cell-free HIV-1 transcytosed through the epithelial monolayer increased linearly in relation to the amount of virus applied to the apical surface, indicating transcytosis efficiency was constant (r2 = 0.9846; p < 0.0001). The efficiency of HIV-1 transcytosis ranged between 0.05 and 1.21%, depending on the virus strain, producer cell type and gp120 V1–V3 loop signature. Inoculation of HIV-1 neutralizing Abs to the immunodominant region (7B2) or the conserved membrane proximal external region (2F5) of gp41 or to cardiolipin (IS4) onto the apical surface of epithelial monolayers prior to inoculation of virus significantly reduced HIV-1 transcytosis. 2F5 was the most potent of these IgG1 Abs. Dimeric IgA and monomeric IgA, but not polymeric IgM, 2F5 Abs also blocked HIV-1 transcytosis across the epithelium and, importantly, across explanted normal human rectal mucosa, with monomeric IgA substantially more potent than dimeric IgA in effecting transcytosis blockade. These findings underscore the potential role of transcytosis blockade in the prevention of HIV-1 transmission across columnar epithelium such as that of the rectum.

Oral antibiotic bowel preparation reduces length of stay and readmissions after colorectal surgery.

BACKGROUND Oral antibiotic bowel preparation (OABP) before colorectal resection has been shown to reduce surgical site infections. We examined whether OABP decreases length of stay (LOS) and readmissions for colorectal surgery. STUDY DESIGN This retrospective study used national Veterans Affairs Surgical Quality Improvement Program preoperative risk and outcomes data linked to Veterans Affairs Administrative and Pharmacy Benefits Management data on patients undergoing elective colorectal resections from 2005 to 2009. Exclusion criteria were preoperative LOS >2 days, American Society of Anesthesiologists class 5, or death before discharge. Patient and surgery characteristics, bowel preparation use, presence of an ostomy, indication for surgery, and indication for readmission using ICD-9 codes were determined. Negative binomial regression was used to model LOS. Logistic regression analyses modeled 30-day readmission. RESULTS Of the 8,180 patients, 1,161 (14.2%) were readmitted within 30 days. Length of stay and readmissions varied significantly by bowel preparation, procedure, presence of an ostomy, and American Society of Anesthesiologists class. Oral antibiotic bowel preparation was associated with a below-median postoperative LOS (negative binomial regression estimate = -0.1159; p < 0.0001) and fewer 30-day readmissions (adjusted odds ratio = 0.81; 95% CI, 0.68-0.97). Overall, 4.9% were readmitted for infections (ICD-9 codes) and this varied by bowel preparation (no preparation 6.1%, mechanical 5.4%, OABP 3.9%; p = 0.001). The readmission rate for noninfectious reasons was 9.3% and did not differ significantly by bowel preparation (no preparation 9.9%, mechanical 9.6%, OABP 8.8%; p = 0.38). CONCLUSIONS Oral antibiotic bowel preparation before elective colorectal surgery is associated with shorter postoperative LOS and lower 30-day readmission rates, primarily due to fewer readmissions for infections. Prospective studies are needed to verify these results.

Extracellular matrix-associated cytokines regulate CD4+ effector T-cell responses in the human intestinal mucosa.

Extracellular matrix (stroma) regulation of mucosal T-cell function is incompletely understood. In this study, we uncovered a role for intestinal stromal products in the innate regulation of effector T cells. Stroma-conditioned media (S-CM) derived from the normal human intestinal stroma (transforming growth factor-β (TGF-β)hi/interleukin (IL)-6lo/IL-1βlo) significantly downregulated T-cell proliferation and interferon-γ (IFN-γ) production compared with S-CM derived from the inflamed Crohns mucosa (TGF-βhi/IL-6hi/IL-1βhi). Antibody neutralization studies showed that TGF-β in normal S-CM inhibited T-cell proliferation and IFN-γ production, whereas IL-6 plus IL-1β in Crohns S-CM promoted T-cell proliferation, and IL-1β alone promoted IFN-γ and IL-17 release. Importantly, normal S-CM inhibited T-bet expression, whereas Crohns S-CM activated signal transducer and activator of transcription 3, suggesting that discordant T-cell responses are regulated at the transcription factor and signaling levels. These findings implicate stromal TGF-β in the downregulation of T-cell 2responses in the normal intestinal mucosa, and stromal IL-6 and IL-1β in the promotion of Th1 and Th17 responses in the inflamed Crohns mucosa, suggesting an innate regulatory function for the intestinal extracellular matrix.

Outcomes of right- compared with left-side colectomy.

Right colon resections are perceived as less morbid than left colon resections. The purpose of this study was to determine the differences in outcomes between right-and left-side colon resections. We reviewed 420 consecutive open colectomies over 4 years. Patient demographics, surgical indications, intraoperative variables, and outcomes were collected. Two hundred twenty-three right colectomies (RCs) were compared with 197 left colectomies (LCs). RCs were more often required for cancer (111 vs 65, P < .001) and LCs for diverticular disease (10 vs 90, P < .001). LCs were more often performed emergently (36% vs 23%, P = .004) and required longer mean operative times (149 minutes vs 130 minutes, P = .004). Complications and mortality in the two groups were equal statistically. In the emergent colectomy subset, LCs were associated with greater intraoperative blood loss (315 vs 201 mL, P = .02) but fewer complications (11% vs 17%, P = .003).

Colorectal Neoplasia and Inflammatory Bowel Disease

Inflammatory bowel disease is associated with an increased risk of gastrointestinal neoplasia. Ulcerative colitis increases the risk of colorectal cancer, and patients with this condition should undergo routine colonoscopic surveillance to detect neoplasia. Crohns disease increases the risk of malignancy in inflamed segments of bowel, which may include small bowel, colon, rectum, and anus.

Biomaterials: so many choices, so little time. What are the differences?

The use of biologic mesh has increased greatly in recent years in response to the need for a solution in managing contaminated hernias. Multiple different meshes are commercially available, and are derived from a variety of sources, including human dermis as well as animal sources. For a mesh to be effective, it must be resistant to infection, have adequate tensile strength for hernia repair, and be well tolerated by the host. To achieve this end, biologic meshes go through an intense processing that varies from one product to the next. In this article, the authors review the types of mesh available, how they are processed, and examine these characteristics in terms of their strengths and weaknesses in application to surgical technique.

Risk of Surgical Site Infection (SSI) following Colorectal Resection Is Higher in Patients With Disseminated Cancer: An NCCN Member Cohort Study

BACKGROUNDSurgical site infections (SSIs) following colorectal surgery (CRS) are among the most common healthcare-associated infections (HAIs). Reduction in colorectal SSI rates is an important goal for surgical quality improvement.OBJECTIVETo examine rates of SSI in patients with and without cancer and to identify potential predictors of SSI risk following CRSDESIGNAmerican College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) data files for 2011-2013 from a sample of 12 National Comprehensive Cancer Network (NCCN) member institutions were combined. Pooled SSI rates for colorectal procedures were calculated and risk was evaluated. The independent importance of potential risk factors was assessed using logistic regression.SETTINGMulticenter studyPARTICIPANTSOf 22 invited NCCN centers, 11 participated (50%). Colorectal procedures were selected by principal procedure current procedural technology (CPT) code. Cancer was defined by International Classification of Disease, Ninth Revision, Clinical Modification (ICD-9-CM) codes.MAIN OUTCOMEThe primary outcome of interest was 30-day SSI rate.RESULTSA total of 652 SSIs (11.06%) were reported among 5,893 CRSs. Risk of SSI was similar for patients with and without cancer. Among CRS patients with underlying cancer, disseminated cancer (SSI rate, 17.5%; odds ratio [OR], 1.66; 95% confidence interval [CI], 1.23-2.26; P=.001), ASA score ≥3 (OR, 1.41; 95% CI, 1.09-1.83; P=.001), chronic obstructive pulmonary disease (COPD; OR, 1.6; 95% CI, 1.06-2.53; P=.02), and longer duration of procedure were associated with development of SSI.CONCLUSIONSPatients with disseminated cancer are at a higher risk for developing SSI. ASA score >3, COPD, and longer duration of surgery predict SSI risk. Disseminated cancer should be further evaluated by the Centers for Disease Control and Prevention (CDC) in generating risk-adjusted outcomes.Infect Control Hosp Epidemiol 2018;39:555-562.