Alice Murray

Combined preoperative mechanical bowel preparation with oral antibiotics significantly reduces surgical site infection, anastomotic leak, and ileus after colorectal surgery.

OBJECTIVES To clarify whether bowel preparation use or its individual components [mechanical bowel preparation (MBP)/oral antibiotics] impact specific outcomes after colorectal surgery. METHODS National Surgical Quality Improvement Program-targeted colectomy data initiated in 2012 capture information on the use/type of bowel preparation and colorectal-specific complications. For patients undergoing elective colorectal resection, the impact of preoperative MBP and antibiotics (MBP+/ABX+), MBP alone (MBP+/ABX-), and no bowel preparation (no-prep) on outcomes, particularly anastomotic leak, surgical site infection (SSI), and ileus, were evaluated using unadjusted/adjusted logistic regression analysis. RESULTS Of 8442 patients, 2296 (27.2%) had no-prep, 3822 (45.3%) MBP+/ABX-, and 2324 (27.5%) MBP+/ABX+. Baseline characteristics were similar; however, there were marginally more patients with prior sepsis, ascites, steroid use, bleeding disorders, and disseminated cancer in no-prep. MBP with or without antibiotics was associated with reduced ileus [MBP+/ABX+: odds ratio (OR) = 0.57, 95% confidence interval (CI): 0.48-0.68; MBP+/ABX-: OR = 0.78, 95% CI: 0.68-0.91] and SSI [MBP+/ABX+: OR = 0.39, 95% CI: 0.32-0.48; MBP+/ABX-: OR = 0.80, 95% CI: 0.69-0.93] versus no-prep. MBP+/ABX+ was also associated with lower anastomotic leak rate than no-prep [OR = 0.45 (95% CI: 0.32-0.64)]. On multivariable analysis, MBP with antibiotics, but not without, was independently associated with reduced anastomotic leak (OR = 0.57, 95% CI: 0.35-0.94), SSI (OR = 0.40, 95% CI: 0.31-0.53), and postoperative ileus (OR = 0.71, 95% CI: 0.56-0.90). CONCLUSIONS These data clarify the near 50-year debate whether bowel preparation improves outcomes after colorectal resection. MBP with oral antibiotics reduces by nearly half, SSI, anastomotic leak, and ileus, the most common and troublesome complications after colorectal surgery.

Risk of Surgical Site Infection Varies Based on Location of Disease and Segment of Colorectal Resection for Cancer

BACKGROUND: Current quality-monitoring initiatives do not accurately evaluate surgical site infections based on type of surgical procedure. OBJECTIVE: This study aimed to characterize the effect of the anatomical site resected (right, left, rectal) on wound complications, including superficial, deep, and organ space surgical site infections, in patients who have cancer. SETTINGS: Data were retrieved from the American College of Surgeons National Surgical Quality Improvement Program database. DESIGN: This study was designed to determine the independent risk associated with the anatomical location of cancer resection for all subtypes of surgical site infection. Statistical methods included the Fisher exact test, the &khgr;2 test, and univariable and multivariable analyses for each outcome of interest. PATIENTS: All colon and rectal resections for colorectal cancer between 2006 and 2012 were selected. Included were 45,956 patients: 17,993 (39.2%) underwent right colectomy, 11,538 (25.1%) underwent left colectomy, and 16,425 (35.7%) underwent rectal resections. RESULTS: The overall surgical site infection rate was 12.3%: 3.7% organ space, 1.4% deep, and 7.2% superficial. On multivariable analysis, rectal resection was associated with the greatest odds of overall surgical site infections in comparison with left- or right-sided resections (rectal OR, 1.51; 95% CI, 1.35–1.69 vs left OR, 1.09; 95% CI, 0.97–1.23 vs right OR, 1). Rectal resections were also associated with greater odds of developing a deep surgical site infection than either right (rectal OR, 1.45; 95% CI, 1.06–1.99) or left (OR, 0.89; 95% CI, 0.62–1.27). The likelihood of organ space surgical site infection followed a similar pattern (rectal OR, 1.83; 95% CI 1.49–2.25; left colon, OR, 0.95; 95% CI, 0.75–1.19). Rectal and left resections had increased odds of superficial surgical site infections compared with right resections (rectal OR, 1.31; 95% CI, 1.14–1.51; left OR, 1.19; 95% CI, 1.03–1.37). LIMITATIONS: This is a retrospective observational study. CONCLUSIONS: Rectal resections for cancer are independently associated with an increased likelihood of superficial, deep, and organ space infections. The policy on surgical site infections as a quality measure currently in place requires modification to adjust for the location of pathology and, hence, the anatomical segment resected when assessing the risk for type of surgical site infection.

Bowel Preparation: Are Antibiotics Necessary for Colorectal Surgery?

The goal of bowel preparation is to facilitate safe surgery and reduce postoperative complications. The use of antibiotic prophylaxis in colorectal surgery is essential, not controversial. Historical evidence supports the use of oral antibiotics in combination with mechanical cleansing for the reduction of infectious complications. Prophylactic intravenous antibiotic administration at induction in cleancontaminated surgery is now both routine and mandatory. Oral and intravenous antibiotics with mechanical bowel preparation show improved colectomy-specific outcomes compared with no preparation or mechanical bowel preparation plus intravenous antibiotics alone.

PWE-265 Laparoscopic versus open colectomy: which technique to use and when?

Introduction While the role of laparoscopic surgery (LC) for colorectal cancer (CRC) has evolved for use in the majority of instances, the ability to predict circumstances where it is associated with better or worse outcomes after colectomy will help guide surgeons in the relative choice of the procedure over open surgery (OC) particularly when dealing with patients expected to be at high risk for postoperative complications. This study examines factors that may guide the relative circumstances where either the laparoscopic approach may preferably be indicated or avoided. Method The National Surgical Quality Improvement Program 2012–2013 database was used to identify patients who underwent LC and OC for the treatment of CRC. First, the 2 surgical groups were compared using Mann Whitney U tests and Chi-square statistics. Next, the relationship between surgery type (LC vs. OC) and postoperative outcomes, classified as either medical or surgical complications, was examined using multivariable logistic models. Any covariates univariately associated with the outcome of interest (Pvalue <0.20) were controlled for in the multivariable model. Lastly, the interaction between each of these covariates and LC/OC was examined to identify risk factors that may make LC or OC more preferable. Results Of the 24502 patients who underwent surgery for CRC, 11866 (48.4%) underwent LC and 12636 (51.6%) underwent OC. There were significant differences in comorbidities between patients who underwent LC versus OC, with mean BMI, chronic steroid use and neurological disease as the only exceptions. OC patients were more likely to undergo emergency surgery, have ASA class 3/4 instead of ASA 1/2 and undergo proctectomy over colectomy than LC patients. Patients undergoing LC had a lower likelihood of developing any complication compared to OC. When evaluating factors associated with the occurrence of surgical complications, ASA class was the only common independent predictor (Pvalue 0.02). LC was associated with lower complication rates for both ASA class 1/2 and 3/4 patients and was even found to be more protective for class 3/4 (OR 0.52 vs. 0.72). When evaluating the relative benefit of LC over OC concerning medical complications, neurological disease remained the only independent predictor (Pvalue 0.02). Hence, patients with a history of neurological disease undergoing LC were more likely to develop medical complications (OR 1.3) compared to those without a neurological history (OR 0.57). Conclusion These data suggest that while OC is currently the preferred technique for patients with comorbid conditions, LC confers particular benefits in terms of surgical complications in CRC patients with the most significant comorbid conditions. Disclosure of interest None Declared.

Su1740 30-Day Mortality After Emergency Surgery for Colorectal Cancer: Who Is At Risk?

Introduction: Peritoneal carcinomatosis denotes extensive tumour involvement of the peritoneum, and is often regarded as terminal. There has been a paradigm shift in treatment, with the application of cytoreductive surgery combined with intra-peritoneal chemotherapy. The extensive nature of the surgery and malignancy-associated hypercoagulable state should increase the risk of PE, which can further increase morbidity and/or mortality. Incidence and risk factors for pulmonary embolism (PE) in this population have not been investigated in detail. Aims: To establish the incidence and specific operative risk factors for developing PE in patients with peritoneal carcinomatosis post peritonectomy and peri-operative intraperitoneal chemotherapy. Methods: A cohort of 596 patients that underwent cytoreductive surgery (peritonectomy) over a 12-year period was identified using the prospective database from St George Hospital Peritonectomy Unit. A case-control study was undertaken whereby cases were defined by the development of PE within 60 days of peritonectomy. A diagnosis of PE was based on computed tomography pulmonary angiography confirmation. The prospective database was reviewed to obtain the following clinical information for both cases (with PE) and controls (without PE): length of surgery, use of hyperthermic intraperitoneal chemotherapy (HIPEC) and early postoperative intraperitoneal chemotherapy (EPIC), peritoneal carcinomatosis index (PCI) and number of intraoperative blood transfusions. Results: The mean age of the cohort was 52.7 ± 13.1 years, with no significant difference in the ages of cases or controls; 43.3% were male and 56.7% were female. Primary malignancies in these patients were pseudomyxoma peritonei, appendiceal, ovarian or colorectal cancer, and mesothelioma. Out of the 596 patient cohort, 34 were identified as having PE post cytoreductive surgery (5.7%). When compared to controls, the PE group had longer mean operative time of 10.4 ± 2.8 hours vs 8.9 ± 3.1 hours (p=0.01) and higher mean PCI values at 23 ± 12 vs 18 ± 11 (p=0.02). An operative time of more >9 hours increased the risk of developing PE (OR 3.3, 95% CI 1.41-7.72, p=0.006) as did having a PCI of >20 (OR 2.4, 95% CI 1.18-4.9, p=0.02). There was no difference in mean transfusion requirements (6.6 vs 6.0; p=0.67). No significant association was found between HIPEC and development of PE (x2=2.87, 1 df, P=0.9) or EPIC and subsequent PE (x2=0.001, 1 df, P=1). Conclusions: There is a relatively high incidence of pulmonary embolism in patients following cytoreductive surgery for peritoneal carcinomatosis. Patients at highest risk of developing PE postoperatively are those with PCI of more than 20 and those who have operations lasting more than 9 hours. Peri-operative chemotherapy and blood transfusions are not risk factors for PE.