Does Seprafilm really reduce adhesive small bowel obstructions?

The Determination of the Biocompatibility of New Compositional Materials, including Carbamide-Containing Heterocycles of Anti-Adhesion Agents for Abdominal Surgery

Due to traumatic injuries, including those from surgical procedures, adhesions occur in over 50% of cases, necessitating exclusive surgical intervention for treatment. However, preventive measures can be implemented during abdominal organ surgeries. These measures involve creating a barrier around internal organs to forestall adhesion formation in the postoperative phase. Yet, the effectiveness of the artificial barrier relies on considerations of its biocompatibility and the avoidance of adverse effects on the body. This study explores the biocompatibility aspects, encompassing hemocompatibility, cytotoxicity, and antibacterial and antioxidant activities, as well as the adhesion of blood serum proteins and macrophages to the surface of new composite film materials. The materials, derived from the sodium salt of carboxymethylcellulose modified by glycoluril and allantoin, were investigated. The research reveals that film materials with a heterocyclic fragment exhibit biocompatibility comparable to commercially used samples in surgery. Notably, film samples developed with glycoluril outperform the effects of commercial samples in certain aspects.

The effect of 4% icodextrin solution on adhesiolysis surgery time at the Hartmann's reversal: a pilot, multicentre, randomized control trial vs lactated Ringer's solution

OBJECTIVE

A pilot randomized controlled clinical multicentre trail was established to compare intraperitoneal 4% icodextrin (ID) solution with lactated Ringer's solution (LRS) on adhesion formation after Hartmann's procedure. The adhesiolysis surgery time during Hartman's reversal was used as a marker of the severity of adhesions.

METHOD

Patients scheduled for Hartmann's resection were randomized at surgery to either of the two study solutions used as an irrigant during the operation and instilled (1000 ml) at the end of surgery. During the reversal procedure, the time for small bowel adhesiolysis was recorded.

RESULTS

On completion of 17 eligible patients, an interim analysis was performed. There were no complications following the use of 4% ID solution. The mean (SD) total adhesiolysis times in patients treated with 4% ID solution and LRS were 30.8 (18.0) min and 47.6 (45.7) min, respectively. The mean reduction of 16.8 min, although greater than expected, was not statistically significant (P = 0.33) because of the large variance in adhesiolysis times. Further statistical analysis showed that to achieve significance for the observed differences and variance, a minimum of 240 patients in each group would be required.

CONCLUSION

Icodextrin treatment resulted in a decreasing trend in adhesiolysis time. The use of 4% ID solution in peritonitis patients seemed to be safe. Because of larger than expected variations in adhesiolysis times, this pilot study was underpowered to meet the study end-point and further statistical modelling estimated that significance cannot be reached within a reasonable time scale. Other models should be used to evaluate the efficacy of anti-adhesive agents.

Comparison of the two types of bioresorbable barriers to prevent intra-abdominal adhesions in rats

PURPOSE

The aim of this study was to evaluate the efficacy of two absorbable film barriers, polylactic acid and sodium hyaluronate-carboxymethyl cellulose, in preventing postoperative intra-abdominal adhesions, inflammation, and fibrosis in an animal model.

METHODS

Forty Wistar albino rats were grouped as polylactic acid, sodium hyaluronate-carboxymethyl cellulose, and control. All rats underwent laparotomy with subsequent cecal wall abrasion and abdominal wall injury. The two treatment groups received polylactic acid or sodium hyaluronate-carboxymethyl cellulose film barriers, while control group received nothing. On postoperative day 21, three observers graded the intra-abdominal adhesions and resected specimens. Fibrosis, inflammation, and adhesions were graded using quantitative scoring systems.

RESULTS

When compared to control group, polylactic acid group showed significantly less inflammation and adhesion (p < 0.005), while there was no significant difference for fibrosis. Sodium hyaluronate-carboxymethyl cellulose group has showed significantly less adhesions (p < 0.005), but there were no significant differences among fibrosis and inflammation when compared to control group. There were no significant differences between polylactic acid and sodium hyaluronate-carboxymethyl cellulose groups on adhesion formation, inflammation, or fibrosis.

CONCLUSIONS

Placement of polylactic acid or sodium hyaluronate-carboxymethyl cellulose film barriers between injured surfaces is associated with a significantly reduced rate of postoperative adhesions. No superiority was detected between two barriers.

Practical limitations of bioresorbable membranes in the prevention of intra-abdominal adhesions

INTRODUCTION

Intra-abdominal adhesions are a significant source of postoperative morbidity. Bioresorbable barriers composed of hyaluronic acid and carboxymethylcellulose (HA/CMC) reduce adhesion formation by physically separating injured or healing peritoneal surfaces. To assess whether the efficacy of a physical barrier can extend beyond the site of application, we evaluated the effectiveness of an HA/CMC barrier in preventing adhesions distal to the site of placement.

METHODS

Adhesions were induced in rats by creating peritoneal ischemic buttons on either side of a midline incision. An HA/CMC barrier (Seprafilm Genzyme) was intraoperatively placed either under the midline incision, unilaterally over half the ischemic buttons, or bilaterally over all ischemic buttons. Control buttons received no HA/CMC. On day 7 adhesions were scored. In similar experiments, peritoneal fluid was collected at 24 h to assess the effects of HA/CMC on tissue plasminogen activator activity.

RESULTS

Placement of HA/CMC under the midline incision did not reduce adhesion formation to distal ischemic buttons (72 +/- 7%) compared to controls (80 +/- 8%). Unilateral placement of HA/CMC significantly (p < 0.05) reduced adhesion formation to those ischemic buttons over which the barrier was applied (35 +/- 7%) compared to both contralateral (83 +/- 9%) and control (80 +/- 8%) ischemic buttons. The bilateral application of HA/CMC also significantly (p < 0.05) reduced adhesion formation to all ischemic buttons compared to controls (22 +/- 7% vs. 66 +/- 7%, respectively). HA/CMC did not affect peritoneal tPA activity.

CONCLUSIONS

Effective adhesion reduction by the physical barrier HA/CMC appears to be limited to the site of application in this rat model. Despite the presence of a bioresorbable membrane at predicted sites of adhesion formation in the peritoneal cavity, adhesions readily form to distal unprotected sites.