Predicting formation of adhesions after gynaecological surgery: development of a risk score

Perspectives in adhesion prevention in gynaecological surgery

Adhesions are a frequent, clinically relevant, and often costly complication of surgery that can develop in any body location regardless of the type of surgical procedure. Adhesions result from surgical trauma inducing inflammatory and coagulation processes and to date cannot be entirely prevented. However, the extent of adhesion formation can be reduced by using good surgical technique and the use of anti-inflammatory drugs, haemostats, and barrier agents. Strategies are needed in the short-, medium- and longer-term to improve the prevention of adhesions. In the short-term, efforts are needed to increase the awareness amongst surgeons and patients about the potential risks and burden of surgically induced adhesions. To aid this in the medium- term, a risk score to identify patients at high risk of adhesion formation is being developed and validated. Furthermore, available potentially preventive measures need to be highlighted. Both clinical and health economic evaluations need to be undertaken to support the broad adoption of such measures. In the longer- term, a greater understanding of the pathogenic processes leading to the formation of adhesions is needed to help identify effective, future treatments to reliably prevent adhesions from forming and lyse existing ones.

Risk Factors for Adhesion-Related Readmission and Abdominal Reoperation after Gynecological Surgery: A Nationwide Cohort Study

More than half of women in developed countries undergo surgery during their lifetime, putting them at risk of adhesion-related complications. Adhesion-related complications include small bowel obstruction, chronic (pelvic) pain, subfertility, and complications associated with adhesiolysis during reoperation. The aim of this study is to predict the risk for adhesion-related readmission and reoperation after gynecological surgery. A Scottish nationwide retrospective cohort study was conducted including all women undergoing a gynecological procedure as their initial abdominal or pelvic operation between 1 June 2009 and 30 June 2011, with a five-year follow-up. Prediction models for two- and five-year risk of adhesion-related readmission and reoperation were constructed and visualized using nomograms. To evaluate the reliability of the created prediction model, internal cross-validation was performed using bootstrap methods. During the study period, 18,452 women were operated on, and 2719 (14.7%) of them were readmitted for reasons possibly related to adhesions. A total of 2679 (14.5%) women underwent reoperation. Risk factors for adhesion-related readmission were younger age, malignancy as indication, intra-abdominal infection, previous radiotherapy, application of a mesh, and concomitant inflammatory bowel disease. Transvaginal surgery was associated with a lower risk of adhesion-related complications as compared to laparoscopic or open surgeries. The prediction model for both readmissions and reoperations had moderate predictive reliability (c-statistics 0.711 and 0.651). This study identified risk factors for adhesion-related morbidity. The constructed prediction models can guide the targeted use of adhesion prevention methods and preoperative patient information in decision-making.

The prevention of postoperative port-site adhesion following single-port access (SPA) laparoscopic surgeries

ABSTRACT

No studies have examined the issue of intraabdominal port-site adhesion following single-port access (SPA) laparoscopic surgeries. The purpose of the present study was to investigate the clinical effects of temperature-sensitive adhesion barrier solution in preventing periumbilical adhesion in SPA laparoscopy. This was a prospective, single-arm study in which patients were given GUARDIX-SGTM after SPA laparoscopic surgery for benign gynecologic diseases. One gram of GUARDIX-SGTM was applied on the abdominal viscera just below the umbilical port site and adjacent abdominal wall prior to fascia closure. The primary endpoint was the incidence of postoperative adhesion evaluated by visceral sliding technique through transabdominal sonography after three months. Between June 2019 and March 2020, a total of 37 healthy patients without any history of previous abdominal surgery received SPA laparoscopic surgery by a single surgeon. No postoperative complications such as wound dehiscence or surgical site infection occurred during the follow-up period of three months. No postoperative adhesion around the umbilicus was noted in all 37 patients. The mean visceral movement measured by transabdominal sonography during maximal respiration was 4.9 cm (4.9 ± 1.9 cm). Using an adhesion barrier around the port site prior to fascia closure prevents postoperative adhesion in benign SPA laparoscopic gynecologic surgery.

Genetic and Epidemiological Similarities, and Differences Between Postoperative Intraperitoneal Adhesion Development and Other Benign Fibro-proliferative Disorders

Intraperitoneal adhesions complicate over half of abdominal-pelvic surgeries with immediate, short, and long-term sequelae of major healthcare concern. The pathogenesis of adhesion development is similar to the pathogenesis of wound healing in all tissues, which if unchecked result in production of fibrotic conditions. Given the similarities, we explore the published literature to highlight the similarities in the pathogenesis of intra-abdominal adhesion development (IPAD) and other fibrotic diseases such as keloids, endometriosis, uterine fibroids, bronchopulmonary dysplasia, and pulmonary, intraperitoneal, and retroperitoneal fibrosis. Following a literature search using PubMed database for all relevant English language articles up to November 2020, we reviewed relevant articles addressing the genetic and epidemiological similarities and differences in the pathogenesis and pathobiology of fibrotic diseases. We found genetic and epidemiological similarities and differences between the pathobiology of postoperative IPAD and other diseases that involve altered fibroblast-derived cells. We also found several genes and single nucleotide polymorphisms that are up- or downregulated and whose products directly or indirectly increase the propensity for postoperative adhesion development and other fibrotic diseases. An understanding of the similarities in pathophysiology of adhesion development and other fibrotic diseases contributes to a greater understanding of IPAD and these disease processes. At a very fundamental level, blocking changes in the expression or function of genes necessary for the transformation of normal to altered fibroblasts may curtail adhesion formation and other fibrotic disease since this is a prerequisite for their development. Similarly, applying measures to induce apoptosis of altered fibroblast may do the same; however, apoptosis should be at a desired level to simultaneously ameliorate development of fibrotic diseases while allowing for normal healing. Scientists may use such information to develop pharmacologic interventions for those most at risk for developing these fibrotic conditions.

Post-Surgical Peritoneal Scarring and Key Molecular Mechanisms

Post-surgical adhesions are internal scar tissue and a major health and economic burden. Adhesions affect and involve the peritoneal lining of the abdominal cavity, which consists of a continuous mesothelial covering of the cavity wall and majority of internal organs. Our understanding of the full pathophysiology of adhesion formation is limited by the fact that the mechanisms regulating normal serosal repair and regeneration of the mesothelial layer are still being elucidated. Emerging evidence suggests that mesothelial cells do not simply form a passive barrier but perform a wide range of important regulatory functions including maintaining a healthy peritoneal homeostasis as well as orchestrating events leading to normal repair or pathological outcomes following injury. Here, we summarise recent advances in our understanding of serosal repair and adhesion formation with an emphasis on molecular mechanisms and novel gene expression signatures associated with these processes. We discuss changes in mesothelial biomolecular marker expression during peritoneal development, which may help, in part, to explain findings in adults from lineage tracing studies using experimental adhesion models. Lastly, we highlight examples of where local tissue specialisation may determine a particular response of peritoneal cells to injury.

The potential association between metabolic syndrome and risk of post-surgical adhesion

Metabolic syndrome (MetS) is defined by the clustering of several associated with a group of disorders that include: obesity, dyslipidemia, hypertension, and insulin resistance. The incidence of MetS is increasing globally around the world. Indeed the rates of different types of surgery in older or younger patients with Mets are increasing and they are exposed to a wide range of operations including abdominal, pelvic, urologic, or any invasive procedures. Post-surgical adhesion is a common problem and is a challenge for the surgeon. Despite many studies on its pathogenesis, there remain many un-answered questions about it, for example why certain tissues and patients are more at higher risk of post-surgical adhesions. Many studies have suggested that MetS is associated with up-regulating molecular mechanisms leading to chronic inflammation and hypercoagulability. In this review, we discuss some of the molecular mechanisms by MetS may enhance post-surgical adhesion, and particularly regarding those involved in coagulation and inflammation.

Clinical adhesion score (CLAS): development of a novel clinical score for adhesion-related complications in abdominal and pelvic surgery

Background

Adhesions are a major cause of long-term postsurgical complications in abdominal and pelvic surgery. Existing adhesion scores primarily measure morphological characteristics of adhesions that do not necessarily correlate with morbidity. The aim of this study was to develop a clinical adhesion score (CLAS) measuring overall clinical morbidity of adhesion-related complications in abdominal and pelvic surgery.

Methods

An international Delphi study was performed to identify relevant score items for adhesion-related complications, including small bowel obstruction, female infertility, chronic abdominal or pelvic pain, and difficulties at reoperation. The CLAS includes clinical outcomes, related to morbidity of adhesions, and weight factors, to correct the outcome scores for the likelihood that symptoms are truly caused by adhesions. In a pilot study, two independent researchers retrospectively scored the CLAS in 51 patients to evaluate inter-observer reliability, by calculating the Intraclass correlation coefficient. During a feasibility assessment, we evaluated whether the CLAS completely covered different clinical scenarios of adhesion-related morbidity.

Results

Three Delphi rounds were performed. 43 experts agreed to participate, 38(88%) completed the first round, and 32 (74%) the third round. Consensus was reached on 83.4% of items. Inter-observer reliability for the CLAS was 0.95 (95% CI 0.91–0.97). During feasibility assessment, six items were included. As a result, the CLAS includes 22 outcomes and 23 weight factors.

Conclusion

The CLAS represents a promising scoring system to measure and monitor the clinical morbidity of adhesion-related complications. Further studies are needed to confirm its utility in clinical practice.

Electronic supplementary material

The online version of this article (10.1007/s00464-020-07621-5) contains supplementary material, which is available to authorized users.

Pelvic adhesions and fertility: Where are we in 2018?

Peritoneal adhesions remain a major public health problem despite the development of laparoscopy. The rules of microsurgery must be known and followed during any pelvic surgery, even in patients who no longer have a desire for pregnancy. Anti-adhesion products are numerous. All have interest, confirmed by anatomical studies showing a smaller extent or a lesser severity of adhesions associated with their use. No studies, however, show clinical benefit in terms of improved pain or postoperative fertility. Pneumoperitoneum parameters, humidification, and lower abdominal pressure should be optimized to limit peritoneal trauma. Peri-operative corticosteroids, whose benefit has been has been demonstrated in at least one randomized trial, should be systematically used.

A first-in-human, randomized, controlled, subject- and reviewer-blinded multicenter study of Actamax™ Adhesion Barrier

Purpose

Post-surgical adhesions remain a significant concern following abdominopelvic surgery. This study was to assess safety, manageability and explore preliminary efficacy of applying a degradable hydrogel adhesion barrier to areas of surgical trauma following gynecologic laparoscopic abdominopelvic surgery.

Methods

This first-in-human, prospective, randomized, multicenter, subject- and reviewer-blinded clinical study was conducted in 78 premenopausal women (18–46 years) wishing to maintain fertility and undergoing gynecologic laparoscopic abdominopelvic surgery with planned clinically indicated second-look laparoscopy (SLL) at 4–12 weeks. The first two patients of each surgeon received hydrogel, up to 30 mL sprayed over all sites of surgical trauma, and were assessed for safety and application only (n = 12). Subsequent subjects (n = 66) were randomized 1:1 to receive either hydrogel (Treatment, n = 35) or not (Control, n = 31); 63 completed the SLL.

Results

No adverse event was assessed as serious, or possibly device related. None was severe or fatal. Adverse events were reported for 17 treated subjects (17/47, 36.2%) and 13 Controls (13/31, 41.9%). For 95.7% of treated subjects, surgeons found the device “easy” or “very easy” to use; in 54.5%, some residual material was evident at SLL. For 63 randomized subjects who completed the SLL, adjusted between-group difference in the change from baseline adhesion score demonstrated a 41.4% reduction for Treatment compared with Controls (p = 0.017), with a 49.5% reduction (p = 0.008) among myomectomy subjects (n = 34).

Conclusion

Spray application of a degradable hydrogel adhesion barrier during gynecologic laparoscopic abdominopelvic surgery was performed easily and safely, without evidence of clinically significant adverse outcomes. Data suggest the hydrogel was effective in reducing postoperative adhesion development, particularly following myomectomy.

Electronic supplementary material

The online version of this article (doi:10.1007/s00404-016-4211-x) contains supplementary material, which is available to authorized users.

Adhesions and endometriosis: challenges in subfertility management : (An expert opinion of the ANGEL-The ANti-Adhesions in Gynaecology Expert PaneL-group)

There is molecular evidence that endometriosis has a negative impact on the ovaries, although the exact pathophysiology concerning endometriosis-associated subfertility is not known. The negative impact on the tubo-ovarian unit can be directly by distorting the anatomy, indirectly by invoking inflammation or by oxidative damage with poorer-quality oocytes. Endometriosis even seems to have a negative effect on pregnancy outcome after in vitro fertilization.

Long term follow-up concerning safety and efficacy of novel adhesion prophylactic agent for laparoscopic myomectomy in the prospective randomized ADBEE study

We conducted a prospective randomized single blind - subject study in the University Clinic of Gynecology of Pius-Hospital Oldenburg. The primary objective of the ADBEE study was to assess the safety and manageability of ADBLOCK when used as an adjunct to laparoscopic surgery for the primary of myomas in women wishing to improve pregnancy outcomes. The study population included 32 women aged between 18-45 years, in good general health condition, who have not completed their family planning and who are undergoing primary ('virgin') laparoscopic myomectomy with an aim to improve pregnancy outcomes. The patients were randomized in 2 groups, ADBLOCK arm with 21 patients and surgery only arm with 11 patients. The study was single blind - subject and the investigators were blinded to treatment group assignment until completion of uterine suturing and prior to removal of the endoscope. A vigorous follow-up of subjects was organized, focusing on its two critical characteristics: completeness and duration. Completeness represented the percentage of subjects who returned to every planed follow - up appointments. The patients were evaluated in a specific period of time, which defined the duration of follow-up. Safety of the ADBLOCK was estimated after analyzing and documentation of any adverse events occurred, clinical and physical examination of patients as well as evaluation of laboratory measures. There were 25 adverse events reported in ADBLOCK treatment group and 12 events in NO-ADBLOCK group over the 24-months treatment. All adverse events in both treatment arms were not anticipated, with all events in the ADBLOCK group being resolved. At 28 days, there was no significant difference in proportion of events between the two treatments (p = 0.440). Overall, the number of events reported was low and the severity of events was generally mild with an unlikely or no relationship to treatment. There were no unanticipated device related adverse events seen in both treatment groups over the immediate post-operative period or during the 24 months follow up period. By 12 weeks all patients reported their wound as healing well or healed and at 6 months all wounds were reported as healed. There were no differences between both treatment groups regarding the use of painkillers over 24 months follow up period. This clinical first - in - human study, sustained by a rigorous follow-up of the subjects has demonstrated that ADBLOCK is a safe product, presenting no additional safety risk or burden to the patients over surgery alone. The device was relatively easy to use, with a low device failure rate that had no impact on the surgical procedures.