P Holzner

Intraoperative crystalloid overload leads to substantial inflammatory infiltration of intestinal anastomoses—a histomorphological analysis

BACKGROUND It has been shown that crystalloid fluid-overload promotes anastomotic instability. As physiologic anastomotic healing requires the sequential infiltration of different cells, we hypothesized this to be altered by liberal fluid regimes and performed a histomorphological analysis. METHODS 36 Wistar rats were randomized into 4 groups (n=8-10 rats/group) and treated with either liberal (+) or restrictive (-) perioperative crystalline (Jonosteril = Cry) or colloidal fluid (Voluven = Col). Anastomotic samples were obtained on postoperative day 4, routinely stained and histophathologically reviewed. Anastomotic healing was assessed using a semiquantitative score, assessing inflammatory cells, anastomotic repair and collagenase activity. RESULTS Overall, the crystalloid overload group (Cry (+)) showed the worst healing score (P < 0.01). A substantial increase of lymphocytes and macrophages was found in this group compared to the other three (P < 0.01). Both groups that received colloidal fluid (Col (+) and Col (-)) as well as the group that received restricted crystalloid fluid resuscitation (Cry (-)) had better intestinal healing. Collagenase activity was significantly higher in the Cry (+) group. CONCLUSION Intraoperative infusion of high-volume crystalloid fluid leads to a pathological anastomotic inflammatory response with a marked infiltration of leukocytes and macrophages resulting in accelerated collagenolysis.

Pitfalls and Technical Aspects during the Research of Intestinal Anastomotic Healing in Rats

Background: Fundamental experimental research into intestinal anastomotic healing in rodent models will gain increasing interest in the future. Methods: The aim of this study was to describe our 5-year experience with a standardized experimental setup of small and large bowel anastomoses in a rodent model and present a basic set of assessment tools investigating anastomotic healing. Anastomotic technique, perioperative complications such as anastomotic insufficiency (AI) and obstructive ileus were in the focus. Results: During different studies with varying study patterns, 167 rat small bowel anastomoses and 120 colonic anastomoses were performed. Overall mortality was 3.6% in small bowel and 2.5% in colonic anastomoses, AI occurred in 2.9 and 4%, respectively. A postoperative obstructive ileus was seen in 3/167 small bowel anastomoses and none in the colonic group. Conclusion: When performing experimental intestinal anastomoses in a standardized operative setting and critically considering special perioperative issues, the incidence of relevant complications can be maintained at an adequately low level.

Impact of remote ischemic preconditioning on wound healing in small bowel anastomoses

AIM To investigate the influence of remote ischemic preconditioning (RIPC) on anastomotic integrity. METHODS Sixty male Wistar rats were randomized to six groups. The control group (n = 10) had an end-to-end ileal anastomosis without RIPC. The preconditioned groups (n = 34) varied in time of ischemia and time of reperfusion. One group received the amino acid L-arginine before constructing the anastomosis (n = 9). On postoperative day 4, the rats were re-laparotomized, and bursting pressure, hydroxyproline concentration, intra-abdominal adhesions, and a histological score concerning the mucosal ischemic injury were collected. The data are given as median (range). RESULTS On postoperative day 4, median bursting pressure was 124 mmHg (60-146 mmHg) in the control group. The experimental groups did not show a statistically significant difference (P > 0.05). Regarding the hydroxyproline concentration, we did not find any significant variation in the experimental groups. We detected significantly less mucosal injury in the RIPC groups. Furthermore, we assessed more extensive intra-abdominal adhesions in the preconditioned groups than in the control group. CONCLUSION RIPC directly before performing small bowel anastomosis does not affect anastomotic stability in the early period, as seen in ischemic preconditioning.

Searching for the Molecular Benchmark of Physiological Intestinal Anastomotic Healing in Rats: An Experimental Study

Purpose: This investigation focuses on the physiological characteristics of gene transcription of intestinal tissue following anastomosis formation. Methods: In eight rats, end-to-end ileo-ileal anastomoses were performed (n = 2/group). The healthy intestinal tissue resected for this operation was used as a control. On days 0, 2, 4 and 8, 10-mm perianastomotic segments were resected. Control and perianastomotic segments were examined with an Affymetrix microarray chip to assess changes in gene regulation. Microarray findings were validated using real-time PCR for selected genes. In addition to screening global gene expression, we identified genes intensely regulated during healing and also subjected our data sets to an overrepresentation analysis using the Gene Ontology (GO) and Kyoto Encyclopedia for Genes and Genomes (KEGG). Results: Compared to the control group, we observed that the number of differentially regulated genes peaked on day 2 with a total of 2,238 genes, decreasing by day 4 to 1,687 genes and to 1,407 genes by day 8. PCR validation for matrix metalloproteinases-3 and -13 showed not only identical transcription patterns but also analogous regulation intensity. When setting the cutoff of upregulation at 10-fold to identify genes likely to be relevant, the total gene count was significantly lower with 55, 45 and 37 genes on days 2, 4 and 8, respectively. A total of 947 GO subcategories were significantly overrepresented during anastomotic healing. Furthermore, 23 overrepresented KEGG pathways were identified. Conclusion: This study is the first of its kind that focuses explicitly on gene transcription during intestinal anastomotic healing under standardized conditions. Our work sets a foundation for further studies toward a more profound understanding of the physiology of anastomotic healing.

A Prospective Clinical Study Evaluating the Development of Bowel Wall Edema During Laparoscopic and Open Visceral Surgery

BackgroundTo examine bowel wall edema development in laparoscopic and open major visceral surgery.MethodsIn a prospective study, 47 consecutively operated patients with gastric and pancreatic resections were included. Twenty-seven patients were operated in a conventional open procedure (open group) and 20 in a laparoscopic fashion (lap group). In all procedures, a small jejunal segment was resected during standard preparation, of which we measured the dry-wet ratio. Furthermore, HE staining was performed for measuring of bowel wall thickness and edema assessment.ResultsMean value (±std) of dry-wet ratio was significantly lower in the open than in the lap group (0.169 ± 0.017 versus 0.179 ± 0.015; p = 0.03) with the same amount of fluid administration in both groups and a longer infusion interval during laparoscopic surgery. Subgroup analyses (only pancreatic resections) still showed similar results. Histologic examination depicted a significantly larger bowel wall thickness in the open group.ConclusionsLaparoscopic surgery does not seem to lead to the bowel wall edema observed to occur in open surgery regardless of the degree of intravenous fluid administration, thus supporting its use even in major visceral surgery.

Double 90 Degrees Counterrotated End-to-End-Anastomosis: An Experimental Study of an Intestinal Anastomosis Technique.

AIM The aim of the article is to investigate a new anastomotic technique compared with standardized intestinal anastomotic procedures. MATERIALS AND METHODS A total of 32 male Wistar rats were randomized to three groups. In the Experimental Group (n = 10), the new double 90 degrees inversely rotated anastomosis was used, in the End Group (n = 10) a single-layer end-to-end anastomosis, and in the Side Group (n = 12) a single-layer side-to-side anastomosis. All anastomoses were done using interrupted sutures. On postoperative day 4, rats were relaparotomized. Bursting pressure, hydroxyproline concentration, a semiquantitative adhesion score and two histological anastomotic healing scores (mucosal healing according to Chiu and overall anastomotic healing according to Verhofstad) were collected. Most data are presented as median (range). p < 0.05 was considered significant. RESULTS Anastomotic insufficiency occurred only in one rat of the Side Group. Median bursting pressure in the Experimental Group was 105 mm Hg (range = 72-161 mm Hg), significantly higher in the End Group (164 mm Hg; range = 99-210 mm Hg; p = 0.021) and lower in the Side Group by trend (81 mm Hg; range = 59-122 mm Hg; p = 0.093). Hydroxyproline concentration did not differ significantly in between the groups. The adhesion score was 2.5 (range = 1-3) in the Experimental Group, 2 (range = 1-2) in the End Group, but there were significantly more adhesions in the Side Group (range = 3-4); p = 0.020 versus Experimental Group, p < 0.001 versus End Group. The Chiu Score showed the worst mucosal healing in the Experimental Group. The overall Verhofstad Score was significantly worse (mean = 2.032; standard deviation [SD] = 0.842) p = 0.031 and p = 0.002 in the Experimental Group, compared with the Side Group (mean = 1.729; SD = 0.682) and the End Group (mean = 1.571; SD = 0.612). CONCLUSION The new anastomotic technique is feasible and did not show any relevant complication. Even though it was superior to the side-to-side anastomosis by trend with respect to functional stability, mucosal healing surprisingly showed the worst results. Classical end-to-end anastomosis still seems to be the best choice regarding structural and functional anastomotic stability.

Does the site of primary colorectal cancer influence the outcome after resection of isolated liver metastases

INTRODUCTION In unresectable patients with metastatic colorectal cancer (CRC), the site of the primary is a strong prognostic factor warranting major adjustments in palliative medical treatment. Initial results suggested that the site of CRC influences prognosis after curative resection of colorectal liver metastases (CLM). In this study, we evaluated outcome after resection of isolated CLM with regard to the location of the primary. METHODS 221 patients with macroscopically complete resection of CLM and no known extrahepatic disease were identified. 63 patients had right-sided and 158 had left-sided CRC. Tumors of the transverse colon and rectum were excluded. Survival was evaluated using the Kaplan-Meier method. RESULTS Characteristics of CLM, primary tumor stage and chemotherapeutic regimens were not significantly different between the two groups. Kaplan-Meier five-year survival was comparable (41%) in patients with right- or left-sided CRC (p = 0.64). Microscopic resection margin, number of liver metastases, age and nodal status but not the site of the primary tumor significantly influenced survival. CONCLUSION The site of the colorectal primary in this well-defined group of patients after resection of isolated CLM did not prove to be of significant prognostic value. Whether the primary tumor in CLM is located on the left side or the right should not preclude patients from surgery.

An Unusual Cecal Mass in an Otherwise Healthy Young Woman

DIS 5.4.0 DTD YGAST60188 proof 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 Question: A 25-year-old woman presented to her primary care physician for mild right upper quadrant pain. Apart from the patient being an avid kickboxer, no noteworthy abdominal trauma was recalled. Because of an inconclusive ultrasound examination, showing no gallstones, together with elevated liver enzymes an abdominal magnetic resonance imaging study was ordered. A 7 4.5 4-cm mass in contact to the cecum was seen. The elliptically shaped smooth cystic lesion showed a hypointense outer lining on T2 haste sequences with a relatively homogenous hyperintense cyst content (Figure A). Contact to the cecum was well-established on consecutive 5-mm slices. Because no conclusive diagnosis could be established after interdisciplinary review, the case surgical removal was chosen over fine needle aspiration and colonoscopy. Fine needle aspiration was discussed because of the solid appearanceof themass. Itwasnot chosen in anoninfiltrating process because of the risk of tumor seeding. The elliptical shape did not support the diagnosis of a large cecal diverticulum. Because of the largely extracolonic appearance a colonoscopy was not ordered in this 25-year-old woman. 91 92 93 94 95 At the time of surgery, there were no abnormal laboratory findings, including liver function tests, that led to the initial diagnostic workup. What is the most likely diagnosis? See the Gastroenterology web site (www.gastrojournal.org) for more information on submitting your favorite image to Clinical Challenges and Images in GI. 96 97 98 99 100 101 102 Conflicts of interest The authors disclose no conflicts.

Contents Vol. 53, 2014

I. Alwayn, Halifax D.K. Bartsch, Marburg C. Bassi, Verona W.O. Bechstein, Frankfurt am Main J.A. Bradley, Cambridge M. Cikirikcioglu, Geneva P.-A. Clavien, Zurich R.W.F. de Bruin, Rotterdam C. Eipel, Rostock S. Fichtner-Feigl, Regensburg H. Friess, Munich G. Galata, London D.J. Gouma, Hilversum J.K. Habermann, Lübeck M. Heberer, Basel M. Heger, Amsterdam T. Hubert, Lille W.R. Jarnagin, New York, N.Y. J.C. Kalff, Bonn M.W. Laschke, Homburg/Saar H.-A. Lehr, Lausanne C.M. Malata, Cambridge T. Minor, Bonn M. Morino, Torino J. Pirenne, Leuven A. Schachtrupp, Melsungen R. Schramm, Munich L. Steinstraesser, Bochum A. Szijártó, Budapest R.H. Tolba, Aachen T.M. van Gulik, Amsterdam M.A. Venermo, Helsinki D.C. Winter, Dublin Y. Yamamoto, Akita Clinical and Experimental Surgery