Role of blood and fibrinogen in development of intraperitoneal adhesions in rats

Effects of Streptokinase and Normal Saline on the Incidence of Intra-abdominal Adhesion 1 Week and 1 Month after Laparotomy in Rats

Background:

Intra-abdominal adhesions after surgery are usually in the form of bands and can annoy the patient throughout life causing repeated surgical procedures. Therefore, any action to prevent adhesions after surgery can increase longevity and quality of life. For this aim, this study investigates the effect of streptokinase and normal saline on the 7^th day and 1 month after laparotomy.

Materials and Methods:

Experimental study was conducted on thirty healthy male Wistar rats weighing 200–250 g with age of 3 months divided into three groups of 10. Group I: No treatment, Group II: Received normal saline, and Group III: Received normal saline and streptokinase at the same time. One week and 1 month after laparotomy, the frequency of the presence or absence of adhesion bands was performed by a person who was unaware of the sample grouping. The collected information was analyzed with the SPSS software (version 16; SPSS Inc., Chicago, IL, USA).

Results:

Adhesion frequency was found to be 20% on the 7^th day (early) and 1 month after laparotomy (late) for Group 1, and it was 40% on early and late for Group II, while 0% on the early and late for Group III. Hence, in the group receiving streptokinase, no early or late adhesion was observed; therefore, it had a significant role in the prevention of intra-abdominal adhesions (P < 0.05). However, adhesions in the group receiving normal saline had no remarkable difference with the group receiving no drug (P > 0.05).

Conclusion:

According to the results of our study, we believe that streptokinase could be a good antiadhesive agent considering its effectiveness.

Efficacy of Bioactive Polypeptides on Bleeding and Intra-Abdominal Adhesions

BACKGROUND

Perioperative bleeding and postoperative adhesions are two problems encountered in abdominal surgery. Commercial products are available that decrease both bleeding and development of abdominal adhesions, but no products are effective in both situations. The combination of differently charged bioactive polypeptides, administered intraperitoneally, has previously been shown effective in decreasing postoperative adhesions. The present study is a pilot examination of the effects on perioperative bleeding and postoperative adhesions, applying the polypeptide concept.

METHODS

Standardized wounds in the liver and spleen were induced in 52 NMRI mice. The amounts of bleeding and postoperative adhesions were measured after 1 and 7 days, respectively. Separate animals were examined after 8 weeks for long-term healing of the parenchymal wounds.

RESULTS

Both parenchymal bleeding and the extent of adhesions significantly decreased (p = 0.001 and p = 0.029, respectively) as compared to controls. Histology after 8 weeks showed no clear signs of impaired or altered healing.

CONCLUSION

Intraperitoneal administration of differently charged polypeptides significantly decreased postoperative bleeding and postoperative adhesions. Bioactive polypeptides appear promising in the promotion of peritoneal healing and merits further studies.

Effect of streptokinase in the prevention of intra-abdominal adhesions in the rat

The objective of the present study was to assess the action of streptokinase, a streptococcal derivative with fibrinolytic capacity, in the prevention of intraperitoneal adhesions in rats. Eighty animals were divided into four groups of 20 each; group A (control) received isotonic saline by the intraperitoneal route, group B received streptokinase by the intraperitoneal route at the dose of 60.000 units/kg body weight diluted in 2 ml isotonic saline, group C received 60.000 streptokinase units diluted in 1 ml isotonic saline by the intravenous route, and group D received 30.000 streptokinase units in 2 ml isotonic saline by the intraperitoneal route and 30.000 streptokinase units diluted in 1 ml isotonic saline by the intravenous route. The animals were submitted at random to median laparotomy for the preparation of stitches inducing adhesions of the ischemic type according to the model of FERRAZ-NETO et al. (1991) modified, and sacrified with a lethal dose of sulfuric ether on the 3rd and 7th postoperative day. Streptokinase was found to be effective in the prevention of adhesions when used by the intraperitoneal route (p=0,0349) or when administered both intraperitoneal and intravenously (p=0,0073). Comparison of the 3rd and 7th posteperative day within the same group showed no significant difference, suggesting that the drug acts during the early period of the healing process. We conclude that streptokinase is effective in the prevention of adhesions formation when injected by the intraperitoneal route or by the combined intraperitoneal and intravenous routes at the dose employed in rats.

Injury and adhesion formation following ovarian wedge resection with different thermal surgical modalities

The purpose of this study is to determine the role of bleeding, acute thermal damage, and charring in adhesion formation. Postoperative adhesions were compared following ovarian wedge resection in 48 rabbits using different lasers, electrosurgery, and scalpel. Twelve ovaries were sectioned per modality, in randomized pairs. Acute thermal injury as assessed by histology, bleeding, and charring differed among the modalities used. Adhesions were assessed 4 weeks later, by an investigator completely blinded of the treatment protocol. The adhesion scores were 11.6 +/- 8.0 with pulsed Er:YAG laser; 11.9 +/- 7.5 with scalpel; 8.3 +/- 9.3 with electrocautery; 6.7 +/- 8.8 with a continuous (c.w.) Nd:YAG laser; 5.3 +/- 4.8 with c.w. CO2 laser; 3.1 +/- 2.7 with pulsed CO2 laser; 1.7 +/- 1.8 with pulsed Ho:YAG laser; and 0.8 +/- 1.5 in the control (no resection) group. Ho:YAG, Nd:YAG, and electrocautery were completely hemostatic. Bleeding was minimal with the CO2 lasers. Er:YAG and scalpel caused maximum bleeding, requiring hemostatic measures to prevent exsanguination. Charring occurred with electrocautery, CO2 laser, and Nd:YAG laser. Bleeding and charring correlated with adhesion formation, but the histological depth of thermal damage did not. The Ho:YAG laser is a hemostatic, fiber-optic compatible laser causing significantly fewer adhesions (P < 0.04) than scalpel, electrocautery, Nd:YAG, Er:YAG, and c.w. CO2 lasers. Clinical use of the Ho:YAG laser, and the role of carbonization in promoting adhesions, deserve further study.

Phosphatidylcholine prevents postoperative peritoneal adhesions: an experimental study in the rat

Phosphatidylcholine (PC) is the main constituent of the surface-active material coating peritoneal mesothelium. It may prevent postoperative adhesion formation through production of a lubricant film on mesothelial defects. We therefore examined the effect of its soluble form on surgically induced intraabdominal adhesions in rats. The adhesions were induced at laparotomy by any of four different operative models. PC was administered intraperitoneally (20 mg/rat) or intravenously (20 mg/rat or 50 mg/rat) at the end of the operation and on the second and third postoperative day. It was found that the degree of postoperative adhesion formation was significantly reduced by the intraperitoneal injection of PC in all 4 models. In contrast, no effect was achieved by the intravenous injection of PC, not even at a very high dose level. Our results suggest that soluble PC administered intraperitoneally might be a potent adjunct in postoperative adhesion prevention.

Reoperation for small intestinal obstruction

Today, intestinal adhesions represent the most frequent etiology for complete or partial intestinal obstruction. Although partial obstruction can be treated nonoperatively with a considerable likelihood of success, intestinal strangulation cannot uniformly be predicted or prevented. Complete intestinal obstruction is associated with a significant incidence of strangulation if not treated by a vigorous surgical approach. Consequently, complete intestinal obstruction secondary to adhesions is still a surgical disease. Attempts at control of the adhesion process include mechanical methods to prevent subsequent obstruction and chemical methods to prevent the adhesion process itself. The invasive mechanical methods appear dated. A variety of agents have been used either systemically or in the peritoneal cavity to prevent the establishment of intra-abdominal adhesions. Agents that do not contribute to subsequent morbidity or impede the native host defense mechanisms should be utilized. High-molecular-weight dextran and nonsteroidal anti-inflammatory agents show some promise of being both safe and effective. As is frequently the case, the bottom line in preventing and treating intra-abdominal adhesions is appropriate surgical technique. Intestinal adhesions can be related clearly to leaving damaged, devitalized, or ischemic tissue in the peritoneal cavity or to excessive roughness in handling of tissues. Steps such as avoidance of excessive suture material and unnecessary handling of the bowel will do much to prevent subsequent adhesion generation. Likewise, the surgical lysis of intraperitoneal adhesions is frequently fraught with complications such as intra-abdominal abscess or postoperative incisional failure. This is again related to surgical technique and most directly to the use of blunt dissection to divide adhesions. Knife dissection in the lysis of adhesions is recommended. This technique, combined with excellent intraoperative hemostasis, can be associated with a marked diminution in the incidence of postoperative fistulas and abscesses.

Adhesion formation associated with the use of absorbable staples in comparison to other types of peritoneal injury

Adhesion formation was assessed after inducing peritoneal injury with absorbable staples, absorbable suture, surgical excision or thermal injury. In addition, adhesion formation was assessed in the presence of Hyskon. Absorbable staples were associated with increased adhesion formation when compared to the other methods of injury. Hyskon appears to significantly reduce the formation of peritoneal adhesions at sites of peritoneal suturing, excision, and thermal injury, but did not reduce adhesion formation in the area of stapling.

Prevention and management of peritonitis in horses

Peritonitis and adhesions in the horse are best managed through prevention. Perioperative antimicrobial therapy, nonsteroidal anti-inflammatory therapy, experienced personnel, and good surgical techniques should minimize complications after surgery. Despite preventative measures, some horses still develop peritonitis after surgery. Immediate, intensive treatment is necessary to enhance their chances for survival.

Pathogenesis of adhesion formation/reformation: application to reproductive pelvic surgery

Pelvic adhesions are a major contributing factor to infertility in women with tubal peritoneal disease. Surgical treatment of such adhesions often does not resolve their presence. Such postoperative adhesion formation occurs despite the use of microsurgical techniques in a wide variety of surgical adjuvants. The process of adhesion formation represents a variation of the normal healing process of the peritoneum. However, rather than normal mesothelial healing, the fibrinous mass resulting from the peritoneal defect is infiltrated by fibroblasts with subsequent adhesion formation. A description of the pathophysiology of this process is described. The current understanding of the pathologic/pathophysiologic interaction of the surgical adjuvants with this process is described.

Adhesion prevention in the rabbit with sodium carboxymethylcellulose solutions

With the use of a rabbit surgical model, the ability of 1%, 2%, and 3% solutions of sodium carboxymethylcellulose to reduce postoperative uterine adhesions was determined. At all concentrations sodium carboxymethylcellulose was more effective than either 32% dextran 70 or heparinized lactated Ringer's solution. Neither the dextran nor Ringer's solution had a significant (p less than or equal to 0.05) effect. The beneficial effects of sodium carboxymethylcellulose were closely dose-dependent (correlation coefficient 0.97). Sodium carboxymethylcellulose is highly effective in reducing postoperative adhesions in laboratory animals, and additional studies are warranted to further define its efficacy and safety.

Late results of salpingostomy combined with salpingolysis and ovariolysis by electromicrosurgery in 54 women

In 1975 and 1976 all together 54 women were treated with electromicrosurgery for correction of infertility due to peritubal and periovarian adhesions combined with sactosalpinx. Besides the gentle and less traumatic microsurgical method, corticosteroids combined with oxyphenbutazone were given to prevent new adhesions. Hydropertubation was performed on the 2nd and 4th postoperative days. Twenty-one (39%) of the patients became pregnant, 4 of them twice. Out of the 21 patients, 17 gave birth to live children, while in 3 of the 21 patients spontaneous abortion occurred. One legal abortion was performed. No ectopic pregnancies were observed in this unselected material.

Pelvic adhesions following microsurgical and macrosurgical wedge resection of the ovaries

The incidence of postoperative adhesion formation following microsurgical and macrosurgical ovarian wedge resection was contrasted in 10 adult female rhesus monkeys. Bilateral wedge resection was performed on day 10 of the luteal phase using microsurgical technique on one ovary and macrosurgical technique contralaterally. Animals were examined 4 weeks postoperatively. Adhesion formation occurred in only one ovary in which microsurgery had been employed (10%). In contrast, adhesion formation followed macroscopic ovarian wedge resection in five ovaries (50%). All adhesions were periovarian, emanating from the suture line on the ovarian surface. Adhesions were most common on the nonovulatory ovary.

Comparison of avitene, topical thrombin, and gelfoam as sole hemostatic agent in tuboplasties

Forty-eight virgin guinea pigs were subjected to bilateral sectioning of the uterine horn and cuff type salpingostomy. Avitene, Topical Thrombin, or Gelfoam was used as the sole hemostatic agent in each of three study groups. Bipolar cauterization was used in a control series. These agents were compared with regard to ease of application, degree of adhesion formation, net surface area, and microscopic evaluation of degree of fibrosis and inflammatory reaction. The results revealed no statistically significant differences among the various methods of hemostasis. Data were evaluated by uni- and multivariate analyses. Several trends in the data were noted: the greatest amount of fibrosis was associated with Topical Thrombin and Avitene, and the greatest inflammatory response was associated with Avitene. These agents show no superiority to currently used cautery methods of obtaining hemostasis.