Daniel I. Chu

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.

Molecular characterization of Ancylostoma ceylanicum Kunitz-type serine protease inhibitor: evidence for a role in hookworm-associated growth delay.

ABSTRACT Hookworm infection is a major cause of iron deficiency anemia and malnutrition in developing countries. The Ancylostoma ceylanicum Kunitz-type inhibitor (AceKI) is a 7.9-kDa broad-spectrum inhibitor of trypsin, chymotrypsin, and pancreatic elastase that has previously been isolated from adult hookworms. Site-directed mutagenesis of the predicted P1 inhibitory reactive site amino acid confirmed the role of Met26 in mediating inhibition of the three target serine proteases. By using reverse transcription-PCR, it was demonstrated that the level of AceKI gene expression increased following activation of third-stage larvae with serum and that the highest level of expression was reached in the adult stage of the parasite. Immunohistochemistry studies performed with polyclonal immunoglobulin G raised against recombinant AceKI showed that the inhibitor localized to the subcuticle of the adult hookworm, suggesting that it has a potential in vivo role in neutralizing intestinal proteases at the surface of the parasite. Immunization with recombinant AceKI was shown to confer partial protection against hookworm-associated growth delay without a measurable effect on anemia. Taken together, the data suggest that AceKI plays a role in the pathogenesis of hookworm-associated malnutrition and growth delay, perhaps through inhibition of nutrient absorption in infected hosts.

N-acetyl-l-cysteine decreases intra-abdominal adhesion formation through the upregulation of peritoneal fibrinolytic activity and antioxidant defenses.

BACKGROUND Intraperitoneal adhesions occur in more than 94% of patients after abdominal surgery. Mechanisms that decrease oxidative stress and upregulate peritoneal fibrinolysis reduce adhesions. N-acetyl-l-cysteine (NAC) is a clinically relevant antioxidant whose effect on peritoneal fibrinolysis and ability to decrease adhesions has not been established. The aims of this study were to determine if NAC reduces adhesions and to characterize its potential mechanism(s) of action. METHODS Male Wistar rats (n = 92) received 0.9% saline (OP Control), intraperitoneal NAC (150 mg/kg, OP + NAC), or oral NAC (1200 mg/kg) twice daily on preoperative day 1, day of operation, and postoperative day 1. Adhesions were induced on the day of operation using our previously described ischemic button model. Animals were killed on postoperative day 7 for adhesion scoring. Peritoneal tissue and fluid from the intraperitoneal NAC group were measured at 24 hours for fibrinolytic activity, tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1), total glutathione, and 8-isoprostane (8-IP). The effect of NAC on tPA and PAI-1 production was tested in vitro in human mesothelial cells. The effect of NAC on intestinal wound healing was measured using colonic anastomotic burst pressures. RESULTS Intraperitoneal NAC reduced adhesions by 53% (P < .001) compared to OP Controls without affecting anastomotic wound healing. NAC increased the tPA/PAI-1 protein ratio and peritoneal fibrinolytic activity by 69% and 127%, respectively, compared to OP Controls (P < .05). NAC did not restore total glutathione levels in peritoneal adhesion tissue but decreased 8-IP by 46% and 65% (P < .05) in peritoneal tissue and fluid, respectively, compared to OP Controls. Human mesothelial cells incubated with NAC exhibited a concentration-dependent increase in the tPA/PAI-1 ratio, which supported in vivo observations (P < .05). Oral NAC did not decrease adhesions. CONCLUSION NAC administered intraperitoneally decreased adhesion formation while upregulating peritoneal fibrinolytic activity and antioxidant defenses without affecting normal anastomotic wound healing. These data suggest a potential new therapeutic use for NAC in adhesion prevention.

Strategy for the difficult-to-reach ileal pouch-anal anastomosis: technical steps of an in vivo application of a mesenteric-lengthening technique.

Proctocolectomy (PC) with ileal pouch-anal anastomosis (IPAA) is the procedure of choice in patients with familial adenomatous polyposis (FAP) and chronic ulcerative colitis (CUC) who need surgery. Construction of an IPAA can be technically difficult in some cases due to a short ileal mesentery. We report a case of a 19-year-old male with FAP who underwent PC and IPAA as the first part of a twostage procedure. On initial intraoperative evaluation, the patient had a significantly foreshortened ileal mesentery that limited the reach into the pelvis for a tension-free anastomosis. We present a technical modification to deal with this challenging scenario that can avoid having to proceed with a permanent ileostomy. This mesentericlengthening technique is not well described in the clinical setting. Therefore, this report serves to (1) provide detailed step-by-step in vivo instructions, (2) visually demonstrate the technique, and (3) establish this technique in the framework of current strategies to provide reach during IPAA. Methods

Rates of hospitalization among African American and Caucasian American patients with Crohn's disease seen at a tertiary care center

Abstract Background There is equivocal evidence regarding differences in the clinical course and outcomes of Crohn’s disease (CD) among African Americans compared with Caucasian Americans. We sought to analyze whether African Americans with CD are more likely to be hospitalized for CD-related complications when compared with Caucasian Americans with CD. Methods We conducted a retrospective cohort study including 909 African Americans and Caucasian Americans with CD who were seen at our tertiary care Inflammatory Bowel Disease (IBD) referral center between 2000 and 2013. We calculated the rate of hospitalization for CD-related complications among African Americans and Caucasian Americans separately. Zero-inflated Poisson regression models with robust variance estimates were used to estimate crude and multivariable adjusted rate ratios (RR) for CD-related hospitalizations. Multivariable adjusted models included adjustment for age, sex, duration of CD, smoking and CD therapy. Results The cumulative rate of CD-related hospital admissions was higher among African American patients compared with Caucasian American patients (395.6/1000 person-years in African Americans vs. 230.4/1000 person-years in Caucasian Americans). Unadjusted and multivariable adjusted rate ratios for CD-related hospitalization comparing African Americans and Caucasian Americans were 1.59 (95% confidence interval [95%CI]: 1.10–2.29; P=0.01) and 1.44 (95%CI: 1.02–2.03; P=0.04), respectively. Conclusions African Americans with CD followed at a tertiary IBD-referral center had a higher rate for CD-related hospitalizations compared with Caucasian Americans. Future studies should examine whether socioeconomic status and biologic markers of disease status could explain the higher risk observed among African Americans.

Local repair of stoma prolapse: Case report of an in vivo application of linear stapler devices

Introduction One of the most common late complications following stoma construction is prolapse. Although the majority of prolapse can be managed conservatively, surgical revision is required with incarceration/strangulation and in certain cases laparotomy and/or stoma reversal are not appropriate. This report will inform surgeons on safe and effective approaches to revising prolapsed stomas using local techniques. Presentation of case A 58 year old female with an obstructing rectal cancer previously received a diverting transverse loop colostomy. On completion of neoadjuvant treatment, re-staging found new lung metastases. She was scheduled for further chemotherapy but incarcerated a prolapsed segment of her loop colostomy. As there was no plan to resect her primary rectal tumor at the time, a local revision was preferred. Linear staplers were applied to the prolapsed stoma in step-wise fashion to locally revise the incarcerated prolapse. Post-operative recovery was satisfactory with no complications or recurrence of prolapse. Discussion We detail in step-wise fashion a technique using linear stapler devices that can be used to locally revise prolapsed stoma segments and therefore avoid a laparotomy. The procedure is technically easy to perform with satisfactory post-operative outcomes. We additionally review all previous reports of local repairs and show the evolution of local prolapse repair to the currently reported technique. Conclusion This report offers surgeons an alternative, efficient and effective option for addressing the complications of stoma prolapse. While future studies are needed to assess long-term outcomes, in the short-term, our report confirms the safety and effectiveness of this local technique.

Imaging for Inflammatory Bowel Disease

Multiple imaging modalities exist for inflammatory bowel disease. This article explores the use of plain radiographs, contrast radiologic imaging, computed tomography, MRI, ultrasound, and capsule endoscopy. History, technique, indications for use, limitations, and future directions are discussed for each modality.

The Association for Academic Surgeons 2001-2010: a decade of inclusiveness

The Association for Academic Surgery (AAS) was established to inspire and develop academic surgeons. Since its founding in 1966, each decade has been marked by continued growth and innovations. The era of 2001-2010 was a decade notable for its focus on inclusiveness and diversity. In those ten years, the AAS grew its membership from all surgical backgrounds, established defining programs that remain today, and invested substantially in international outreach. In this article, we review these historical highlights and will demonstrate that the AAS remains the most important home for the young academic surgeon.

A “Solution” to the Application of an Effective Physical Barrier for the Prevention of Intra-abdominal Adhesions

We are pleased to comment on the research by Greenawalt et al. [1] that validates the application of an effective solution derived from the solid physical barrier, Seprafilm, for the prevention of abdominal adhesions. The goal of their research was to continue the effort to thwart our age-old nemesis, the intra-abdominal adhesion, which remains perhaps the most significant, long-term postoperative sequelae of abdominal surgery [2]. Many studies, including our own [3], have reported that up to 94% of patients develop intra-abdominal adhesions following laparotomy. Abdominal adhesions are associated with a range of complications, including difficult and dangerous reoperation, infertility, chronic abdominal and pelvic pain, and small bowel obstruction. These adhesion-related complications pose a tremendous burden for the U.S. health care system with most recent estimates at over

Enhanced Recovery After Surgery and Surgical Disparities

5 billion dollars annually [4]. Since the dawn of surgery, surgeons who delved into the abdomen have had to contend with the inevitable and morbid consequences associated with abdominal adhesions. Surprisingly, the Babylonians and ancient Egyptians first described adhesions more than 1,500 years ago [5]; however, it was not until the widespread use of anesthesia in the mid-1800s that more invasive abdominal procedures became more prevalent and the extent of the problems caused by intra-abdominal adhesions was truly realized. This led to the first concerted efforts at adhesion prevention in the late 1800s when published reports of the use of various adjuvants and mechanical separation methods began to appear in the surgical literature. For the next century, scientific and anecdotal reports chronicled hundreds of accounts to prevent adhesions, most with only a modicum of success. Our point in describing these historical events is to emphasize that we have known about adhesions for a very long time, and despite centuries of surgical experience, techniques to prevent adhesions are still very rudimentary with the primary emphasis on practicing the surgical principles of adhesion prevention: gentle handling of tissues, meticulous control of bleeding, avoidance of foreign materials, excision of necrotic tissue, minimization of ischemia, and desiccation and prevention of infection. Nonetheless, adhesions continue to occur with high incidence and adhesion-related complications are on the rise. More recent research over the last 2 decades has culminated in the development of an efficacious physical barrier to prevent adhesion formation, the FDA-approved hyaluronic acid/carboxymethylcellulose bioresorbable membrane (HA/CMC) or Seprafilm [6]. These solid sheet-like devices