D-limonene inhibits peritoneal adhesion formation in rats via anti-inflammatory, anti-angiogenic, and antioxidative effects

The aim of this research was to investigate the effects of D-limonene on decreasing post-operative adhesion in rats and to understand the mechanisms involved. Peritoneal adhesions were induced by creating different incisions and excising a 1 × 1 cm section of the peritoneum. The experimental groups included a sham group, a control group in which peritoneal adhesions were induced without any treatment, and two treatment groups in which animals received D-limonene with dosages of 25 and 50 mg/kg after inducing peritoneal adhesions. Macroscopic examination of adhesions showed that both treatment groups had reduced adhesion bands in comparison to the control group. Immunohistochemical assessment of TGF-β1, TNF-α, and VEGF on day 14 revealed a significant increment in the level of immunopositive cells for the mentioned markers in the control group, whereas administration of limonene in both doses significantly reduced levels of TGF-β1, TNF-α, and VEGF (P < 0.05). Induction of peritoneal adhesions in the control group significantly increased TGF-β1, TNF-α, and VEGF on days 3 and 14 in western blot evaluation, while treatment with limonene significantly reduced TNF-α level on day 14 (P < 0.05). Moreover, VEGF levels in both treatment groups significantly reduced on days 3 and 14. In the control group, a significant increment in the levels of MDA and NO and a notable decline in the levels of GPX, CAT was observed (P < 0.05). Limonene 50 group significantly reduced MDA level and increased GPx and CAT levels on day 14 (P < 0.05). In summary, D-limonene reduced adhesion bands, inflammatory cytokines, angiogenesis, and oxidative stress.

Preparation of healing promotive alanyl-glutamine-poly(p-dioxanone) electrospun membrane integrated with gentamycin and its application for intestinal anastomosis in rats

Anastomosis surgery at the intestinal site is performed on millions of individuals every year. However, several persistent complications, such as anastomotic leakage, abnormal adhesion, and anastomotic stenosis, have been observed after the surgery. For promoting anastomotic healing and to overcome the challenges mentioned above, re-epithelialization at anastomotic sites is crucial. In this study, an epithelialization-promoting macromolecular prodrug Ala-Gln-PPDO was prepared and processed into fibrous membranes by electrospinning. Ala-Gln and gentamicin were sustainably released from the electrospun membranes with degradation of these membranes to promote the proliferation of rat intestinal epithelial cells and suppress the proliferation of Staphylococcus aureus and Escherichia coli. The comprehensive repair effects of Ala-Gln-PPDO membranes have been evaluated in rat models of intestinal anastomosis in this study. Application of Ala-Gln-PPDO membranes, especially the gentamicin-incorporated Ala-Gln-PPDO ones, could prevent adhesion between the injured intestine and surrounding intestinal tissues. In addition, they did not affect the healing strength of anastomotic stoma negatively and could promote re-epithelialization at the anastomotic sites. Furthermore, the gentamicin-incorporated Ala-Gln-PPDO membranes could relieve stenosis at anastomotic sites. The gentamicin-incorporated Ala-Gln-PPDO electrospun membrane is a promising, comprehensive implantable material for promoting healing after gastrointestinal anastomosis owing to its effects involving the promotion of re-epithelialization, prevention of adhesion, and relieving of anastomotic stenosis.

Biomimetic hybrid hydrogel for hemostasis, adhesion prevention and promoting regeneration after partial liver resection

Partial liver resection is an established treatment for hepatic disorders. However, surgical bleeding, intra-abdominal adhesion and rapid liver regeneration are still major challenges after partial liver resection, associated with morbidity and mortality. Herein, a biomimetic hybrid hydrogel, composed of oxidized hyaluronic acid, glycol chitosan and MenSCs-derived conditioned medium (CM), is presented to address these issues. The hybrid hydrogel is formed through reversible Schiff base, and possesses injectability and self-healing capability. Moreover, hybrid hydrogel exhibits the capabilities of hemostasis, anti-infection, tissue adhesion and controllable release of cargoes. Based on in vivo studies of the multifunctional hybrid hydrogel, it is demonstrated that acute bleeding in partial liver resection can be ceased immediately by virtue of the hemostasis features of hybrid hydrogel. Also, a significant reduction of intra-abdominal adhesion is confirmed in hybrid hydrogel-treated resection surface. Furthermore, upon the treatment of hybrid hydrogel, hepatic cell proliferation and tissue regeneration can be significantly improved due to the controllably released cytokines from MenSCs-derived CM, exerting the effects of mitogenesis and anti-inflammation in vivo. Thus, the biomimetic hybrid hydrogel can be a promising candidate with great potential for application in partial liver resection.

A biomimetic triple-layered biocomposite with effective multifunction for dura repair

Dura mater defect and subsequent cerebrospinal fluid (CSF) leakage usually appear in trauma or neurosurgical procedures and are followed by a series of serious complications and even death. The use of a qualified dura mater substitute with multifunction of leakage blockade, adhesion prevention, and dura reconstruction is one of the promising treatment methods. However, even though some products have been used in the clinic, none of the substitutes achieved the required multifunction. In this study, we aimed to design and fabricate a dura repair composite with the ideal multifunction. By biomimicking the structure and component of natural dura, we applied poly(L-lactic acid) (PLLA), chitosan (CS), gelatin, and acellular small intestinal submucosa (SIS) powders to successfully prepare a triple-layered composite. Then, a series of specific devices and techniques were developed to investigate the performance. The results revealed that satisfactory structural stability could be realized under good synergistic interactions among the components. In addition, all the findings suggested that the bionic triple-layered composite showed satisfactory multifunction of leakage blockade, adhesion prevention, antibacterial property, and dura reconstruction potential, and thus, it might be a promising candidate for dura repair. STATEMENT OF SIGNIFICANCE: Developing qualified dura mater substitutes with multifunction of leakage blockade, adhesion prevention, and dura reconstruction is crucial for treating dura mater defect and subsequent cerebrospinal fluid (CSF) leakage that appear in trauma or neurosurgical procedures. In this study, we designed and fabricated a triple-layered dura repair biocomposite with satisfactory structural stability and desired multifunction based on biomimicking of the structure and component of natural dura. Moreover, a series of specific devices and techniques were developed to investigate the relevant performance. Overall, the developed hydrogel electrospinning system exhibited excellent advantages in achieving multifunction and could be applied widely in the future to achieve multifunctional tissue repair materials.

Dual dynamically crosslinked thermosensitive hydrogel with self-fixing as a postoperative anti-adhesion barrier

Tissue adhesion is a severe postoperative complication. Various strategies have been developed to minimize postoperative adhesion, but the clinical efficacy is still far from satisfactory. Herein, we present a dual dynamically crosslinked hydrogel to serve as a physical postoperative anti-adhesion barrier. The hydrogel was generated by dynamic chemical oxime bonding from alkoxyamine-terminated Pluronic F127 (AOP127) and oxidized hyaluronic acid (OHA), as well as hydrophobic association of AOP127. Rheological analysis demonstrated that the hydrogel exhibits temperature sensitivity. At 37 °C, it shows much higher modulus and higher stability than the Pluronic F127 hydrogel. Hemolytic assays suggested that the hydrogel undergoes low hemolysis. In addition, it exhibited anti-adhesion to blood cells in blood cell adhesion tests. It also showed an anti-attachment effect to fibroblasts and biocompatibility in vitro cell studies. Macroscopic evaluation and lap-shear tests revealed that the hydrogel has a moderate adhesive capacity to tissue, which is important for self-fixation. A rat model of sidewall defect-bowel abrasion was established to evaluate the anti-adhesion effect in vivo. The gross observation and pathological analysis revealed a significant reduction in postoperative peritoneal adhesion in the AOP127/OHA hydrogel-treated group than those treated with normal saline or Pluronic F127 hydrogel. Hence, the dual dynamically crosslinked hydrogel with self-fixable capacity may be suitable as a physical barrier for postoperative adhesion prevention. STATEMENT OF SIGNIFICANCE: Despite the development of numerous postoperative anti-adhesion barriers, their anti-adhesion efficacy is still limited in clinical trials due to poor tissue adhesion and rapid clearance from injured areas. Herein, we have developed a dual dynamic crosslinked hydrogel, generated by dynamic oxime bonds and hydrophobic interactions. The hydrogel is temperature-sensitive and demonstrates moderate tissue adhesion capacity, which allows for self-fixation when applied to defects. The introduction of dynamic covalent bonds improves the stability of the hydrogel. Moreover, the hydrogel not only displays appropriate hemocompatibility, cytocompatibility and anti-adhesion of blood cells and fibroblasts, but it also effectively contributes to preventing postoperative peritoneal adhesions in vivo. Hence, this dual dynamic crosslinked hydrogel may have potential applications as a physical barrier in clinical practice.

Safe and easy technique for the laparoscopic application of Seprafilm® in gynecologic surgery

INTRODUCTION

Laparoscopic surgery is a minimally invasive surgery, and the rate of postoperative adhesions is low. Although Seprafilm® helps to reduce adhesions, its application in the abdominal cavity during laparoscopic surgery is difficult because of its material. Therefore, we propose an easy method for applying this adhesion barrier.

MATERIALS AND SURGICAL TECHNIQUE

The Seprafilm is cut into four equal pieces. The four pieces are stacked, firmly folded twice, and grasped with the forceps. The reducer sleeve is slid over the bundle of Seprafilm. The forceps with the reducer sleeve is inserted through a 12-mm trocar near the target area. The reducer sleeve is then slid down the forceps to uncover the Seprafilm. Finally, each piece of Seprafilm is applied over the suture area. In all cases, the Seprafilm was successfully applied to the intended target. There were no cases in which Seprafilm was incompletely applied or in which it could not be used because of moistening. The average application times of surgeon 1 and surgeon 2 were 4.8 min and 5.0 min, respectively; this difference was not significant. There were no postoperative complications in any case.

DISCUSSION

It is safe and easy to use our simple technique to apply Seprafilm adhesion barrier laparoscopically. Further studies are warranted to prove Seprafilm's efficacy after such application.

Comparison of adhesion prevention capabilities of the modified starch powder-based medical devices 4DryField® PH and Arista™ AH in the Optimized Peritoneal Adhesion Model

Adhesion barriers can be based on numerous substances. In the rat Optimized Peritoneal Adhesion Model (OPAM) the starch-based hemostats 4DryField and Arista were tested for their capability to act in a preventive manner against adhesion formation (applied as a powder that was mixed in situ with saline solution to form a barrier gel). Adhesions were scored using the established scoring systems by Lauder and Hoffmann, as well as histopathologically using the score by Zühlke. Animals receiving saline solution were used as controls. As previously published, 4DryField reduced peritoneal adhesions significantly. However, Arista did not lead to a statistically significant reduction of adhesion formation. When comparing 4DryField and Arista applied in the same manner, only 4DryField was significantly effective in preventing peritoneal adhesions. Histopathological evaluations confirmed the results of the macroscopic investigation, leading to the conclusion that starch-based hemostats do not generally have the capability to function as effective adhesion prevention devices.

Crystalloid fluid suspension results in decreased adhesion burden when compared to bioresorbable membranes in a rat model

INTRODUCTION

Adhesion formation represents a major cause of long-term morbidity. Suspension of intra-abdominal contents in fluid medium may effectively prevent adhesion formation. We compare saline hydro-flotation (NS) to hyaluronate bioresorbable membranes (HBM) for adhesion prevention following surgery.

METHODS

Animals were randomized to four groups: sham (no injury, n = 5), control (injury without intervention, n = 5), HBM (n = 20) or 10 cc NS (n = 21). Interventions were administered after standardized surgical trauma to the cecum and abdominal wall. Necropsies at two weeks were completed to compare adhesion burden using a customary scoring algorithm.

RESULTS

Significant adhesion burden was noted in all rats. HBM sustained a more significant adhesion burden with higher total adhesion scores (HBM = 10 vs NS = 8.1/15, p = 0.02). Gross adhesion scores were lower with NS (5.6/9) compared to HBM (7.1/9, p = 0.01). Neo-vascularity was more common in HBM at 2.6/3 versus 1.9/3 with NS (p = 0.01). Percent of the cecum encased with adhesion was higher with HBM (42%) compared to NS (31%, p = 0.05).

DISCUSSION

Fluid based anti-adhesion methods should be considered for abdominal adhesion formation prevention.

Biodegradable and injectable thermoreversible xyloglucan based hydrogel for prevention of postoperative adhesion

Peritoneal adhesion is very common after abdominal and pelvic surgery, which leads to a variety of severe complications. Although numerous pharmacological treatments and barrier-based devices have been investigated to minimize or prevent postoperative adhesion, the clinical efficacy is not very encouraging. In this work, a biodegradable and thermoreversible galactose modified xyloglucan (mXG) hydrogel was developed and the efficacy of mXG hydrogel in preventing postoperative peritoneal adhesion was investigated. The 4% (w/v) mXG solution was a free flowing sol at low temperature, but could rapidly convert into a physical hydrogel at body temperature without any extra additives or chemical reactions. In vitro cell tests showed that mXG hydrogel was non-toxic and could effectively resist the adhesion of fibroblasts. Moreover, in vitro and in vivo degradation experiments exhibited that mXG hydrogel was degradable and biocompatible. Finally, the rat model of sidewall defect-cecum abrasion was employed to evaluate the anti-adhesion efficacy of the mXG hydrogel. The results demonstrated that mXG hydrogel could effectively prevent postoperative peritoneal adhesion without side effects. The combination of suitable gel temperature, appropriate biodegradation period, and excellent postoperative anti-adhesion efficacy make mXG hydrogel a promising candidate for the prevention of postsurgical peritoneal adhesion.

STATEMENT OF SIGNIFICANCE

Despite numerous drugs or barrier-based devices have been developed to prevent postoperative adhesion, few solutions have proven to be uniformly effective in subsequent clinical trials. In the present study, we developed a biodegradable and thermoreversible galactose modified xyloglucan (mXG) hydrogel by green enzymatic reaction without using any organic reagents. The developed physical mXG hydrogel not only showed excellent injectability, appropriate gelation time and temperature, but also exhibited excellent biocompatibility and biodegradability both in vitro and in vivo. In addition, mXG hydrogel was easy to handle and could effectively prevent postoperative adhesion without side effects in a rat model of sidewall defect-bowel abrasion. Our study provide a safe and effective postoperative anti-adhesion material which may have potential applications in clinical practice.

Efficacy of Hyaluronic Acid/Carboxymethyl Cellulose-Based Bioresorbable Membranes in Reducing Perihepatic Adhesion Formation: A Prospective Cohort Study

BACKGROUND

Perihepatic adhesions induced by hepatectomy make the subsequent repeat hepatectomy technically demanding. The aim of this study was to verify the effect of hyaluronic acid/carboxymethyl cellulose-based bioresorbable membrane (HA membrane) in preventing posthepatectomy adhesion formation by focusing on the ease of the adhesiolysis in subsequent hepatectomy for recurrent tumors.

METHODS

A total of 201 patients who underwent hepatectomy using HA membrane were prospectively followed-up for 3 years. Thirty of the 201 patients underwent a repeat hepatectomy for recurrence. The operative data of 85 cases of repeat hepatectomy, the primary hepatectomy of which had been performed without the use of HA membrane, served as the historical control data. The primary endpoint was the time interval between the skin incision and the start of hepatic parenchymal transection (the preparation time) including adhesiolysis. Secondary endpoints were blood loss during the operation, incidence of postoperative complications, and the biochemical data.

RESULTS

The median preparation time (183 vs. 228 min; p = 0.027) and total operation time (374 vs. 439 min; p = 0.041) were significantly shorter in the HA membrane group than in the control group.

CONCLUSION

Use of HA membranes during hepatectomy enabled significant shortening of the adhesiolysis time during the sequential hepatectomy performed for recurrent tumors.

Randomized Controlled Trial of Hyalobarrier® Versus No Hyalobarrier® on the Ovulatory Status of Women with Periovarian Adhesions: A Pilot Study

Introduction

Periadnexal adhesions are known to contribute to subfertility. The restoration of the tubo-ovarian anatomy is one the key principles in reproductive surgery, and this involves adhesiolysis. However, adhesion formation/reformation is very common after periovarian adhesiolysis. It is not known if the application of Hyalobarrier^®, an anti-adhesion gel, around the adnexal region postsurgery influences ovulatory status. The study is a pilot randomized controlled trial (RCT) randomizing women into the application of Hyalobarrier^® versus no Hyalobarrier^® at the time of laparoscopy, where postsurgical ovulatory status and pregnancy rates were evaluated.

Methods

This was a pilot RCT where women were recruited from the gynecological and subfertility clinic who were deemed to require an operative laparoscopy. If intraoperatively they were found to have periovarian adhesions, they were randomized into having adhesiolysis with and without usage of Hyalobarrier^®. Demographic details and intraoperative details including the severity, extent, and the ease of use of Hyalobarrier^® were recorded. Prior to the surgery and postoperatively, the participants had their serum hormonal status (day 2 FSH, LH and day 21 progesterone) evaluated. Postoperatively, they underwent a follicular tracking cycle at 3 months.

Results

Fifteen women were randomized into use of Hyalobarrier^® (study group) and 15 into the no Hyalobarrier^® group (control group) between December 2011 and January 2014. There was no difference in the patient characteristics in terms of age, BMI, the number of previous pregnancies, or the extent, site, and severity of adhesions between the two groups. There was no significant difference between the study versus control groups in terms of the hormonal profile (day 2 FSH and day 21 progesterone) before or after surgery. The 3-month postoperative day 10–12 follicular tracking findings and endometrial thickness were similar between the study and control groups. Four women were pregnant in the study group (24%) and one in the control group (7%) cumulatively over 2 years.

Conclusion

The use of Hyalobarrier^® post salpingo-ovariolysis did not influence follicular development as inferred from the results of the day 21 progesterone and folliculogram on day 10–12 3-month postsurgery.

Trial Registration

ISRCTN number, ISRCTN1833588.

Funding

Nordic Pharma.

Sepramesh and postoperative peritoneal adhesions in a rat model

PURPOSE

The present study aimed to investigate the safety and the anti-postoperative peritoneal adhesion (PPA) characteristics of Sepramesh^® (Davol), a composite mesh made of polypropylene covered with Seprafilm, when intraperitoneally placed in a rat model.

METHODS

Twenty male rats were randomized into a control group and a Sepramesh group. They underwent a primary surgical procedure aiming to induce a peritoneal injury in order to induce PPAs. In the Sepramesh group, the burnt peritoneum was covered with a 2-cm diameter disc of Sepramesh prosthesis. The mesh was fixed to the parietal peritoneum with four 3-0 absorbable stitches. PPAs were assessed during a second laparotomy 10 days later using quantitative and qualitative scoring systems.

RESULTS

There was no difference in terms of mean number of PPAs between both groups. All the rats from the control group developed PPAs. In the Sepramesh group, no adhesions were observed at the site of the injured peritoneum that had been covered with the Sepramesh prosthesis, but PPAs occurred at the extremities of the mesh, where there was close contact between polypropylene and viscera, or where the fixation sutures were placed. The severity and the type of adhesions were significantly higher in the control group.

CONCLUSIONS

This study demonstrated that for the Sepramesh prostheses, the Seprafilm layer might be effective in PPA prevention, but damage caused by the section and fixation of Sepramesh should be limited in order to limit PPAs.

Recombinant human lubricin for prevention of postoperative intra-abdominal adhesions in a rat model

BACKGROUND

Postoperative intra-abdominal adhesions are a major cause of morbidity and mortality and contribute to a heavy burden on health care resources. At present, numerous introduced adhesion prevention products have demonstrated some benefit but none are consistently effective. The aim of this study was to examine the effectiveness of recombinant human lubricin in preventing intra-abdominal adhesion formation.

MATERIALS AND METHODS

A total of 62 male Wistar Albino rats were randomly assigned to the study. Six rats were used to the initial pilot study and 56 rats were randomized into four groups: (1) control cecal abrasion; (2) treatment cecal abrasion with 0.5 mg/mL lubricin solution; (3) control cecal enterotomy and primary closure; and (4) treatment cecal enterotomy and primary closure with 0.5 mg/mL lubricin solution. Rats were sacrificed at 3 d and 21 d postoperatively for the pilot and main studies, respectively. Macroscopic and microscopic adhesion severity was graded by blinded investigators.

RESULTS

For the pilot study, all six rats successfully reached the end point indicating safety of the lubricin gel. In the main randomized study, adhesions in the treated cecal abrasion group were significantly reduced both macroscopically (P = 0.001) and microscopically (fibrosis P = 0.009, inflammation P < 0.0001), when compared with the control group. In the cecal enterotomy group, adhesions were reduced for the treatment group in macroscopic (P = 0.011) and microscopic grading (fibrosis P = 0.500, inflammation P = 0.206) compared with the control group.

CONCLUSIONS

Recombinant human lubricin significantly reduced both macroscopic and microscopic intra-abdominal adhesions in the cecal abrasion group. The cecal enterotomy group showed modest macroscopic adhesion reduction. Future study using higher concentration of lubricin solution are needed to investigate its toxicity and more profound antiadhesion properties in significant operations.

Evaluation of the Effectiveness of Peritoneal Adhesion Prevention Devices in a Rat Model

BACKGROUND

Abdominal operations are followed by adhesions, a prevalent cause of abdominal pain, and the most frequent cause for bowel obstruction and secondary female infertility. This rat study addresses adhesion prevention capability of Adept(®), Interceed(®), Seprafilm(®), and a novel device, 4DryField(®) PH which is provided as powder and generates its effect as gel.

METHODS

Sixty-eight male Lewis rats had cecal abrasion and creation of an equally sized abdominal wall defect, and were grouped randomly: A control group without treatment (n=10); two groups treated with 4DryField(®) PH using premixed gel (n=15) or in-situ gel technique (n=16); one group each was treated with Seprafilm(®) (n=8), Interceed(®) (n=9), or Adept(®) (n=10). Sacrifice was on day 7 to evaluate incidence, quality, and quantity of adhesions, as expressed via adhesion reduction rate (AR). Histologic specimens were evaluated. Statistical analyses used ANOVA and unpaired t-tests.

RESULTS

4DryField(®) PH significantly reduced incidence and severity of adhesions both as premixed gel (AR: 85.2%) and as in-situ made gel (AR: 100%), a comparison between these two application techniques showed no differences in efficacy. Seprafilm(®) did not reduce incidence but severity of adhesions significantly (AR: 53.5%). With Interceed(®) (AR: 3.7%) and Adept(®) (AR: 16.1%) no significant adhesion-reduction was achieved. Except for inflammatory response with Interceed(®), histopathology showed good tissue compatibility of all other devices.

CONCLUSION

4DryField(®) PH and Seprafilm(®) showed significant adhesion prevention capabilities. 4DryField(®) PH achieved the highest adhesion prevention effectiveness without restrictions concerning mode of application and compatibility and, thus, is a promising strategy to prevent abdominal adhesions.

Pelvic pedicled omental flaps and autologous free omental grafts in a rabbit model

BACKGROUND

There is a need to identify an inexpensive, effective method to prevent postoperative adhesion formation. The objective of this study was to create a novel model for studying omentum as a pelvic adhesion barrier. Randomized, prospective, controlled surgical intervention with serial follow-up in 16 female rabbits at a University-based Center for Comparative Medicine. Interventions included bilateral hysterotomy incision and repair. The left hysterotomy was randomized into coverage with an omental flap or graft; the right hysterotomy remained uncovered. Adhesions were scored via laparoscopy on postoperative days 2, 4, 8, and 12; postmortem evaluation and scoring took place on postoperative day 16. Statistical tests consisted of Kappa tests of agreement between adhesion scorers and Kruskal-Wallis nonparametric tests for the comparison of adhesion scores by intervention arm and by uterine horn.

RESULTS

All omental flaps and grafts survived. The only significant difference in mean adhesion scores was seen in non-hysterotomy-associated adhesions, where grafts had a lower score than flaps (p = 0.03).

CONCLUSIONS

Survival of all omental flaps and grafts demonstrates that this is a practical model for studying omentum as a pelvic adhesion barrier. Determining the efficacy of omentum as a pelvic adhesion barrier will require further investigation.

Anti-adhesion barrier gels following operative hysteroscopy for treating female infertility: a systematic review and meta-analysis. ACTA ACUST UNITED AC. 2014;11:113-127. [PMID: 24795547 PMCID: PMC4003345 DOI: 10.1007/s10397-014-0832-x]

The aim of this study was to assess the effects of any anti-adhesion barrier gel used after operative hysteroscopy for treating infertility associated with uterine cavity abnormalities. Gynecologists might use any barrier gel following operative hysteroscopy in infertile women for decreasing de novo adhesion formation; the use of any barrier gel is associated with less severe de novo adhesions and lower mean adhesion scores. Nevertheless, infertile women should be counseled that there is at the present no evidence for higher live birth or pregnancy rates. There is a lack of data for the outcome miscarriage. Preclinical studies suggest that the use of biodegradable surgical barriers may decrease postsurgical adhesion formation. Observational studies in the human report conflicting results. We searched the Cochrane Menstrual Disorders and Subfertility Specialized Register (10 April 2013), the Cochrane Central Register of Controlled Trials (The Cochrane Library 2013, Issue 1), MEDLINE (1950 to 4 April 2013), EMBASE (1974 to 4 April 2013), and other electronic databases of trials including trial registers, sources of unpublished literature, and reference lists. We handsearched the Journal of Minimally Invasive Gynecology (from 1 January 1992 to 13 April 2013); we also contacted experts in the field. We included the randomized comparisons between any anti-adhesion barrier gel versus another barrier gel, placebo, or no adjunctive therapy following operative hysteroscopy. Primary outcomes were live birth rates and de novo adhesion formation at second-look hysteroscopy. Secondary outcomes were pregnancy and miscarriage rates, mean adhesion scores, and severity of adhesions at second-look hysteroscopy. Two authors independently assessed eligible studies for inclusion and risk of bias, and extracted data. We contacted primary study authors for additional information or other clarification. Five trials met the inclusion criteria. There is no evidence for an effect favoring the use of any barrier gel following operative hysteroscopy for the key outcomes of live birth or clinical pregnancy (risk ratio (RR) 3.0, 95 % confidence interval (CI) 0.35 to 26, P = 0.32, one study, 30 women, very low quality evidence); there were no data on the outcome miscarriage. The use of any gel following operative hysteroscopy decreases the incidence of de novo adhesions at second-look hysteroscopy at 1 to 3 months (RR 0.65, 95 % CI 0.45 to 0.93, P = 0.02, five studies, 372 women, very low quality evidence). The number needed to treat to benefit is 9 (95 % CI 5 to 33). The use of auto-cross-linked hyaluronic acid gel in women undergoing operative hysteroscopy for fibroids, endometrial polyps, or uterine septa is associated with a lower mean adhesion score at second-look hysteroscopy at 3 months (mean difference (MD) -1.44, 95 % CI -1.83 to -1.05, P < 0.00001, one study, 24 women; this benefit is even larger in women undergoing operative hysteroscopy for intrauterine adhesions(MD -3.30, 95 % CI -3.43 to -3.17, P < 0.00001, one study, 19 women). After using any gel following operative hysteroscopy, there are more American Fertility Society 1988 stage I (mild) adhesions (RR 2.81, 95 % CI 1.13 to 7.01, P = 0.03, four studies, 79 women). The number needed to treat to benefit is 2 (95 % CI 1 to 4). Similarly there are less' moderate or severe adhesions' at second-look hysteroscopy (RR 0.25, 95 % CI 0.10 to 0.67, P = 0.006, four studies, 79 women). The number needed to treat to benefit is 2 (95 % CI 1 to 4) (all very low quality evidence). There are some concerns for the non-methodological quality. Only two trials included infertile women; in the remaining three studies, it is not clear whether and how many participants suffered from infertility. Therefore, the applicability of the findings of the included studies to the target population under study should be questioned. Moreover, only one small trial studied the effects of anti-adhesion barrier gels for the key outcome of pregnancy; the length of follow-up was, however, not specified. More well-designed and adequately powered randomized studies are needed to assess whether the use of any anti-adhesion gel affects the key reproductive outcomes in a target population of infertile women.

Comparative study for preventive effects of intra-abdominal adhesion using cyclo-oxygenase-2 enzyme (COX-2) inhibitor, low molecular weight heparin (LMWH), and synthetic barrier

PURPOSE

Postoperative adhesion is the most frequent complication of abdominal surgery. Therefore, we investigated the individual effects of synthetic barrier [hyaluronic acid/carboxymethylcellulose (HA/CMC)] and pharmacologic agents [low molecular weight heparin (LMWH) cyclo-oxygenase-2 inhibitor (COX-2 inhibitor)] using animal model of intra-abdominal adhesion.

MATERIALS AND METHODS

The cecum was rubbed with sterile alcohol wet gauze until subserosal haemorrhage and punctate bleeding developed under the general anesthesia. Five animal groups were prepared using the film HA/CMC, gel HA/CMC, LMWH and COX-2 inhibitor.

RESULTS

The grade of adhesion by modified Leach method for group I (control), II (film type HA/CMC), III (gel type HA/CMC), IV (LMWH) and V (COX-2 inhibitor) were 5.35±1.8, 6.15±1.3, 4.23±2.6, 5.05±0.7 and 5.50±0.9, respectively. Group III showed the least grade of adhesion and it is statistically significant in adhesion formation (p=0.028). The numbers of lymphocytes were significantly low in group III and group V compared to the control group (lymphocyte: p=0.004). The mast cell counts were generally low except for the control group (I: 1.05, II: 0.35, III: 0.38, IV: 0.20, V: 0.37), however, it was not statistically significant (p=0.066).

CONCLUSION

The gel barriers were shown to be partly efficient in inhibiting the formation of postoperative adhesions and might provide an option for abdominal surgery to reduce postoperative adhesions. The LMWH and COX-2 inhibitor had been known for their inhibitor effect of fibrin formation and anti-angiogenic/ anti-fibroblastic activity, respectively. However, their preventive effects of adhesion and fibrosis were found to be obscure.

Adhesion awareness: a nationwide survey of gynaecologists

OBJECTIVE

Adhesions and related complications lead to substantially increased morbidity and mortality which increase medical costs. We investigated the awareness of adhesions among Dutch gynaecologists and gynaecology residents.

STUDY DESIGN

A survey, assessing knowledge and opinion about adhesions, was sent to a randomly selected group of 381 gynaecologists and 256 residents. In addition, the informed consent process and application of anti-adhesive agents were questioned.

RESULTS

The response rate was 56.9%. Complications due to adhesions were highly underestimated, leading to low knowledge scores (mean score 35.1%). Of all respondents 73.8% agreed that adhesions exert a clinically relevant and negative effect, but only 51.2% expressed a positive opinion on adhesion prevention. This correlated with a stronger belief in the clinically relevant and negative effects of adhesions and the opinion that adhesion prevention belongs to standard care (ρ=0.212, p<0.001; ρ=0.495, p<0.001). Of all respondents 31.4% expressed a positive attitude towards anti-adhesive agents and 19.8% expressed a negative one. A negative attitude correlated with a negative view in terms of cost-benefits (ρ=0.245, p<0.001). Although 43.5% had used anti-adhesive agents in the past year, 20.9% had used them before but stopped using agents in the past year. Only 5.2% routinely included adhesions or related morbidity in the informed consent.

CONCLUSIONS

Awareness of adhesions is limited and informed consent is provided inadequately. Implementing adhesion prevention is related with awareness of adhesions. These findings underline the need to embed adhesions, related morbidity and prevention in educational programmes.

Preventing adhesions in obstetric and gynecologic surgical procedures

Adhesive disease represents a significant cause of morbidity for postoperative patients. Most surgical procedures performed by obstetrician-gynecologists are associated with pelvic adhesions that cause subsequent serious sequelae, including small bowel obstruction, infertility, chronic pelvic pain, and difficulty in postoperative treatment, including complexity during subsequent surgical procedures. The technology of adhesion prevention has significantly progressed. There are 3 methods approved by the US Food and Drug Administration for the prevention of postoperative adhesions, including Adept((R)), Interceed((R)), and Seprafilm((R)). The latter barrier is the most widely studied. This article reviews the current choices available for adhesion prevention barriers as well as surgical adjuncts that traditionally have been studied for that purpose.