Anand G. Menon

Emergency Laparoscopic Sigmoidectomy for Perforated Diverticulitis with Generalised Peritonitis: A Systematic Review

Background: Laparoscopic sigmoidectomy for diverticulitis has initially been confined to the elective setting. However, open acute sigmoidectomy for perforated diverticulitis is associated with high morbidity rates that might be reduced after laparoscopic surgery. The aim of this systematic review was to assess the feasibility of emergency laparoscopic sigmoidectomy for perforated diverticulitis. Methods: We performed a systematic search of PubMed, EMBASE and CENTRAL. All studies reporting on patients with perforated diverticulitis (Hinchey III-IV) treated by laparoscopic sigmoidectomy in the acute phase were included, regardless of design. Results: We included 4 case series and one cohort study (total of 104 patients) out of 1,706 references. Hartmanns procedure (HP) was performed in 84 patients and primary anastomosis in 20. The mean operating time varied between 115 and 200 min. The conversion rate varied from 0 to 19%. The mean length of hospital stay ranged between 6 and 16 days. Surgical re-intervention was necessary in 2 patients. In 20 patients operated upon without defunctioning ileostomy, no anastomotic leakage was reported. Three patients died during the postoperative period. Stoma reversal after HP was performed in 60 out of 79 evaluable patients (76%). Conclusions: Acute laparoscopic sigmoidectomy for the treatment of perforated diverticulitis is feasible in selected patients provided they are handled by experienced hands.

Clinical Endpoint, Early Detection, and Differential Diagnosis of Postoperative Ileus: A Systematic Review of the Literature

Background: This systematic review summarizes evidence regarding clinical endpoints, early detection, and differential diagnosis of postoperative ileus (POI). Methods: Using MEDLINE, EMBASE, Cochrane, and Web-of-Science, we identified 2,084 articles. Risk of bias and level of evidence (LOE) of the included articles were determined, and relevant results were summarized. Results: Eleven articles were included, most of which with substantial risks of bias. Bowel motility studies revealed that defecation together with solid food tolerance is the most representative clinical endpoint of POI (LOE: 2b); other clinical signs (e.g. bowel sounds, passage of flatus) did not correlate with a full recovery of bowel motility. Inflammatory parameters including interleukin (IL)-6, IL-1, and TNF-α might assist in an early detection of prolonged POI (LOE: 4). Clinical manifestations (e.g. nausea, vomiting, abdominal distension, bowel sounds, flatus) and X-ray examinations provided limited aid to the differential diagnosis of POI, while CT with Gastrografin had the best specificity and sensitivity (both 100%; LOE: 1c). Conclusions: Postoperative defecation together with tolerance of solid food intake seems to be the best clinical endpoint of POI. CT has the best differential diagnostic value between POI and other complications. Prospective studies with a high LOE are in great need.

Cytokines as early markers of colorectal anastomotic leakage: A systematic review and meta-analysis

Purpose. Colorectal anastomotic leakage (CAL) is one of the most severe complications after colorectal surgery. This meta-analysis evaluates whether systemic or peritoneal inflammatory cytokines may contribute to early detection of CAL. Methods. Systematic literature search was performed in the acknowledged medical databases according to the PRISMA guidelines to identify studies evaluating systemic and peritoneal levels of TNF, IL-1β, IL-6, and IL-10 for early detection of CAL. Means and standard deviations of systemic and peritoneal cytokine levels were extracted, respectively, for patients with and without CAL. The meta-analysis of the mean differences was carried out for each postoperative day using Review Manager. Results. Seven articles were included. The meta-analysis was performed with 5 articles evaluating peritoneal cytokine levels. Peritoneal levels of IL-6 were significantly higher in patients with CAL compared to patients without CAL on postoperative days 1, 2, and 3 (P < 0.05). Similar results were found for peritoneal levels of TNF but on postoperative days 3, 4, and 5 (P < 0.05). The articles regarding systemic cytokine levels did not report any significant difference accordingly. Conclusion. Increased postoperative levels of peritoneal IL-6 and TNF are significantly associated with CAL and may contribute to its early detection.

Incidence, risk factors and prevention of stoma site incisional hernias: a systematic review and meta-analysis

Stoma reversal might lead to a stoma site incisional hernia. Recently, prophylactic mesh reinforcement of the stoma site has gained increased attention, supporting the need for accurate data on the incidence of and risk factors for stoma site incisional hernia and to identify high‐risk patients. The aim of this study was to assess incidence, risk factors and prevention of stoma site incisional hernias.

Oxygen therapies and their effects on wound healing

Oxygen is an important factor for wound healing. Although several different therapies investigated the use of oxygen to aid wound healing, the results of these studies are not unequivocal. This systematic review summarizes the clinical and experimental studies regarding different oxygen therapies for promoting wound healing, and evaluates the outcomes according the methodological details. A systematic literature search was conducted using Embase, Medline, Web of Science, Cochrane, PubMed publisher, and Google Scholar libraries. Clinical and experimental studies investigating oxygen for wound healing were selected. Included articles were categorized according to the kind of therapy, study design, and wound type. The methodological details were extracted and analyzed. Sixty‐five articles were identified and divided in three different oxygen therapies: Local oxygen therapy, hyperbaric oxygen therapy, and supplemental inspired oxygen therapy. More than half of the included local oxygen and hyperbaric oxygen studies had one or more significant positive outcomes, 77 and 63%, respectively. Supplemental inspired oxygen therapy during gastrointestinal and vascular surgery was more likely to have a positive result than during other surgical interventions reducing surgical site infections. These many positive outcomes promote the use of oxygen treatment in the stimulation of wound healing. However, the lack of clinical studies and vast methodological diversity made it impossible to perform a proper comparison within and between the different therapies. Further randomized clinical studies are warranted to examine the value of these therapies, especially studies that investigate the more patient‐friendly oxygen dressings and topical wound oxygen therapies. Also, to achieve more solid and consistent data, studies should use more standardized methods and subjects.

Postoperative Hemodynamic Index Measurement With Miniaturized Dynamic Light Scattering Predicts Colorectal Anastomotic Healing.

Introduction. Perioperative bowel perfusion (local hemodynamic index [LHI]) was measured with a miniaturized dynamic light scattering (mDLS) device, aiming to determine whether anastomotic perfusion correlates with the anastomotic healing process and whether LHI measurement assists in the detection of anastomotic leakage (AL) in colorectal surgery. Methods. A partial colectomy was performed in 21 male Wistar rats. Colonic and anastomotic LHIs were recorded during operation. On postoperative day (POD) 3, the rats were examined for AL manifestations. Anastomotic LHI was recorded before determining the anastomotic bursting pressure (ABP). The postoperative LHI measurements were repeated in 15 other rats with experimental colitis. Clinical manifestations and anastomotic LHI were also determined on POD3. Diagnostic value of LHI measurement was analyzed with the combined data from both experiments. Results. Intraoperative LHI measurement showed no correlation with the ABP on POD3. Postoperative anastomotic LHI on POD3 was significantly correlated with ABP in the normal rats (R2 = 0.52; P < .001) and in the rats with colitis (R2 = 0.63; P = .0012). Anastomotic LHI on POD3 had high accuracy for identifying ABP <50 mm Hg (Area under the curve = 0.86; standard error = 0.065; P < .001). A cutoff point of 1236 yielded a sensitivity of 100% and a specificity of 65%. On POD3, rats with LHIs <1236 had significantly higher dehiscence rates (40% vs 0%), more weight loss, higher abscess severity, and lower ABPs (P < .05); worse anastomotic inflammation and collagen deposition were also found in the histological examination. Conclusion. Our data suggest that postoperative evaluation of anastomotic microcirculation with the mDLS device assists in the detection of AL in colorectal surgery.

With routine air leak testing of low colorectal anastomosis is routine intra-operative flexible sigmoidoscopy necessary?

Dear Editor, We read with interest the study from Kamal et al. [1] entitled ‘Should anastomotic assessment with flexible sigmoidoscopy be routine following laparoscopic restorative left colorectal resection?’. They reporteded promising results regarding the prevention of anastomotic leakage (AL) during intraoperative flexible sigmoidoscopy (IOFS). The authors should be congratulated on their very low leak rate of 2.1%, lower than in many studies [2]. Intra-operative flexible sigmoidoscopy may indeed play a major part in such success, but to confirm the authors’ conclusion it would be interesting to know what the leak rate was in patients not having IOFS. Retrospective data from the same centre or from others using a similar approach are necessary to determine the value of IOFS. Despite the success in achieving a low rate of AL, it seems that the air test itself had already predicted most of the cases of leakage identified by IOFS (15/17). Similarly low AL rates have been reported in most studies using the intra-operative air test [3,4], and thus it is unclear whether IOFS is superior in reducing the incidence of anastomotic leakage. Two studies have previously compared the routine and selected application of IOFS, and both reported no distinct advantage for routine application [5,6]. It has been suggested that selected IOFS is indicated under the following circumstances: difficulty in indentifying the location of the tumour, uncertainty regarding distal margin clearance, doubt about anastomotic integrity and a positive air test or rectal bleeding [5]. Combining the data from Kamal et al. with the previous literature it seems that the routine application of the air test with the implementation of IOFS in selected cases may yield a similar medical outcome, probably with at lower cost compared with the routine application of IOFS.

Blockade of LAG3 enhances responses of tumor-infiltrating T cells in mismatch repair-proficient liver metastases of colorectal cancer

ABSTRACT Purpose: Liver metastasis develops in >50% of patients with colorectal cancer (CRC), and is a leading cause of CRC-related mortality. We aimed to identify which inhibitory immune checkpoint pathways can be targeted to enhance functionality of intra-tumoral T-cells in mismatch repair-proficient liver metastases of colorectal cancer (LM-CRC). Methodology: Intra-tumoral expression of multiple inhibitory molecules was compared among mismatch repair-proficient LM-CRC, peritoneal metastases of colorectal cancer (PM-CRC) and primary CRC. Expression of inhibitory molecules was also analyzed on leukocytes isolated from paired resected metastatic liver tumors, tumor-free liver tissues, and blood of patients with mismatch repair-proficient LM-CRC. The effects of blocking inhibitory pathways on tumor-infiltrating T-cell responses were studied in ex vivo functional assays. Results: Mismatch repair-proficient LM-CRC showed higher expression of inhibitory receptors on intra-tumoral T-cells and contained higher proportions of CD8+ T-cells, dendritic cells and monocytes than mismatch repair-proficient primary CRC and/or PM-CRC. Inhibitory receptors LAG3, PD-1, TIM3 and CTLA4 were higher expressed on CD8+ T-cells, CD4+ T-helper and/or regulatory T-cells in LM-CRC tumors compared with tumor-free liver and blood. Antibody blockade of LAG3 or PD-L1 increased proliferation and effector cytokine production of intra-tumoral T-cells isolated from LM-CRC in response to both polyclonal and autologous tumor-specific stimulations. Higher LAG3 expression on intra-tumoral CD8+ T-cells associated with longer progression-free survival of LM-CRC patients. Conclusion: Mismatch repair-proficient LM-CRC may be more sensitive to immune checkpoint inhibitors than mismatch repair-proficient primary CRC. Blocking LAG3 enhances tumor-infiltrating T-cell responses of mismatch repair-proficient LM-CRC, and therefore may be a new promising immunotherapeutic target for LM-CRC.

The effect of age on anastomotic leakage in colorectal cancer surgery: A population-based study

The aim of this study was to investigate the effect of age on CAL and its associated mortality.

Severity of Diverticulitis Does Not Influence Abdominal Complaints during Long-Term Follow-Up

Background: Diverticulitis can lead to localized or generalized peritonitis and consequently induce abdominal adhesion formation. If adhesions would lead to abdominal complaints, it might be expected that these would be more prominent after operation for perforated diverticulitis with peritonitis than after elective sigmoid resection. Aims: The primary outcome of the study was the incidence of abdominal complaints in the long-term after acute and elective surgery for diverticulitis. Methods: During the period 2003 through 2009, 269 patients were operated for diverticular disease. Two hundred eight of them were invited to fill out a questionnaire composed of the gastrointestinal quality of life index and additional questions and finally 109 were suitable for analysis with a mean follow-up of 7.5 years. Results: Analysis did not reveal any significant differences in the incidence of abdominal complaints or other parameters. Conclusion: This retrospective study on patients after operation for diverticulitis shows that in the long term, the severity of the abdominal complaints is influenced neither by the stage of the disease nor by the fact of whether it was performed in an acute or elective setting.