The incidence of extraction site incisional hernia after minimally invasive colorectal surgery: a systematic review and meta-analysis.

AIM: Minimally invasive colorectal surgery reduces surgical trauma with better preservation of abdominal wall integrity, but the extraction site is still at risk of incisional hernia (IH). The aim of this study was to determine pooled incidence of IH for each type of extraction site and to compare rates of IH after midline, nonmidline and Pfannenstiel extraction. METHOD: A systematic review and meta-analysis was conducted using the PRISMA guidelines. Single-armed and multiple-armed cohort studies and randomized controlled trials regarding minimally invasive colorectal surgery were searched from five databases. Outcomes were pooled and compared with random-effects, inverse-variance models. Risk of bias within the studies was assessed using the Cochrane ROBINS-I and RoB 2 tool. RESULTS: Thirty six studies were included, with a total 11,788 patients. The pooled extraction site IH rate was 16.0% for midline (n = 4081), 9.3% for umbilical (n = 2425), 5.2% for transverse (n = 3213), 9.4% for paramedian (n = 134) and 2.1% for Pfannenstiel (n = 1449). Nonmidline extraction (transverse and paramedian) showed significantly lower odds ratios (ORs) for IH when compared with midline extraction (including umbilical). Pfannenstiel extraction resulted in a significantly lower OR for IH compared with midline [OR 0.12 (0.50-0.30)], transverse [OR 0.25 (0.13-0.50)] and umbilical (OR 0.072 [0.033-0.16]) extraction sites. The risks of surgical site infection, seroma/haematoma or wound dehiscence were not significantly different in any of the analyses. CONCLUSION: Pfannenstiel extraction is the preferred method in minimally invasive colorectal surgery. In cases where Pfannenstiel extraction is not possible, surgeons should avoid specimen extraction in the midline.

A comparison between real-time intraoperative voice dictation and the operative report in laparoscopic cholecystectomy: a multicenter prospective observational study.

PURPOSE: The current operative report often inadequately reflects events occurring during laparoscopic cholecystectomy (LC). The addition of intraoperative video recording to the operative report has already proven to add important information. It was hypothesized that real-time intraoperative voice dictation (RIVD) can provide an equal or more complete overview of the operative procedure compared to the narrative operative report (NR) produced postoperatively. METHODS: SONAR is a multicenter prospective observational trial, conducted at four surgical centers in the Netherlands. Elective LCs of patients aged 18 years and older were included. Participating surgeons were requested to dictate the essential steps of LC during surgery. RIVDs and NRs were reviewed according to the stepwise LC guideline of the Dutch Society for Surgery. The cumulative adequacy rates for RIVDs were compared with those of the postoperatively written NR. RESULTS: 79 of 90 cases were eligible for inclusion and available for further analysis. RIVD resulted in a significantly higher adequacy rate compared to NR for the circumferential dissection of the cystic duct and artery (NR 32.5% vs. RIVD 61.0%, P = 0.016). NR had higher adequacy rates in reporting the transection of the cystic duct (NR 100% vs. RIVD 77.9%, P = < 0.001) and the removal of the gallbladder from the liver bed (NR 98.7% vs. RIVD 68.8%, P < 0.001). The total adequacy was not significantly different between the two reporting methods (NR 78.0% vs. RIVD 76.4%, P = 1.00). CONCLUSION: Overall, the adequacy of RIVD is comparable to the postoperatively written NR in reporting surgical steps in LC. However, the most essential surgical step, the circumferential dissection of the cystic duct and artery, was reported more adequately in RIVD.

Favorable Outcomes After Retro-Rectus (Rives-Stoppa) Mesh Repair as Treatment for Noncomplex Ventral Abdominal Wall Hernia, a Systematic Review and Meta-analysis.

OBJECTIVE: To assess prevalence of hernia recurrence, surgical site infection (SSI), seroma, serious complications, and mortality after retro-rectus repair. SUMMARY BACKGROUND DATA: Ventral abdominal wall hernia is a common problem, tied to increasing frailty and obesity of patients undergoing surgery. For noncomplex ventral hernia, retro-rectus (Rives-Stoppa) repair is considered the gold standard treatment. Level-1 evidence confirming this presumed superiority is lacking. METHODS: Five databases were searched for studies reporting on retro-rectus repair. Single-armed and comparative randomized and non-randomized studies were included. Outcomes were pooled with mixed-effects, inverse variance or random-effects models. RESULTS: Ninety-three studies representing 12,440 patients undergoing retro-rectus repair were included. Pooled hernia recurrence was estimated at 3.2% [95% confidence interval (CI): 2.2%-4.2%, n = 11,049] after minimally 12months and 4.1%, (95%CI: 2.9%-5.5%, n = 3830) after minimally 24 months. Incidences of SSI and seroma were estimated at respectively 5.2% (95%CI: 4.2%-6.4%, n = 4891) and 5.5% (95%CI: 4.4%-6.8%, n = 3650). Retro-rectus repair was associated with lower recurrence rates compared to onlay repair [odds ratios (OR): 0.27, 95%CI: 0.15-0.51, P < 0.001] and equal recurrence rates compared to intraperitoneal onlay mesh (IPOM) repair (OR: 0.92, 95%CI: 0.75-1.12, P = 0.400). Retro-rectus repair was associated with more SSI than IPOM repair (OR: 1.8, 95%CI: 1.03 -3.14, P = 0.038). Minimally invasive retro-rectus repair displayed low rates of recurrence (1.3%, 95%CI: 0.7%-2.3%, n = 849) and SSI (1.5%, 95%CI: 0.8%-2.8%, n = 982), albeit based on non-randomized studies. CONCLUSIONS: Retro-rectus (Rives-Stoppa) repair results in excellent outcomes, superior or similar to other techniques for all outcomes except SSI. The latter rarely occurred, yet less frequently after IPOM repair, which is usually performed by laparoscopy.

C-reactive protein (CRP) trajectory as a predictor of anastomotic leakage after rectal cancer resection: A multicentre cohort study.

AIM: This study aimed to identify whether CRP-trajectory measurement, including increase in CRP-level of 50 mg/l per day, is an accurate predictor of anastomotic leakage (AL) in patients undergoing resection for rectal cancer. METHODS: A prospective multicentre database was used. CRP was recorded on the first three postoperative days. Sensitivity, specificity, positive and negative predictive values, and area under the receiver operator characteristic (ROC) curve were used to analyse performances of CRP-trajectory measurements between postoperative day (POD) 1-2, 2-3, 1-3 and between any two days. RESULTS: A total of 271 patients were included in the study. AL was observed in 12.5% (34/271). Increase in CRP-level of 50 mg/l between POD 1-2 had a negative predictive value of 0.92, specificity of 0.71 and sensitivity of 0.57. Changes in CRP-levels between POD 2-3 were associated with a negative predictive value, specificity and sensitivity of 0.89, 0.93 and 0.26, respectively. Changes in CRP-levels between POD 1-3 showed a negative predictive value of 0.94, specificity of 0.76 and sensitivity of 0.65. In addition, 50 mg/l changes between any two days showed a negative predictive value of 0.92, specificity of 0.66 and sensitivity of 0.62. The area under the ROC curve for all CRP-trajectory measurements ranged from 0.593-0.700. CONCLUSION: The present study showed that CRP-trajectory between postoperative days lacks predictive value to singularly rule out AL. Early and safe discharge in patients undergoing rectal surgery for adenocarcinoma cannot be guaranteed based on this parameter. High negative predictive values are mainly caused by the relatively low prevalence of AL.

Matrix metalloproteinase-9 in relation to patients with complications after colorectal surgery: a systematic review.

PURPOSE: Anastomotic leakage (AL) is the most severe complication following colorectal resection and is associated with increased mortality. The main group of enzymes responsible for collagen and protein degradation in the extracellular matrix is matrix metalloproteinases. The literature is conflicting regarding anastomotic leakage and the degradation of extracellular collagen by matrix metalloproteinase-9 (MMP-9). In this systematic review, the possible correlation between anastomotic leakage after colorectal surgery and MMP-9 activity is investigated. METHODS: Embase, MEDLINE, Cochrane, and Web of Science databases were searched up to 3 February 2020. All published articles that reported on the relationship between MMP-9 and anastomotic leakage were selected. Both human and animal studies were found eligible. The correlation between MMP-9 expression and anastomotic leakage after colorectal surgery. RESULTS: Seven human studies and five animal studies were included for analysis. The human studies were subdivided into those assessing MMP-9 in peritoneal drain fluid, intestinal biopsies, and blood samples. Five out of seven human studies reported elevated levels of MMP-9 in patients with anastomotic leakage on different postoperative moments. The animal studies demonstrated that MMP-9 activity was highest in the direct vicinity of an anastomosis. Moreover, MMP-9 activity was significantly reduced in areas further proximally and distally from the anastomosis and was nearly or completely absent in uninjured tissue. CONCLUSION: Current literature shows some relation between MMP-9 activity and colorectal AL, but the evidence is inconsistent. Innovative techniques should further investigate the value of MMP-9 as a clinical biomarker for early detection, prevention, or treatment of AL.

Outcomes of Incisional Hernia Repair Surgery After Multiple Re-recurrences: A Propensity Score Matched Analysis.

BACKGROUND: Patients with a re-recurrent hernia may account for up to 20% of all incisional hernia (IH) patients. IH repair in this population may be complex due to an altered anatomical and biological situation as a result of previous procedures and outcomes of IH repair in this population have not been thoroughly assessed. This study aims to assess outcomes of IH repair by dedicated hernia surgeons in patients who have already had two or more re-recurrences. METHODS: A propensity score matched analysis was performed using a registry-based, prospective cohort. Patients who underwent IH repair after ≥ 2 re-recurrences operated between 2011 and 2018 and who fulfilled 1 year follow-up visit were included. Patients with similar follow-up who underwent primary IH repair were propensity score matched (1:3) and served as control group. Patient baseline characteristics, surgical and functional outcomes were analyzed and compared between both groups. RESULTS: Seventy-three patients operated on after ≥ 2 IH re-recurrences were matched to 219 patients undergoing primary IH repair. After propensity score matching, no significant differences in patient baseline characteristics were present between groups. The incidence of re-recurrence was similar between groups (≥ 2 re-recurrences: 25% versus control 24%, p = 0.811). The incidence of complications, as well as long-term pain, was similar between both groups. CONCLUSION: IH repair in patients who have experienced multiple re-recurrences results in outcomes comparable to patients operated for a primary IH with a similar risk profile. Further surgery in patients who have already experienced multiple hernia re-recurrences is justifiable when performed by a dedicated hernia surgeon.

Calcification of the Aorta-Iliac Trajectory as a Risk Factor for Anastomotic Leakage in Colorectal Surgery: Individual Patient Data Meta-Analysis and Systematic Review.

OBJECTIVE: The purpose of this review is to evaluate the relevance of vascular calcification as a potential risk factor for anastomotic leakage in colorectal surgery. METHOD: The Embase, Medline, PubMed, and Cochrane databases and Google Scholar were systematically searched. Studies that assessed calcification of the aorta-iliac trajectory in patients who underwent colorectal surgery were included. An independent patient data meta-analysis was performed as follows: based on the heterogeneity of the study population, a "random-effects model" or "fixed-effects model" was used to perform a multivariable logistic regression and calculate pooled Odds Ratios (OR) and 95% confidence intervals (CI). Heterogeneity was assessed using the Q-test and I2-test. RESULTS: From a total of 457 articles retrieved, eight fell within the scope of the review, with a total of 2010 patients. Anastomotic leakage was found at a mean rate of 11.1% (SD 4.9%). In these eight studies, four different calcification scoring methods were used, which made a single structured meta-analysis not feasible. Therefore, an independent patient data meta-analysis on the most frequently used calcification scoring method was performed, including three studies with a total of 396 patients. After multivariable analyses, no significant association was found between anastomotic leakage and the amount of calcification in the aorta-iliac trajectory. The remaining three scoring methods were evaluated. In four of the five studies, vascular calcification was associated with anastomotic leakage after colorectal surgery. CONCLUSION: In contrast to previous studies, an individual patient data meta-analysis found no association between calcification and anastomotic leakage in colorectal surgery after multivariable analysis that considered a single calcification measurement method. In addition, this study demonstrated several scoring methods for arterial calcification and the need for a standardized technique. Therefore, the authors would recommend prospective studies using a calcification scoring method that includes grade of stenosis due to its potential to preoperatively improve perfusion by endovascular treatment.

Zinc-Impregnated Mesh for Abdominal Wall Repair Reduces Infection in a Rat Model of Peritonitis.

BACKGROUND: The objective of this study was to assess whether a zinc-impregnated polypropylene mesh (ZnMesh) has better antibacterial properties in a contaminated environment compared with a regular polypropylene mesh. MATERIALS AND METHODS: Thirty-eight Wistar Han rats underwent cecal ligation and puncture to induce peritonitis 24 h before implantation of an intraperitoneal ZnMesh or a regular polypropylene mesh. Primary outcome was the number of colony forming units (CFU) per sample (mesh and abdominal wall). Secondary outcomes were macroscopic (incorporation of mesh, abscesses, and adhesions on mesh surface) and histological (inflammatory cell reaction, mesh-specific parameters, and collagen deposition) parameters. All outcomes were evaluated after 30 and 90 d. RESULTS: After 30 d, no significant difference in CFU per sample was present between the ZnMesh and control groups. After 90 d, a lower number of CFU per sample was present in the ZnMesh group compared with the control group (trypticase soy agar with 5% sheep blood: 0 log10 CFU/sample IQR: 0-1.40 versus 1.58 log10 CFU/sample IQR: 0-4.30, P = 0.012; MacConkey: 0 log10 CFU/sample IQR: 0-2.65 versus 1.18 log10 CFU/sample IQR: 0-4.04, P = 0.438). After 90 d, the percentage of adhesions on mesh surface was significantly higher in the ZnMesh group (95% IQR: 60%-100% versus 50% IQR: 23%-75%, P = 0.029). No differences were seen in other macroscopic outcomes or histology. CONCLUSIONS: A significantly lower number of CFU per sample was found in the ZnMesh group after 90 d. After 30 d, no statistically significant differences in CFU per sample were seen. This result suggests that the ZnMesh group has better antibacterial properties in a contaminated environment. However, this is at the cost of a significantly higher percentage of adhesions.

Comparison of different modalities for the diagnosis of parastomal hernia: a systematic review.

PURPOSE: Parastomal hernia (PSH) is a common complication following stoma formation. The incidence of PSH varies widely due to several factors including differences in diagnostic modality, observer, definition, and classification used for diagnosing PSH. The aim of this systematic review was to evaluate the diagnostic accuracy of the modalities used to identify PSH. METHODS: Embase, MEDLINE, Cochrane, Web of Science, and Google Scholar databases were searched. Studies reporting PSH incidence rates detected by two or more different diagnostic modalities or inter-observer variation on one diagnostic modality were included. Article selection and assessment of study quality were conducted independently by two researchers using Cochrane Collaboration's tool for assessing risk of bias. PROSPERO registration: CRD42018112732. RESULTS: Twenty-nine studies (n = 2514 patients) were included. Nineteen studies compared CT to clinical examination with relative difference in incidence rates ranging from 0.64 to 3.0 (n = 1369). Overall, 79% of studies found an increase in incidence rate when using CT. Disagreement between CT and clinical examination ranged between 0 and 37.3% with pooled inter-modality agreement Kappa value of 0.64 (95% CI 0.52-0.77). Four studies investigated the diagnostic accuracy of ultrasonography (n = 103). Compared with peroperative diagnosis, CT and ultrasonography both seemed accurate imaging modalities with a sensitivity of 83%. CONCLUSION: CT is an accurate diagnostic modality for PSH diagnosis and increases PSH detection rates, as compared with clinical examination. Studies that specially focus on the diagnostic accuracy are needed and should aim to take patient-reported outcomes into account. A detailed description of the diagnostic approach, modality, definition, and involved observers is prerequisite for future PSH research.

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.

Outcomes After Elective Colorectal Surgery by 2 Surgeons Versus 1 Surgeon in a Low-Volume Hospital.

Background. Improved patient outcomes after colorectal surgery in high-volume hospitals are leading to centralization of colorectal surgery. However, it is desirable to strive for optimal quality of colorectal surgery in low-volume hospitals. This study aimed to assess the effect of the number of surgeons involved in the surgical procedure on patient outcomes in a low-volume hospital. Methods. All patients who underwent elective colorectal surgery with construction of a primary anastomosis between January 1, 2007, and December 31, 2015, were included in this retrospective cohort. The propensity score was used to adjust for confounding. Results. A total of 429 patients were included. One hundred forty-three patients (33.3%) were operated by 1 surgeon and 286 patients (66.7%) were operated by 2 surgeons. Patients operated by 2 surgeons were younger, more often male, and had a higher body mass index. A multivariate analysis with propensity scores revealed that surgery with 2 surgeons was associated with fewer reoperations (odds ratio [OR] = 0.4, 95% confidence interval [CI] = 0.2-0.9, P = .038). Colorectal anastomotic leakage (OR = 0.6, 95% CI = 0.2-1.3, P = .204) and mortality (OR = 0.8, 95% CI = 0.2-3.7, P = .807) were not associated with the number of surgeons involved in the surgical procedure. Conclusion. The present study shows that elective colorectal surgery in a low-volume hospital performed by 2 surgeons resulted in fewer reoperations. This might positively influence patient outcomes and might be related to increased surgical quality as compared with procedures performed by only 1 surgeon.

Different Risk Factors for Early and Late Colorectal Anastomotic Leakage in a Nationwide Audit.

BACKGROUND: Anastomotic leakage remains a major complication after surgery for colorectal carcinoma, but its origin is still unknown. Our hypothesis was that early anastomotic leakage is mostly related to technical failure of the anastomosis, and that late anastomotic leakage is mostly related to healing deficiencies. OBJECTIVE: The aim of this study was to assess differences in risk factors for early and late anastomotic leakage. DESIGN: This was a retrospective cohort study. SETTINGS: The Dutch ColoRectal Audit is a nationwide project that collects information on all Dutch patients undergoing surgery for colorectal cancer. PATIENTS: All patients undergoing surgical resection for colorectal cancer in the Netherlands between 2011 and 2015 were included. MAIN OUTCOME MEASURES: Late anastomotic leakage was defined as anastomotic leakage leading to reintervention later than 6 days postoperatively. RESULTS: In total, 36,929 patients were included; early anastomotic leakage occurred in 863 (2.3%) patients, and late anastomotic leakage occurred in 674 (1.8%) patients. From a multivariable multinomial logistic regression model, independent predictors of early anastomotic leakage relative to no anastomotic leakage and late anastomotic leakage relative to no anastomotic leakage included male sex (OR, 1.8; p < 0.001 and OR, 1.2; p = 0.013) and rectal cancer (OR, 2.1; p < 0.001 and OR, 1.6; p = 0.046). Additional independent predictors of early anastomotic leakage relative to no anastomotic leakage included BMI (OR, 1.1; p = 0.001), laparoscopy (OR, 1.2; p = 0.019), emergency surgery (OR, 1.8; p < 0.001), and no diverting ileostomy (OR, 0.3; p < 0.001). Independent predictors of late anastomotic leakage relative to no anastomotic leakage were Charlson Comorbidity Index of ≥II (OR, 1.3; p = 0.003), ASA score III to V (OR, 1.2; p = 0.030), preoperative tumor complications (OR, 1.1; p = 0.048), extensive additional resection because of tumor growth (OR, 1.7; p = 0.003), and preoperative radiation (OR, 2.0; p = 0.010). LIMITATIONS: This was an observational cohort study. CONCLUSIONS: Most risk factors for early anastomotic leakage were surgery-related factors, representing surgical difficulty, which might lead to technical failure of the anastomosis. Most risk factors for late anastomotic leakage were patient-related factors, representing the frailty of patients and tissues, which might imply healing deficiencies. See Video Abstract at http://links.lww.com/DCR/A730.

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

BACKGROUND: The aim of this study was to investigate the effect of age on CAL and its associated mortality. METHODS: Data were derived from the Dutch ColoRectal Audit. All patients undergoing resection for colorectal cancer in the Netherlands between January 2011 and December 2016 were included. Univariable and multivariable logistic regressions were performed to test the effect of age on CAL and its associated mortality. RESULTS: In total, 45 488 patients were included. The incidence of CAL was 6.4% in patients <60 years old, 5.5% in patients 60-69 years old, 5.4% in patients 70-80 years old, and 4.9% in patients ≥80 years old (P < 0.001). Multivariate analysis showed that age was protective for CAL (OR 0.965 per 5 years, 95% CI 0.941-0.985, P < 0.001). Mortality after CAL was 1.3% in patients <60 years old, 4.8% in patients 60-69 years old, 12.3% in patients 70-80 years old, and 27.0% in patients >80 years old (P < 0.001). Older age was associated with mortality following CAL (OR 1.497 per 5 years 95% CI 1.364-1.647, P < 0.001). CONCLUSIONS: This population-based study suggests a protective effect of increased age on CAL after colorectal cancer resection. However, older age is strongly associated with mortality after CAL.

Reinforcement of the colon anastomosis with cyanoacrylate glue: a porcine model.

BACKGROUND: Previous experimental studies on cyanoacrylate (CA) glue for the prevention of colorectal anastomotic leakage (AL) have shown promising results. The aim of this study was to investigate the effect of CA in prevention of leakage in a porcine model of ischemic colorectal AL. METHODS: Twenty-four animals were divided into four groups of six: (1)ischemic anastomosis with sufficient suture (ISCH), (2)ischemic anastomosis with sufficient suture and CA reinforcement (CA-ISCH), (3)ischemic anastomosis with insufficient suture (ISCH-AI), and (4)ischemic anastomosis with insufficient suture and CA reinforcement (CA-ISCH-AI). In CA groups, N-butyl-2-cyanoacrylate was applied between the colon ends. Anastomotic bursting pressure, abscess formation, and adhesion formation were evaluated on postoperative day 7. Tissue samples were obtained for histologic evaluation of foreign body reaction. RESULTS: The AL rate was 4 of 6 (67%) in the ISCH-AI group compared with none in the other three groups. The ISCH and ISCH-AI groups had significantly higher AL scores compared with the CA groups. The mean anastomotic bursting pressure was 167 ± 54 mm Hg in the ISCH-group versus 213 ± 43 mm Hg in the CA-ISCH-group (P = nonsignificant) and 145 ± 102 mm Hg in the ISCH-AI group versus 187 ± 19 mm Hg in the CA-ISCH-AI group (P = nonsignificant). The average adhesion score was significantly higher in the ISCH group than in the CA-ISCH group (4.2 ± 1.3 versus 1.7 ± 0.82; P = 0.019). Stricture of the anastomosis occurred only in the non-CA groups (3/12, 25%). CONCLUSIONS: Anastomotic reinforcement with CA is effective and safe to prevent leakage in a high-risk colorectal anastomosis in a porcine model.

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.

Nicotine chewing gum for the prevention of postoperative ileus after colorectal surgery: a multicenter, double-blind, randomised, controlled pilot study.

PURPOSE: When postoperative ileus is not resolved after 5 days or recurs after resolution, prolonged POI (PPOI) is diagnosed. PPOI increases discomfort, morbidity and hospitalisation length, and is mainly caused by an inflammatory response following intestinal manipulation. This response can be weakened by targeting the cholinergic anti-inflammatory pathway, with nicotine as essential regulator. Chewing gum, already known to stimulate gastrointestinal motility itself, combined with nicotine is hypothesised to improve gastrointestinal recovery and prevent PPOI. This pilot study is the first to assess efficacy and safety of nicotine gum in colorectal surgery. METHODS: Patients undergoing elective oncological colorectal surgery were enrolled in this double-blind, parallel-group, controlled trial and randomly assigned to a treatment protocol with normal or nicotine gum (2 mg). Patient reported outcomes (PROMS), clinical characteristics and blood samples were collected. Primary endpoint was defined as time to first passage of faeces and toleration of solid food for at least 24 h. RESULTS: In total, 40 patients were enrolled (20 vs. 20). In both groups, six patients developed PPOI. Time to primary endpoint (4.50 [3.00-7.25] vs. 3.50 days [3.00-4.25], p = 0.398) and length of stay (5.50 [4.00-8.50] vs. 4.50 days [4.00-6.00], p = 0.738) did not differ significantly between normal and nicotine gum. There were no differences in PROMS, inflammatory parameters and postoperative complications. CONCLUSIONS: We proved nicotine gum to be safe but ineffective in improving gastrointestinal recovery and prevention of PPOI after colorectal surgery. Other dosages and administration routes of nicotine should be tested in future research.

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. Hartmann's 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.

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 (R(2) = 0.52; P < .001) and in the rats with colitis (R(2) = 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.

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.

Monocyte response after colorectal surgery: A prospective cohort study.

Background: Tumor resection is the common approach in patients with colorectal malignancy. Profound insight into inflammatory changes that accompany the normal post-operative stress response will establish reference parameters useful for identification of putative complications. Alterations in circulating monocytes might be indicative as these cells are considered to be the most responsive leukocytes to trauma. Therefore, the aim of this study is to assess the monocyte subset kinetic and phenotypic changes in response to surgery. Methods: Fifty patients undergoing colorectal tumor resection were included in a multicenter prospective cohort study. Blood samples were collected early in the morning prior to surgery and the next days through postoperative day three for flowcytometric analysis. Leukocyte subtypes were identified and expression of activation stage-related markers by monocyte subsets was quantified. Results: Changes in leukocyte subset composition and monocyte subset phenotypes were most prominent at the first day postoperatively, after which these parameters typically returned to normal or near-normal preoperative values. The immunophenotypic alterations after surgery were most notable in classical and intermediate monocytes. These included up-regulation of activation markers CD64 and CD62L, but down-regulation of HLA-DR and CD54. Markers of de-activation, CD163 and CD206, were consistently increasingly expressed. Discussion/conclusion: The current study gives detailed insight into the peripheral blood leukocyte response after colorectal cancer surgery. This form of short-term stress induces a rapid and significant redistribution of immune cells. Immunophenotypic alterations in monocytes as a response to surgery suggest a mixed profile of cellular activation and de-activation.