Postoperative adhesion prevention with a new barrier: an experimental study.

INTRODUCTION: Postoperative adhesion formation remains a major clinical problem. The aim of this study was to test the effect of a new hydrogel on adhesion formation in a rat model. MATERIALS AND METHODS: A reproducible rat model was used to induce standardized adhesion formation in three experiments. In experiment 1, a cross-linked polyvinyl alcohol (PVA) and carboxymethylcellulose (CMC) hydrogel (PVA/CMC, A-Part®; B. Braun Aesculap, Germany) was tested in different dosages. In experiment 2, PVA/CMC gel was compared to icodextrin 4% (Adept®; Baxter USA). In both groups, animals were sacrificed after 2 weeks. In experiment 3, histological examination after 4 and 6 weeks was performed. The percentage of adhesions to the defect was measured and the density was determined according to the Zühlke scale. During histological examination of the abdominal wall, the formation of neoperitoneum and potential residues of the agents were assessed. RESULTS: In experiment 1, a significant reduction in amount as well as density of the adhesions was visible with all dosages of PVA/CMC gel. In experiment 2, again quantity and density of the adhesions were diminished by PVA/CMC hydrogel compared to the control group. Icodextrin 4% showed no significant reduction in adhesion formation. In experiment 3, no residues of PVA/CMC gel or icodextrin 4% were found during histological examination after 4 and 6 weeks and neoperitoneum was present in all cases. CONCLUSION: PVA/CMC hydrogel appears to be a novel effective adhesion prevention agent. Together with an upcoming safety study, these data encourage to start clinical efficacy studies.

Scavenging of reactive oxygen species leads to diminished peritoneal tumor recurrence.

Previously, we demonstrated that RBCs inhibit the recurrence of perioperatively spilled tumor cells. The aim of this study was to identify on which RBC component(s) the inhibitory effect is based. By using a cell-seeding model in rats, the effect of RBC-related antioxidant scavengers [hemoglobin, catalase, and superoxide dismutase (SOD)] on peritoneal tumor recurrence was investigated. i.p. injection of hemoglobin caused 45% more tumor load (P < 0.0001). At least 40% inhibition of tumor recurrence was achieved with the use of catalase or SOD (P < 0.05). Combining SOD and catalase did not lead to additional inhibition of tumor recurrence. Inhibition of the overwhelming oxidative potential after surgical peritoneal trauma with the use of scavengers may lead to interesting new approaches for diminishing peritoneal tumor recurrence.

2016 WSES guidelines on acute calculous cholecystitis.

Acute calculus cholecystitis is a very common disease with several area of uncertainty. The World Society of Emergency Surgery developed extensive guidelines in order to cover grey areas. The diagnostic criteria, the antimicrobial therapy, the evaluation of associated common bile duct stones, the identification of "high risk" patients, the surgical timing, the type of surgery, and the alternatives to surgery are discussed. Moreover the algorithm is proposed: as soon as diagnosis is made and after the evaluation of choledocholitiasis risk, laparoscopic cholecystectomy should be offered to all patients exception of those with high risk of morbidity or mortality. These Guidelines must be considered as an adjunctive tool for decision but they are not substitute of the clinical judgement for the individual patient.

Erratum to: 2016 WSES guidelines on acute calculous cholecystitis.

[This corrects the article DOI: 10.1186/s13017-016-0082-5.].

Small bowel transplantation in rats. The effect of pretransplant donor-specific blood transfusions on various segments of small bowel grafts.

The effects of pretransplant donor-specific blood transfusion on the survival of orthotopic small bowel transplants in rats were investigated in the fully allogeneic BN (Rt1n) to WAG (Rt1u) donor-host combination. Previous studies show that in this combination DSTs lead to permanent survival of heterotopically transplanted hearts, marked prolongation of kidney grafts, and moderate prolongation of pancreas grafts but have no effect on skin grafts. Without pretreatment, total small bowel grafts (+/- 45 cm) were rejected in 12.2 +/- 1.8 days (mean +/- SD), and 10-cm segments of jejunum or ileum in 11.2 +/- 4.0 and 11.6 +/- 0.5 days, respectively. Three DSTs given on days -21, -14, and -7 before transplantation had no effect on graft survival in any of the groups tested. Total small bowel grafts were rejected in 12.8 +/- 2.5 days, and 10-cm-long segments or jejunum or ileum in 17.0 +/- 7.2 days and 11.5 +/- 2.7 days, respectively. Graft-versus-host disease, which was mild and transient, occurred in 50% of the nontreated rats engrafted with a total small bowel, in 40% of the animals transplanted with an ileum segment, and in none of the rats that received a jejunal transplant. In the DST-pretreated groups, none of the animals transplanted with a total small bowel or ileum segment and 16.6% of the animals transplanted with a jejunum segment showed clinical signs of GVHD. When DST pretreatment was combined with cyclosporine, grafts did not survive any longer than with cyclosporine treatment alone. It is concluded that DSTs ameliorate GVHD but do not prolong the survival of small bowel allografts nor act additively with cyclosporine treatment.

The occurrence of diversion colitis in patients with a sigmoid neovagina.

Diversion colitis is an inflammatory process occurring in segments of the colorectum surgically diverted from the fecal stream. Clinical symptoms of this condition are rectal discomfort, pain, discharge, and bleeding. We diverted isolated segments of sigmoid to create neovaginas in patients with aplasia vaginae and in male to female transsexuals. In contrast to what is reported in most studies of diversion colitis, the neovagina consists of an isolated segment not connected to the anus in patients without any pre-existing bowel disease. To investigate the occurrence of diversion colitis in these sigmoid-neovaginas we studied biopsy specimens from 13 patients. Most of the patients complained of discharge and slight blood loss from their sigmoid-neovagina. Microscopic examination of the biopsy specimens showed lymphocytic infiltration in all cases. Four cases showed an acute inflammatory infiltrate in the lamina propria. Our results indicate that the changes observed on clinical and histopathologic examinations represent the entity of mild diversion colitis. We conclude that diversion colitis also occurs in a sigmoid neovagina.

Prolapse of the sigmoid neovagina: report of three cases.

BACKGROUND: Prolapse of a sigmoid neovagina, created in patients with congenital vaginal aplasia or male transsexualism, is rare. In correcting this condition, preservation of coital function and restoration of the vaginal axis should be of primary interest. CASES: One patient with Mayer-Rokitansky-Küster syndrome developed a protrusion of the sigmoid neovagina almost 4 years after the initial operation. The prolapse was treated successfully using an abdominal approach to suspend the neovagina to a Cooper ligament. The second patient is a male-to-female transsexual who developed a prolapse 3 years after the creation of a sigmoid neovagina. After suspension of the neovagina to a Cooper ligament, the prolapse recurred; in a repeat approach, the neovagina was successfully suspended to the sacral promontory. The third patient, with Mayer-Rokitansky-Küster syndrome, complained of a protrusion immediately after creation of the neovagina. Initially, the redundant sigmoid was resected vaginally. However, the prolapse recurred, and an abdominal suspension to a Cooper ligament was performed. Finally, after 1 year, another recurrence was treated successfully with a vaginal approach. CONCLUSION: Prolapse of an artificially created vagina is a rare occurrence, without a standard treatment. Both abdominal and vaginal approaches may be needed to restore the neovagina without compromising its function.

Recurrent inguinal hernia treated by classical hernioplasty.

The treatment of recurrent inguinal hernia by classical hernioplasty, ie, via the anterior approach and using endogenous tissue for repair, was evaluated in 163 patients operated on between 1980 and 1987. One hundred fifteen patients had a first recurrence and 48 had a multiple recurrence; 58% were of the direct type; 30% were of the indirect type; 7% were of the combined type; and 5% were not defined. In 1989 a questionnaire was sent to all patients; those indicating symptoms of recurrence underwent further examination. There was a mean follow-up of 52 months and a total follow-up period of 706 years. Thirty-seven patients had a repeated recurrence with a cumulative recurrence rate of 16%, 21%, and 23%, after 1, 2, and 5 years, respectively. Increase of age and time passed since the last repair reduced the recurrence rate. Increased abdominal pressure, type of anesthesia or surgical technique, and wound hematoma had no effect. It is concluded that the technique of classical hernioplasty as such may be unsuitable for repair of recurrent inguinal hernias.

Effects of carbon dioxide pneumoperitoneum, air pneumoperitoneum, and gasless laparoscopy on body weight and tumor growth.

BACKGROUND: The oncologic consequences of intraperitoneal carbon dioxide (CO2) insufflation during the laparoscopic resection of cancer are under debate. The effect of other insufflating gases or gasless laparoscopy on cancer requires study. OBJECTIVE: To study body weight and tumor growth in rats after CO2 pneumoperitoneum, air pneumoperitoneum, and gasless laparoscopy. METHODS: On day 1, an 8-mg bolus of ROS-1 tumor was placed under the renal capsule of both kidneys in rats. In experiment A, rats had either CO2 insufflation (n=10) or a gasless laparoscopic bowel resection (n=10) on day 3 and were humanely killed after 7 days. In experiment B, rats had either a laparoscopic bowel resection with CO2 insufflation (n=11) or insufflation with air (n=11) on day 3 and were killed after 7 days. In both experiments, postoperative weight loss and tumor growth were measured, and the differences were tested with an analysis of covariance. RESULTS: Renal subcapsular tumor growth in the group having gasless laparoscopy was less than that in the group having CO2 pneumoperitoneum (P=.04). Postoperative weight loss in these groups showed no differences (P=.55). No differences in tumor growth or weight loss were found between rats having insufflation with CO2 and those having insufflation with air (P=.61 and P=.68, respectively). CONCLUSIONS: The restoration of body weight after a laparoscopic surgical procedure was similar with CO2, air, or gasless laparoscopy. Gasless laparoscopy was associated with less renal subcapsular tumor growth than was insufflation with CO2. Therefore, the application of gasless techniques in laparoscopic oncologic surgical treatment demands further study.

Meta-analysis of randomised adjuvant therapy trials for pancreatic cancer.

The aim of this study was to investigate the worldwide evidence of the roles of adjuvant chemoradiation and adjuvant chemotherapy on survival in potentially curative resected pancreatic cancer. Five randomised controlled trials of adjuvant treatment in patients with histologically proven pancreatic ductal adenocarcinoma were identified, of which the four most recent trials provided individual patient data (875 patients). This meta-analysis includes previously unpublished follow-up data on 261 patients. The pooled estimate of the hazard ratio (HR) indicated a 25% significant reduction in the risk of death with chemotherapy (H = 0.75, 95% confidence interval (CI): 0.64, 0.90, P-values(stratified) (Pstrat) = 0.001) with median survival estimated at 19.0 (95% CI: 16.4, 21.1) months with chemotherapy and 13.5 (95% CI: 12.2, 15.8) without. The 2- and 5-year survival rates were estimated at 38 and 19%, respectively, with chemotherapy and 28 and 12% without. The pooled estimate of the HR indicated no significant difference in the risk of death with chemoradiation (HR = 1.09, 95% CI: 0.89, 1.32, Pstrat = 0.43) with median survivals estimated at 15.8 (95% CI: 13.9, 18.1) months with chemoradiation and 15.2 (95% CI: 13.1, 18.2) without. The 2- and 5-year survival rates were estimated at 30 and 12%, respectively, with chemoradiation and 34 and 17% without. Subgroup analyses estimated that chemoradiation was more effective and chemotherapy less effective in patients with positive resection margins. These results show that chemotherapy is effective adjuvant treatment in pancreatic cancer but not chemoradiation. Further studies with chemoradiation are warranted in patients with positive resection margins, as chemotherapy appeared relatively ineffective in this patient subgroup.

Cost implications of adhesions as highlighted in a European study.

For a hospital, the medical costs of dealing with post-operative adhesions can be very high. Studies to determine the extent of these costs are described, together with a suggested strategy by which surgeons may help avoid future cases of adhesion formation.

Long-term psychosexual and psychosocial performance of patients with a sigmoid neovagina.

OBJECTIVE: We aimed to study the long-term psychosexual and psychosocial performance of patients with a sigmoid vagina in vaginal dysgenesis and male-to-female transsexuals. STUDY DESIGN: Nineteen patients who had undergone surgery to create a neovagina with the use of a sigmoid segment participated in a long-term follow-up study. Evaluation was done with standardized gynecologic examination and a structured interview. RESULTS: The anatomic result was good in 18 patients, although several reoperative procedures had been necessary. Sexual adjustment was good or satisfactory in 12 of 19 patients. Of the 19 patients, 16 were capable of reaching an organism. Social adjustment was good or satisfactory in 16 patients. CONCLUSIONS: The creation of a sigmoid neovagina results in a long-term anatomically satisfactory situation, in both patients with vaginal dysgenesis and male-to-female transsexuals. In a majority of the patients sexual and social adjustment is good or satisfactory.

Transient protection of incomplete colonic anastomoses with fibrin sealant: an experimental study in the rat.

Fibrin glue has been used as a protective seal in normal and high-risk anastomoses to prevent leakage. The influence of fibrin adhesive on the healing colonic anastomosis in a control and high-risk model was tested. Resection and anastomosis of the left colon was performed in rats. In group Ia an end-to-end anastomosis was constructed with 12 7-O polypropylene sutures; in group Ib the anastomosis was sealed with fibrin adhesive. In group II an incomplete anastomosis was constructed with only 4 sutures at 90 degrees, therefore potentially leaking. In group IIb additional sealing with fibrin glue was performed. On Days 2, 4, and 7 body weight, adhesion formation, anastomotic bursting pressure, and collagen concentration were measured. The results showed increased adhesion formation after fibrin sealing. The anastomotic bursting pressure of incomplete anastomoses showed a significant increase after sealing on Day 2 only; on Day 4 and 7 no differences were found. Sealing of control anastomoses caused lower bursting pressures on Day 4. Collagen concentration is significantly reduced after fibrin sealing of normal anastomoses. We conclude that fibrin sealing of control anastomoses inhibits wound healing. Incomplete anastomoses are temporarily protected by fibrin glue sealing. Finally, fibrin sealing of the colon wound does not prevent adhesion formation.

Efficacy of recombinant erythropoietin for stimulating erythropoiesis after blood loss and surgery. An experimental study in rats.

Perioperative administration of recombinant human erythropoietin (rEpo) may reduce the need for allogeneic blood transfusions by diminishing the time lag between blood loss and erythropoiesis and by generating more adequate Epo levels. The efficacy of pre- and postoperative rEpo was studied in rats subjected to blood loss (20% of the blood volume) and surgery (ileal resection). After 200 U rEpo/kg daily for 5 days postoperatively, hemoglobin had increased by 15.7 g/l in these rats but by 36.9 g/l in rEpo-treated controls without surgery (p less than 0.05), indicating an inhibitory effect of surgery on erythropoiesis. A course of 200 U rEpo/kg/day for 5 days, starting 4 or 2 days before operation and blood loss, resulted in significantly higher postoperative hemoglobin levels than in untreated controls. Such difference did not occur if rEpo treatment was begun on the day of operation. Prolonged (10-day) postoperative rEpo treatment was of minor benefit, inducing significant increase in hemoglobin and hematocrit only from day 8 onwards. The study indicates that rEpo is a promising agent to obviate need for perioperative blood transfusions, provided that the treatment is begun before operation.

A modified technique to create a neovagina with an isolated segment of sigmoid colon.

The creation of a functional vagina in patients with congenital vaginal aplasia or male transsexualism is a challenging problem. A group of 40 patients, including 23 male transsexuals, in whom a neovagina was created using a sigmoid transplant, is reported. The technique, a modification of Kun's "colocolpopoiesis," is described in detail. Ten patients showed some direct postoperative complications and five were readmitted the first six weeks postoperatively for a variety of reasons. No extensive complication occurred. Thirty-two patients were evaluated at the routine six week postoperative check-up. Four patients had had intercourse at that time and an adequate vagina was found in 21 other patients. It is concluded that this modification of Kun's technique, known as colocolponeopoiesis, has had, at short term in the majority of patients, functionally good results and an acceptable complication rate.

Impact of gas(less) laparoscopy and laparotomy on peritoneal tumor growth and abdominal wall metastases.

OBJECTIVE: A tumor model in the rat was used to study peritoneal tumor growth and abdominal wall metastases after carbon dioxide (CO2) pneumoperitoneum, gasless laparoscopy, and laparotomy. SUMMARY BACKGROUND DATA: The role of laparoscopic resection of cancer is under debate. Insufflation of the peritoneal cavity with CO2 is believed to be a causative factor in the development of abdominal wall metastases after laparoscopic resection of malignant tumors. METHODS: In the solid tumor model, a lump of 350-mg CC-531 tumor cells was placed intraperitoneally in rats having CO2 pneumoperitoneum (n = 8), gasless laparoscopy (n = 8), or conventional laparotomy (n = 8). After 20 minutes, the solid tumor was removed through a laparoscopic port or through the laparotomy. In the cell seeding model, 5 x 10(5) CC-531 cells were injected intraperitoneally before CO2 pneumoperitoneum (n = 12), gasless laparoscopy (n = 12), or laparotomy (n = 12). All operative procedures lasted 20 minutes. After 6 weeks, in the solid tumor model and after 4 weeks in the cell seeding model, tumor growth was scored semiquantitatively. All results were analyzed using the analysis of variance. RESULTS: In the solid tumor model, peritoneal tumor growth in the laparotomy group was greater than in the CO2 pneumoperitoneum group (p < 0.01). Peritoneal tumor growth in the CO2 group was greater than in the gasless group (p < 0.01). The size of abdominal wall metastases was greater at the port site of extraction of the tumor than at the other port sites (p < 0.001). In the cell seeding model, peritoneal tumor growth was greater after laparotomy in comparison to CO2 pneumoperitoneum (p < 0.02). Peritoneal tumor growth in the CO2 group was greater than in the gasless group (p < 0.01). The port site metastases in the CO2 group were greater than in the gasless group (p < 0.01). CONCLUSIONS: The following conclusions can be made: 1) that direct contact between solid tumor and the port site enhances local tumor growth, 2) that laparoscopy is associated with less intraperitoneal tumor growth than laparotomy, and 3) that insufflation of CO2 promotes tumor growth at the peritoneum and is associated with greater abdominal wall metastases than gasless laparoscopy.

Effect of fibrin sealant on the integrity of colonic anastomoses in rats with faecal peritonitis.

OBJECTIVE: To assess the influence of fibrin adhesive on the healing of colonic anastomoses in rats with and without faecal peritonitis. DESIGN: Controlled study. SETTING: Laboratory for experimental surgery, Erasmus University Rotterdam, The Netherlands. MATERIAL: 120 male Wag/Rij rats. INTERVENTIONS: All rats had a single layer end-to-end anastomosis fashioned with 7/0 polypropylene. Faecal peritonitis was then induced in half of the rats by placement of 200 mg powdered autoclaved rat faeces in the peritoneal cavity near the anastomosis. Rats were allocated to one of four groups (n = 30 in each): 1--control; 2--additional sealing with fibrin glue; 3--peritonitis alone; and 4--peritonitis with fibrin glue. MAIN OUTCOME MEASURES: Body weight, adhesion formation, anastomotic bursting pressure and collagen concentration around the anastomosis on days 2, 4, and 7 in 10 rats from each group. RESULTS: 11 rats died of peritonitis before the experiment was completed. Peritonitis caused increased formation of adhesions and abscesses, with or without fibrin sealant. Bursting pressure at the anastomosis was significantly reduced in peritonitis compared with controls on days 4 and 7, and this was not prevented by fibrin. Sealing of anastomoses resulted in lower bursting pressures on day 4 in control animals. Collagen concentration was significantly reduced in peritonitis with or without fibrin sealant on days 4 and 7, and after fibrin sealing of control anastomoses. CONCLUSION: Faecal peritonitis reduced mechanical strength and collagen concentration of colonic anastomoses, and this was not prevented by additional sealing of the anastomosis with fibrin sealant.

Bacterial flora of the sigmoid neovagina.

The bacterial microbiota of 15 sigmoid neovaginas, created in patients with congenital vaginal aplasia or male transsexualism, was studied. No specimen was sterile, and only normal inhabitants of the colon were cultured. The total counts of bacteria were lower than those reported for healthy sigmoid colons.

Effect of antibiotics in fibrin sealant on healing colonic anastomoses in the rat.

In 90 rats a colonic anastomosis was constructed with 12 interrupted 7/0 polypropylene sutures. Group 1 (n = 30) served as a control group. In group 2 (n = 30) the anastomosis was sealed with fibrin adhesive and in group 3 (n = 30) a mixture of fibrin, clindamycin and cefotaxime was used. On days 2, 4 and 7, ten animals in each group were killed. Adhesion formation was significantly increased in groups 2 and 3 compared with the control group. On day 2 the anastomosis was significantly stronger after sealing with antibiotic-fibrin mixture. On day 4 the bursting pressure in group 2 was significantly lower than in groups 1 and 3. At the same time the concentration of hydroxyproline was significantly reduced in group 2, but not in group 3. The addition of antibiotics prevents the negative effect of fibrin adhesive on the healing colonic anastomosis and contributes to a stronger anastomosis on day 2 after operation.