The effect of fibrin glue and peritoneal grafts in the prevention of intraperitoneal adhesions

[Peritoneal adhesion formation]

Postoperative peritoneal adhesions are common sequelae of abdominal surgery. Acute as well as chronic complications, including bowel obstruction, abdominal pain and infertility can arise from adhesion formation. So far, the only reliable treatment is surgical adhesiolysis, which in turn is accompanied by an increased risk of adhesion recurrence. Despite significant progress in modern perioperative medicine, only limited prophylactic approaches are available and atraumatic surgery is still the most important factor.Current research concepts focus on two major antiadhesion strategies: firstly, the intraoperative placement of mechanical barriers and secondly novel immunomodulation concepts. Clinical data about the use of antiadhesive barriers show a heterogeneous outcome. Promising data have arisen from the immunomodulatory approaches and now require a step-up development from experimental to clinical trial level.The present review gives a short overview about the current research on the pathophysiology and prevention of peritoneal adhesions. The promising data are encouraging and require realization of carefully designed prospective clinical trials.

Evaluation of a fibrin preparation containing tranexamic acid (Adhexil) in a rabbit uterine horn model of adhesions with and without bleeding and in a model with two surgical loci

OBJECTIVE

To compare the efficacy of a fibrin preparation supplemented with tranexamic acid (Adhexil) with that of established devices, and to determine whether its effect is limited to the site of application.

DESIGN

Rabbit uterine horns were abraded in nonbleeding and bleeding variants of an established adhesions model. In a separate study, a sidewall excision with approximation of the abraded cecum was added. Animals randomly received Adhexil at both, neither, or either loci.

SETTING

Laboratory study.

ANIMAL(S)

Seventy-two female New Zealand White rabbits (Oryctolagus cuniculus).

INTERVENTION(S)

Adhexil, Seprafilm or SprayGel and Interceed.

MAIN OUTCOME MEASURE(S)

The extent of adhesions was evaluated 13 to 16 days after surgery.

RESULT(S)

Adhexil reduced adhesions (15 +/- 7%; 15 +/- 4%) compared with controls (74 +/- 13%; 78 +/- 9%) in the bleeding and nonbleeding models, respectively. The reductions resulting from the use of Seprafilm (39 +/- 17%; 34 +/- 14%) or SprayGel (61 +/- 18%; 43 +/- 14%) (n = 4) were not statistically significant. In the bleeding model, Interceed (48 +/- 15%) reduced adhesions only modestly.

CONCLUSION(S)

In the combined uterine and sidewall model, Adhexil reduced selectively the extent and incidence of adhesions. The absolute and relative performance of Adhexil in an established adhesions model and in the presence of bleeding justifies its further investigation.

The effect of tranexamic acid in fibrin sealant on adhesion formation in the rat

The objective of the research was to determine the effect of the type, dose, and volume of anti-fibrinolytic agents (tranexamic acid, aprotinin) added to fibrin formulations, on adhesion development. Adhesions were induced in 228 male rats by creating apposing parietal and visceral peritoneal defects. Animals were randomized to receive no treatment or a fibrin formulation containing aprotinin or tranexamic acid. Seven days later the incidence of adhesions, and the force and energy required to detach them, were determined. Adhesions developed in 13/13 rats in the control and aprotinin groups. Treatment with fibrin (100 mg/ml tranexamic acid) resulted in adhesions in 4/14 rats (as strips, p < or = 0.0005), 4/10 rats (as spray, p < or = 0.0036), and 12/15 rats (by drip). The reduction of adhesions was dependent on the concentration of tranexamic acid with strip and spray application. Using commercial formulations, tranexamic-acid-containing fibrin (10/15, p = 0.042), but not aprotinin-containing fibrin (13/15), reduced the incidence of side-wall adhesions from 15/15 in controls. Fibrin containing either tranexamic or aprotinin reduced the incidence and severity of adhesions. This effect was greater when tranexamic acid was used and was dependent on the mode of administration, the volume, and to a degree, the concentration of tranexamic acid.

The impact of conventional and laparoscopic colon resection (CO2 or helium) on intraperitoneal adhesion formation in a rat peritonitis model

BACKGROUND

Although postoperative intra-abdominal adhesion formation has been shown to be less with laparoscopic procedures than with open surgery, the extent of intraperitoneal adhesion formation after open and laparoscopic colon resection in patients with intra-abdominal infection remains unclear.

METHODS

A standardized fecal inoculum was intraperitoneally applied in 72 rats to induce peritonitis. The rats were randomized into four groups. The three experimental groups underwent laparoscopic resection of the cecum with carbon dioxide (n = 20) or helium (n = 20) insufflation at a pressure of 8 mmHg, or conventional open cecum resection (n = 20). In the control group, no further manipulations were performed after induction of the peritonitis (n = 12). Blood samples were taken during the perioperative course to determine the plasma levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10). The number of intraperitoneal adhesions and the bacterial species of peritoneal swabs were determined in each animal.

RESULTS

The adhesions were increased in all operation groups as compared with the control group. The number of adhesions was significantly greater after conventional resection than after laparoscopic approaches (p < 0.01). The overall adhesion score was significantly lower in the helium group (p < 0.05) than in the two other operation groups. There was no difference between the laparotomy and carbon dioxide groups. Whereas postoperative TNF-alpha plasma levels were decreased, IL-10 levels were significantly greater in the helium group than in the other three groups.

CONCLUSIONS

Intraperitoneal infection is reducing the benefit of laparoscopic surgery regarding postoperative adhesions. Although laparoscopic resection showed an advantage in the number of adhesions with both gases, the total adhesion score was lowest in the helium group.

Effects of five different barrier materials on postsurgical adhesion formation in the rat

Postsurgical adhesion formation is a significant clinical problem within every surgical specialism. Due to the problems that adhesions cause, a wide variety of adjunctive treatments to prevent the formation and reformation of adhesions have been proposed. One of the modalities that has been studied extensively and that has been showing the most promising results is the so-called barrier method. The purpose of the present study was to compare the efficacy of five of these barrier materials in the prevention of postsurgical adhesion formation in a standardized rat adhesion model. It was concluded that no beneficial effect of Ringer's lactate on adhesion formation was seen. Significant reductions (P < 0.0001) in adhesion percentages compared to control animals were seen with Polyactive((TM)), PRECLUDE Peritoneal Membrane((TM)), Seprafilm((TM)) and Tissucol((TM)), but only PRECLUDE Peritoneal Membrane and Seprafilm significantly reduced adhesions (P < 0.01) when the barrier-treated peritoneal defects were compared with contralateral control-side peritoneal defects. The results of our study suggest that Seprafilm and PRECLUDE Peritoneal Membrane are superior to Tissucol and Polyactive in preventing adhesion formation. When Polyactive was still attached to the site of application during the second laparotomy, similar results to Seprafilm and PRECLUDE Peritoneal Membrane were seen. Future studies on the efficacy of a material to decrease adhesion formation should always include a comparison of several control materials in the same model. Our study indicates that Seprafilm or PRECLUDE Peritoneal Membrane might be used as standards of control.

Fibrinolysis in the peritoneal fluid during adhesions, endometriosis and ongoing pelvic inflammatory disease

The concentrations of the specific activators (u-PA and t-PA) and the specific inhibitors (PAI-1 and PAI-2) of the fibrinolytic system were analyzed in the peritoneal fluid in women suffering from intra-abdominal adhesions, endometriosis or pelvic inflammatory diseases (PID). Peritoneal fluids were collected from ten women in whom a laparotomy was performed and an additional 108 in whom a laparoscopy was carried out. In comparison with the normal control patients all activators and inhibitors were significantly increased in cases of PID and when a second-look laparoscopy was performed one week after laparotomy with adhesiolysis. At laparoscopies, when adhesions were verified, u-PA in the peritoneal fluid was significantly increased and in cases of endometriosis PAI-2 was significantly reduced. The start of a laparotomy in order to remove adhesions, initiates a process, resulting in a significant increase of PAI-2 antigen in the pelvic fluid. The results imply that the fibrinolytic system is comprehensively activated in the peritoneal cavity during ongoing inflammatory reaction, and after adhesiolysis. The increase in plasminogen activators in the peritoneal fluid in established cases of pelvic adhesions or endometriosis may indicate that the fibrinolytic system is continuously active to inhibit the further formation of adhesions.

Adhesion formation of the parietal and visceral peritoneum: an explanation for the controversy on the use of autologous and alloplastic barriers?

OBJECTIVE

To compare formation of adhesions after injury to both parietal and visceral peritoneum and to determine the benefit of autologous transplants and alloplastic barriers in adhesion prevention.

DESIGN

Experimental prospective animal study and prospective randomized clinical study.

SETTING

An academic research environment.

PATIENT(S)

Forty women undergoing laparoscopy for endometriosis treatment.

INTERVENTION(S)

In 60 rats, either the visceral or parietal peritoneum was injured and covered with autologous peritoneal transplants in half of the animals. The formation of adhesions was assessed 21 days postoperatively. In women, adhesions were evaluated 3 months after surgery with or without placement of alloplastic barriers on visceral lesions.

MAIN OUTCOME MEASURE(S)

Adhesions evaluated according to a scoring system.

RESULT(S)

Adhesions after injury of the visceral peritoneum in rats were significantly more severe than those from the parietal peritoneum. Autologous peritoneal transplants led to fewer adhesions especially after serosal injuries. Female volunteers treated with alloplastic barrier material showed less severe adhesions than the control group.

CONCLUSION(S)

The present data indicate that the potential to form adhesions is significantly higher in visceral than in parietal peritoneal lesions. The development of adhesions after injury to the visceral peritoneum could be reduced by a synthetic barrier material.