Hyaluronate Carboxymethylcellulose Research Articles

Hyaluronate carboxymethylcellulose sheets for the prevention of adhesive complications: a model-based cost-utility analysis.

Clinical trials suggest that hyaluronate carboxymethylcellulose (HA/CMC) prevents adhesion-related complications after intra-abdominal surgery, but at a high upfront cost. This study evaluated the cost-effectiveness of HA/CMC for patients undergoing curative-intent open colorectal cancer surgery. Using a Markov Monte Carlo microsimulation model, we conducted a cost-utility analysis comparing the cost-effectiveness of HA/CMC at curative-intent open colorectal cancer surgery versus standard management. We considered a scenario where HA/CMC was used at the index operation only, as well as where it was used at the index operation and any subsequent operations. The perspective was that of the third-party payer. Costs and utilities were discounted 1.5% annually, with a 1-month cycle length and 5-year time horizon. Model input data were obtained from a literature review. Outcomes included cost, quality-adjusted life-years (QALYs), small bowel obstructions (SBOs) and operations for SBO. Using HA/CMC at the index operation results in an incremental cost increase of CA$316 and provides 0.001 additional QALYs, for an incremental cost-effectiveness ratio of CA$310,000 per QALY compared to standard management. In our simulated cohort of 10,000 patients, HA/CMC prevented 460 SBOs and 293 surgeries for SBO. Probabilistic sensitivity analysis found that HA/CMC was cost-effective in 18.5% of iterations, at a cost-effectiveness threshold of CA$50,000 per QALY. Results of the scenario analysis where HA/CMC was used at the index operation and any subsequent operations were similar. Hyaluronate carboxymethylcellulose prevents adhesive bowel obstruction after open colorectal cancer surgery but is unlikely to be cost-effective given minimal long-term impact on healthcare costs and QALYs.

Focus on the Primary Prevention of Intrauterine Adhesions: Current Concept and Vision.

Intrauterine adhesion (IUA), and its severe form Asherman syndrome (Asherman’s syndrome), is a mysterious disease, often accompanied with severe clinical problems contributing to a significant impairment of reproductive function, such as menstrual disturbance (amenorrhea), infertility or recurrent pregnancy loss. Among these, its correlated infertility may be one of the most challenging problems. Although there are many etiologies for the development of IUA, uterine instrumentation is the main cause of IUA. Additionally, more complicated intrauterine surgeries can be performed by advanced technology, further increasing the risk of IUA. Strategies attempting to minimize the risk and reducing its severity are urgently needed. The current review will expand the level of our knowledge required to face the troublesome disease of IUA. It is separated into six sections, addressing the introduction of the normal cyclic endometrial repairing process and its abruption causing the formation of IUA; the etiology and prevalence of IUA; the diagnosis of IUA; the classification of IUA; the pathophysiology of IUA; and the primary prevention of IUA, including (1) delicate surgical techniques, such as the use of surgical instruments, energy systems, and pre-hysteroscopic management, (2) barrier methods, such as gels, intrauterine devices, intrauterine balloons, as well as membrane structures containing hyaluronate–carboxymethylcellulose or polyethylene oxide–sodium carboxymethylcellulose as anti-adhesive barrier.

Comparing Five New Polymer Barriers for the Prevention of Intra-abdominal Adhesions in a Rat Model

BackgroundIntra-abdominal adhesions affect up to 93% of the patients after abdominal surgery, causing small-bowel obstruction, infertility, chronic abdominal pain, and iatrogenic bowel injury at reoperation. The efficacy of five new polymer antiadhesive barriers to avoid adhesion formation is evaluated in an ischemic button model in rats. Materials and methodsFive new, biodegradable polyurethane and copolyester-based, antiadhesive barriers (A1, A2, A3, B1, and B2) were evaluated in separate experimental groups and compared with two control groups (hyaluronate carboxymethylcellulose barrier and no antiadhesive barrier) in an ischemic button model (n = 11 per group operated). After 14 d, the quantity and quality of the adhesions were scored macroscopically. The Kruskal–Wallis with Mann–Whitney U post hoc and the Fisher's exact tests were used for data analysis. The Bonferroni correction method was applied, and a P-value <0.007 was considered significant. ResultsTwo animals died during surgery and follow-up. A significant reduction of adhesions to ischemic buttons was found in the A2 group (median, 3.5; interquartile range, 2.25) compared with no adhesive barrier (median, 8.0; interquartile range, 2.0) (P = 0.001). The remaining groups did not differ significantly regarding adhesion quantity or quality. Adverse events were observed in the A2, A3, and B2 groups. ConclusionsThe A2 antiadhesive barrier reduced the adhesion formation significantly compared with no anti-adhesive barrier, but applicability is questionable because of extensive adverse events observed due to implantation of the anti-adhesive barrier. The Nair score appears not to be sensitive enough to detect differences in adhesion formation in this model. Future research should focus on anti-adhesive barriers that are self-adhering.

A Case of an Enterocutaneous Fistula Caused by Sodium Hyaluronate Carboxymethylcellulose Bioresorbable Membrane-induced Intestinal Adhesions

A Case of an Enterocutaneous Fistula Caused by Sodium Hyaluronate Carboxymethylcellulose Bioresorbable Membrane-induced Intestinal Adhesions

Prolonged pain reducing effect of sodium hyaluronate-carboxymethyl cellulose solution in the selective nerve root block (SNRB) of lumbar radiculopathy: a prospective, double-blind, randomized controlled clinical trial

The pattern of linear graph schematized by visual analogue scale (VAS) score displaying pain worsening between 2 days and 2 weeks after selective nerve root block (SNRB) is called rebound pain. The purpose of this study was to determine if sodium hyaluronate and carboxymethyl cellulose solution (HA-CMC sol) injection could reduce the occurrence of rebound pain at 3 days to 2 weeks after SNRB in patients with radiculopathy compared with injection with corticosteroids and local anesthetics alone. Double blinded randomized controlled clinical trial. A total of 44 patients (23 of 24 patients in the Guardix group and 21 of 24 patients in the control group) who finished the follow-up session were subjects of this study. Patients were asked to write down their average VAS pain scores daily for 12 weeks. Functional outcomes were assessed by Oswestry Disability Index, Roland Morris Disability Questionnaire , and Short Form-36. A cocktail of corticosteroids, 1% lidocaine, 0.5% Bupivacaine, and 1 mL of normal saline was used for the control group whereas a cocktail of corticosteroids, 1% lidocaine, 0.5% Bupivacaine, and 1 mL of HA-CMC solution was used for the G group. Study participants were randomized into one of two treatment regimens. They were followed up for 3 months. VAS score at 2 weeks after the procedure was 4.19±1.32 in the control group, which was significantly (p<.05) higher than that (2.43±1.24) in the G group. VAS score at 6 weeks after the procedure was 4.00±1.23 in the control group and 3.22±1.45 in the G group, showing no significant (p=.077) difference between the two groups. There were no significant differences in functional outcomes at 6 or 12 weeks after the procedure. Compared with conventional cocktail used for SNRB, addition of HA-CMC sol showed effective control of rebound pain at 3 days to 2 weeks after the procedure.

Effects of hyaluronate-carboxymethylcellulose membranes on the clinical outcome of horses undergoing emergency exploratory celiotomy.

To determine the influence of hyaluronate-carboxymethylcellulose (HA-CMC) membranes applied to intestinal anastomoses or enterotomies on postoperative complications after emergency exploratory celiotomy. Multicenter retrospective case-controlled series. Adult horses (59 in the HA-CMC group and 91 controls). Medical records from 4 referral hospitals were searched for horses ≥1 year of age, treated between 2008 and 2014 with emergency exploratory celiotomy, and surviving at least 24 hours postoperatively. Horses receiving repeat celiotomy during the same hospitalization were excluded. Horses who received HA-CMC were matched with controls who did not receive HA-CMC but had similar intestinal lesions and procedures at the same referral hospital. Postoperative complications (colic, nasogastric reflux, fever, incisional infection, and septic peritonitis), duration of hospitalization, and survival were compared between groups. Data were compared between horses by t test, Wilcoxon signed rank test, and χ2 test. The volume of nasogastric reflux at admission (P = .02) and the duration of administration of lidocaine after surgery (P = .02) were greater in horses with HA-CMC membranes than in controls. No difference in postoperative complications or survival was detected between groups: 48 of 59 (81%) horses treated with HA-CMC survived until discharge from the hospital compared with 80 of 91 (88%) horses in the control group (P = .27). Fifteen of 21 horses treated with HA-CMC and 30 of 43 horses in the control group survived >12 months after hospital discharge. Application of HA-CMC membranes to anastomoses or intestinal incisions did not influence postoperative complications or survival after emergency celiotomy compared with controls. The safety and efficacy of HA-CMC membrane application to intestinal sites during colic surgery in horses is equivocal.

Safety and Efficacy of Alginate Adhesion Barrier Gel in Compromised Intestinal Anastomosis.

For any anti-adhesive barrier developed for abdominal surgery, the use under conditions in which anastomotic healing is compromised needs to be investigated. The current study evaluates the effect of a new ultrapure alginate gel on early healing of high-risk anastomoses in the ileum and compares this with the gold standard used in clinical practice. In 75 adult male Wistar rats, a 5 mm ileal segment was resected and continuity was restored by construction of an inverted anastomosis. Rats were divided randomly into a control group and groups receiving either alginate gel or a sodium hyaluronate carboxymethylcellulose (HA/CMC) film around the anastomosis (n = 25 each). Carprofen, given in a daily dose of 1.25 mg/kg, was used to compromise anastomotic healing. At day three, animals were killed and scored for signs of anastomotic leakage and the presence of adhesions. The incidence of adhesion formation was 95% in the HA/CMC film group, which was significantly higher than in the controls (64%, p = 0.010) and the alginate gel group (52%, p = 0.004). The adhesion score was nearly 40% lower in the alginate gel group compared with the HA/CMC film group. The incidence of ileal leakage in the HA/CMC film group (92%) was significantly higher than in the controls (68%, p = 0.016). Leakage rate did not differ between the alginate gel and control groups. There was no significant difference between groups in either incision bursting pressure or incision breaking strength. Ultrapure alginate gel does not interfere with repair of ileal anastomoses constructed under conditions in which chances of anastomotic dehiscence are high. The alginate gel performs better than the HA/CMC film.

Meta-Analysis of the Effects of Adhesion Barriers on Adhesion Formation in the Horse.

To determine the efficacy of adhesion barriers in horses using quantitative statistical analysis. Meta-analytical review. A search using PubMed/MEDLINE and Google Scholar was performed, followed by secondary searches of veterinary trade journals, bibliographies of relevant articles, manufacturer websites, and technical reference guides. Randomized experimental trials in healthy horses were considered that included both a treatment and control group. The endpoint required was euthanasia or laparoscopy to identify adhesion formation. A meta-analysis was performed using a random effects model, with the effect size calculated as an odds ratio (OR) with 95% confidence intervals (CI). Statistical significance was set at P<.05. Out of 354 peer reviewed publications that met the search criteria, a total of 9 relevant studies were identified and investigated the use of sodium carboxymethylcellulose (CMC) solutions, sodium hyaluronate/carboxymethylcellulose (HA/CMC) membranes, hyaluronate (HA), and fucoidan solutions. The odds of adhesions in horses treated with an adhesion barrier were significantly lower than untreated controls (OR=0.102; 95% CI [0.041, 0.254]; P<.001). When analyzed as subsets for each type of barrier, horses treated with HA/CMC membranes and CMC solutions had significant OR for fewer adhesions (OR=0.061; 95% CI [0.013, 0.292]; OR=0.119; 95% CI [0.034, 0.415], respectively; P<.001). The meta-analysis demonstrated adhesion barriers provide a positive effect on the odds of adhesion formation. These results are tempered by the limitations of the study, including the small sample size and a bias towards publication of studies with only positive findings.

Regeneration of peritoneal mesothelial cells after placement of hyaluronate carboxymethyl-cellulose (Seprafilm®).

To examine the regeneration of mesothelium under a bioresorbable membrane. A 1cm2 piece of peritoneum was resected from both sides of the abdominal wall of retired female mice. A piece of hyaluronate and carboxymethyl-cellulose (Seprafilm®) was placed over the wound on one side and the other side was left uncovered. We evaluated the degree of adhesion and regeneration of mesothelial cells macroscopically and histologically using immunohistochemistry at different times. Macroscopically, the degree of postoperative adhesion in the treated site was significantly less than that in the untreated site. The membrane was left in place for 7 postoperative days (PODs). By POD 5, the regenerated peritoneum mesothelial cells covered part of the area and by POD 7, they had regenerated over almost all of that area in the abdominal wall. The anti-adhesion membrane worked as a physical barrier to prevent postoperative adhesion until the mesothelial cells had regenerated completely. To our knowledge, this is the first study conducted to assess the regeneration of peritoneum mesothelial cells under a bioresorbable membrane using immunohistochemistry.

A new poly(1,3-trimethylene carbonate) film provides effective adhesion reduction after major abdominal surgery in a rat model

Postoperative adhesions remain a major clinical problem after abdominal surgery. We evaluated the efficacy of a new poly(trimethylene carbonate) (PTMC) film as an antiadhesive material. In many abdominal operations, there is an increased risk of fecal contamination; the risk of (increased) infection in presence of PTMC film was studied in 2 additional animal models. A validated rat adhesion model with peritoneal ischemic buttons was used to compare the new PTMC film with a hyaluronate carboxymethylcellulose (HA-CMC) sheet, icodextrin solution, and a control group. Primary endpoint was occurrence of adhesions at the ischemic buttons after 14 days in 44 rats (n = 11 per group). To evaluate potential risks associated with the film, both an anastomotic leakage model and a cecal ligation and puncture model were used. Kruskal-Wallis tests with subsequent Mann-Whitney tests were used to detect differences between groups. PTMC film showed a significant reduction in the amount of adhesions (median, 0.5 buttons) compared with control group (median, 4 buttons; P < .001) and icodextrin group (median, 4.5; P < .001). The amount of adhesions was similar to the HA-CMC group (median, 2; P = .04). The presence of the film did not increase the risk of anastomotic leakage or bacterial growth in a contaminated environment. The presence of a PTMC film leads to a significant reduction in the amount of adhesions after 14 days in an ischemic button rat model. Furthermore, this film was found to be safe in an animal model, even in complex abdominal operations with an increased risk of fecal contamination.

Use of Antifibrotics to Prevent Ventriculoperitoneal Shunt Complications Due to Intra-abdominal Fibrosis: Experimental Study in a Rat Model.

Cerebrospinal fluid shunt operations have reduced the morbidity and mortality of hydrocephalus, but have potential complications. Ventriculoperitoneal (vp) shunt obstruction is one of the common complications of shunt surgery. The obstruction is caused by fibrosis and is usually located on the tip of the ventricular and/or peritoneal catheter. In our study, we aimed to demonstrate the known antifibrotic effects of heparin, hyaluronate/carboxymethylcellulose, and icodextrin on peritoneal catheter obstruction in a vp shunt model in rats. Thirty-two male Sprague-Dawley rats were used in this study. A shunt catheter was placed in the abdominal cavity. In the control group, isotonic solution, in the study groups, heparin, sodium hyaluronate/carboxymethylcellulose (HA/CMC), and icodextrin were intraperitoneally applied. The severity of adhesions and inflammation around the peritoneal catheter was evaluated after the rats were killed on day 30. One animal in the heparin group died due to intra-abdominal hemorrhage. We found the most adhesions in the control group. All three drugs (heparin, HA/CMC, icodextrin) were effective for adhesion prevention. HA/CMC was more effective than heparin, and icodextrin was most effective. There was a statistically significant difference between the icodextrin and the control group (p = 0.007). The intra-abdominal instillation of icodextrin, HA/CMC, and heparin, especially icodextrin, can decrease the rate of vp shunt dysfunction by preventing formation of intraperitoneal fibrosis.

Role of anti-adhesive barriers following rotator cuff repair surgery: an experimental study.

This experimental study investigates the effectiveness of expanded polytetrafluoroethylene (Dualmesh®, Gore Medical, Flagstaff, AZ, USA), sodium hyaluronate-carboxymethyl cellulose (Seprafilm®, Genzyme, Cambridge, MA, USA), and polysiloxane (silicone) as anti-adhesive barriers for inhibition of fibrosis in the subacromial area following rotator cuff repair. Rabbit rotator cuff tenotomy and repair was conducted on 24 rabbits in 4 groups: control (Group A), Dualmesh® (Group B), Seprafilm® (Group C), and silicone (Group D). Anti-adhesive barrier materials were sutured over the repaired rotator cuff. Macroscopic and histological evaluations were made at the end of the sixth postoperative week. Macroscopic evaluation revealed that minimal adhesion occurred in the control and silicone groups, while the Seprafilm® and Dualmesh® groups showed evidence of fibrosis. Microscopic evaluation revealed diffuse fibrosis and collagen accumulation in the Dualmesh® and Seprafilm® groups, whereas minimal collagen deposition and inflammatory cell reaction was found among the silicone and control groups. Significant differences were found between the silicone and Dualmesh® (p=0.001) and silicone and Seprafilm® groups (p=0.002), as well as between the control and Dualmesh® (p=0.002) and control and Seprafilm® groups (p=0.002). Expanded polytetrafluoroethylene (ePTFE/Dualmesh®) and sodium hyaluronate carboxymethyl cellulose (SH-CMC/Seprafilm®) did not prevent or attenuate postoperative subacromial fibrosis following cuff tear repair. Nor did silicone prevent or attenuate fibrosis. More detailed research is needed for development of an effective anti-adhesive barrier for use after rotator cuff tear surgery.

Analysis of oncologic outcomes associated with anti-adhesion sodium hyaluronate–carboxymethylcellulose (HA–CMC) barrier following optimal or complete cytoreductive surgery for ovarian, fallopian tube, and peritoneal cancers

Author(s): Krill, Lauren | Advisor(s): Kaplan, Sherrie | Abstract: Objectives: Hyaluronan is a component of the anti-adhesive barrier HA-CMC and has been implicated in tumor growth and metastasis. The study aim was to determine if HA-CMC use is associated with adverse effects on disease progression or survival in patients undergoing surgical cytoreduction for primary treatment of advanced ovarian, fallopian tube, and peritoneal cancers. Methods: Retrospective cohort study of patients undergoing optimal or complete cytoreduction between 1/95-12/08. The primary endpoints were progression free survival (PFS) and overall survival (OS). Fisher's exact test, Kaplan Meier survival analysis, and multivariate Cox proportional hazards regression were utilized. Results: Two hundred eighty-eight cases were analyzed; HA-CMC was utilized in 130 procedures (45%). On univariate analysis, HA-CMC was associated with complete cytoreduction, high surgical complexity score, good performance-status, and being alive at last follow-up (all pl0.01). Neither PFS nor OS was significantly different between subjects with or without HA-CMC (median PFS 16.8 vs 16.4 months, p=0.36; median OS 40.6 vs 36 months, P=0.33). PFS was significantly shorter amongst high-risk subjects, independent of HA-CMC use, with age g50, Stage IV disease, PS g1, visible residual disease, or interval cytoreduction (all pl0.05). Additionally, major postoperative complications and platinum resistance were associated with shorter OS (pl0.05). After controlling for confounding factors using multivariate Cox proportional hazards regression, HA-CMC use did not independently predict PFS (HR 1.1; 95% CI:0.83-1.45) or OS (HR 0.98; 95% CI:0.73-1.32). Conclusions: HA-CMC adhesion barrier placement at the time of primary or interval cytoreductive surgery for ovarian, fallopian tube, and peritoneal cancer does not impact recurrence or survival outcomes.

Ultrapure alginate anti-adhesion gel does not impair colon anastomotic strength

BackgroundUltrapure alginate gel is promising in terms of adhesion prevention. Because anti-adhesive barriers have been shown to disturb healing of bowel anastomoses, the effect of ultrapure alginate gel on the repair of colon anastomoses was studied. Materials and methodsIn 102 male Wistar rats, a 0.5-cm segment was resected from the descending colon and continuity was restored by an inverted single-layer end-to-end anastomosis. Animals were randomized into a control, an alginate gel, and a sodium hyaluronate carboxymethyl cellulose film group, each n = 34. Half of each group was sacrificed at day 3 and 7 postoperatively. Anastomotic strength was assessed by measuring both bursting pressure and breaking strength. Hydroxyproline content was measured and histologic analysis was performed. The incidence of adhesion and abscess formation was scored at sacrifice. ResultsNo difference in either anastomotic-bursting pressure or breaking strength was found between experimental groups and the controls at any time point. Both the incidence of adhesion formation (35% versus 71%, P = 0.007) and the adhesion score (0.38 versus 0.79, P = 0.009) were significantly lower in the alginate gel group than in the controls. The abscess rate was higher (46% versus 18%, P = 0.030) in the hyaluronate carboxymethyl cellulose group than in the controls and unchanged in the alginate gel group. ConclusionsWhile reducing adhesion formation, ultrapure alginate gel does not interfere with the development of colonic anastomotic strength during the crucial early healing period.

Tranexamic acid and hyaluronate/carboxymethylcellulose create cell injury.

Background and Objectives:Postoperative pelvic adhesions are associated with chronic pelvic pain, dyspareunia, and infertility. The aim of this study was to evaluate the adhesion prevention effects of tranexamic acid (TA) and hyaluronate/carboxymethylcellulose (HA/CMC) barrier in the rat uterine horn models on the basis of macroscopic and microscopic adhesion scores and histopathological as well as biochemical parameters of inflammation.Methods:Twenty-one Wistar rats were randomly divided into 3 groups. Ten lesions were created on the antimesenteric surface of both uterine horns by bipolar cautery. Three milliliters of 0.9% sodium chloride solution were administered in the control group. A single layer of 2 × 2 cm HA/CMC was plated in group 2. Two milliliters of TA was applied in the last group. All rats were sacrificed at postoperative day 21.Results:No significant difference was found among the control group, the HA/CMC group, and the TA group in terms of macro-adhesion score (P = .206) and microadhesion score (P = .056). No significant difference was found among the 3 groups in terms of inflammation score (P = .815) and inflammatory cell activity (P = .835). Malondialdehyde levels were significantly lower in the control group than in the TA group and HA/CMC group (P = .028). Superoxide dismutase and glutathione S-transferase activities were found to be higher in the control group than in the TA group (P = .005) and HA/CMC group (P = .009).Conclusions:TA and HA/CMC had no efficacy in preventing macroscopic or microscopic adhesion formation and decreasing inflammatory cell activity or inflammation score in our rat models. TA and HA/CMC increased the levels of free radicals and reduced the activities of superoxide dismutase and glutathione S-transferase enzymes, which act to reduce tissue injury.

Benefits and harms of adhesion barriers for abdominal surgery: a systematic review and meta-analysis

Formation of adhesions after peritoneal surgery results in high morbidity. Barriers to prevent adhesion are seldom applied, despite their ability to reduce the severity of adhesion formation. We evaluated the benefits and harms of four adhesion barriers that have been approved for clinical use. In this systematic review and meta-analysis, we searched PubMed, CENTRAL, and Embase for randomised clinical trials assessing use of oxidised regenerated cellulose, hyaluronate carboxymethylcellulose, icodextrin, or polyethylene glycol in abdominal surgery. Two researchers independently identified reports and extracted data. We compared use of a barrier with no barrier for nine predefined outcomes, graded for clinical relevance. The primary outcome was reoperation for adhesive small bowel obstruction. We assessed systematic error, random error, and design error with the error matrix approach. This study is registered with PROSPERO, number CRD42012003321. Our search returned 1840 results, from which 28 trials (5191 patients) were included in our meta-analysis. The risks of systematic and random errors were low. No trials reported data for the effect of oxidised regenerated cellulose or polyethylene glycol on reoperations for adhesive small bowel obstruction. Oxidised regenerated cellulose reduced the incidence of adhesions (relative risk [RR] 0·51, 95% CI 0·31-0·86). Some evidence suggests that hyaluronate carboxymethylcellulose reduces the incidence of reoperations for adhesive small bowel obstruction (RR 0·49, 95% CI 0·28-0·88). For icodextrin, reoperation for adhesive small bowel obstruction did not differ significantly between groups (RR 0·33, 95% CI 0·03-3·11). No barriers were associated with an increase in serious adverse events. Oxidised regenerated cellulose and hyaluronate carboxymethylcellulose can safely reduce clinically relevant consequences of adhesions. None.

Oncologic Outcome With Use of Sodium Hyaluronate–Carboxymethylcellulose Barrier in Gastric Cancer

Hyaluronan is a component of an anti-adhesive barrier and has been implicated in tumor growth and metastasis. We aimed to determine whether this anti-adhesive barrier was associated with rates of postoperative complications and duration of survival in patients with gastric cancer. We identified 415 consecutive patients with gastric cancer who underwent gastrectomy. Information about patients' demographics, medical history, surgical procedures, postoperative complications, disease stage, histology, and survival was collected from medical records. One hundred and ninety-six patients received intraoperative placement of an anti-adhesive barrier composed of hyaluronan-carboxymethylcellulose (HA-CMC) (HA-CMC group), and 219 did not (control group). The incidence of postoperative complications was significantly increased in the control group (22.8%) compared with the HA-CMC group (13.3%). However, there was no significant difference in overall survival between the HA-CMC and control groups. Our study suggests that the anti-adhesive barrier does not affect oncologic outcome, nor does it increase postoperative complications in patients undergoing surgery for gastric cancer.

Preventing intra-abdominal adhesions with a sodium hyaluronate carboxymethylcellulose membrane enabled visualization of hepatic microcirculation

We aimed to evaluate whether using sodium hyaluronate carboxymethylcellulose membrane (Seprafilm™) can facilitate assessment of hepatic microcirculation via orthogonal polarization spectroscopy (OPS) by preventing intra-abdominal adhesions and whether Seprafilm™ as a foreign material can evoke local or systemic inflammatory reactions. After the right median hepatic vein was ligated, rats received either placement of Seprafilm™ or untreated with observation of 1 or 4 weeks (n = 6/group). Hepatic microcirculation was visualized. Systemic and local inflammatory reactions were evaluated by blood count, histology and immunohistochemical staining for CD68. Seprafilm™ significantly (P < 0.05) prevented intra-abdominal adhesion formation compared to non-Seprafilm™ groups (adhesion score: 0 vs 1.3 ± 0.5 at POW1 and 0.3 ± 0.5 vs 3.5 ± 1.4 at POW4). Placement of Seprafilm™ provided sufficient liver surface for acquisition of OPS videos during the harvest procedure. Adhesiolysis in non-Seprafilm™ groups prevented visualization of hepatic microcirculation. A severe local foreign body reaction with formation of a “fibrin-like” membrane containing CD68-positive inflammatory histiocytic cells and mesothelial cells was observed in Seprafilm™ groups even at POW4. Use of Seprafilm™ conferred visualization of hepatic microcirculation after long term observation in experimental setting. In clinical situation, we would suggest being very cautious in immuno-compromised patients because of an ongoing local foreign body reaction caused by Seprafilm™.

Prevention of postsurgical adhesions using an ultrapure alginate-based gel

Postoperative adhesion formation is a common consequence of abdominal surgery, and constitutes a major source of morbidity and mortality. This study evaluated an ultrapure alginate-based antiadhesive barrier gel. Experiments were performed in a rat model with caecal abrasion and peritoneal side wall excision. The primary endpoint was the incidence of adhesions at 14 days after surgery. In experiment 1 (24 rats), animals treated with alginate gel were compared with controls that had no antiadhesive barrier. In experiment 2 (42 rats), alginate gel was compared with sodium hyaluronate carboxymethyl cellulose (HA/CMC) membrane and with no antiadhesive barrier. To check for any remote action of the gel, in experiment 3 (45 rats) application of alginate gel to the ipsilateral versus contralateral side of injury was compared with no antiadhesive barrier. In experiment 1, ultrapure alginate gel reduced the incidence of adhesions from eight of 12 in control animals to one in 12 (P = 0·009). Tissue healing assessed by histology was similar in both groups. In experiment 2, ultrapure alginate gel and HA/CMC membrane showed similar antiadhesive effectiveness, reducing the incidence of adhesions from ten of 14 rats in the control group to three of 14 (P = 0·021) and two of 14 (P = 0·006) respectively. In experiment 3, ultrapure alginate gel reduced the incidence of adhesions at the site of direct application (1 of 15) compared with controls (13 of 15; P = 0·001), but not if applied remotely (9 of 15; P = 0·214). Ultrapure alginate gel decreased the incidence of postoperative adhesion formation in this rat model.

All the commercially available adhesion barriers have the same effect on adhesion prophylaxis?; A comparison of barrier agents using a newly developed, severe intra-abdominal adhesion model

Various types of adhesion barriers are widely used to prevent intra-abdominal adhesion. However, few studies have compared the efficacy of adhesion barriers using the same animal model. The aim of this study was to compare the anti-adhesive effects of various barrier agents using a newly developed, severe adhesion model. A severe adhesion model was established by excision of a 1-cm(2) intra-abdominal wall and application of cyanoacrylate in rat. Eighty male Sprague-Dawley rats (10 weeks old; 370 ± 50 g) were divided randomly into four groups (n = 20 each): the untreated control group, G-group using a hyaluronic acid and sodium carboxymethyl cellulose gel (Guardix-sol®), A-group using 4% icodextrin (Adept®), and S-group using a hyaluronate-carboxymethyl cellulose membrane (Seprafilm®). The effect of each adhesion barrier was evaluated by means of the extent and severity of adhesion, difficulty of adhesiolysis scoring systems, and microscopic grade of fibrosis. The G-group showed no difference in adhesion score and fibrosis, the A-group demonstrated only a significantly lower fibrosis, and the S-group exhibited a significantly lower adhesion score and lower fibrosis compared with the control group. The S-group had a significantly lower adhesion score and reduced fibrosis compared with the G-group; however, no significant difference in adhesion score and fibrosis was noted with the A-group. The membranous barrier Seprafilm® may be effective in the prevention of adhesion in the condition of peritoneal injury combined with foreign material. Adept® showed a tendency of decreasing the severity of adhesion and was effective in the prevention of fibrosis.