Adhesiolysis

Anatomy and Physiology

Postoperative abdominal adhesions are abnormal fibrous connections that develop between an organ and adjacent organs or tissues after surgery. They represent various tissue hyperplasia patterns, reflecting how different tissues respond to oxidative stress and injury. Because of this heterogeneity, adhesions can be classified according to the predominant tissue components present.[2] These include:

• Membranous adhesions
  • Consists of fibrin or hematoma clots and inflammatory cells such as neutrophils
• Vascular adhesions
  • Contains loose connective tissue with myofibroblasts, fibroblasts, collagen, and capillary vessels
• Adhesive adhesions
  • Characterized by dense connective tissue with myofibroblasts, resting fibroblasts, collagen type I, nerve fibers, arteries, and veins
• Scarred adhesions
  • Primarily contains collagen type I with a few myofibroblasts and resting fibroblasts

Adhesions may also be described as fibrinous or fibrous. Fibrinous adhesions typically develop in the early postoperative period; they are avascular, filmy, and often resolve spontaneously. By contrast, fibrous adhesions are dense and vascular and tend to entrap bowel, omentum, or other peritoneal structures, making them far more likely to cause complications such as chronic pain, infertility, and bowel obstruction.[8]

The pathogenesis of adhesions involves 3 principal mechanisms, though additional pathways continue to be investigated: (a) inhibition of fibrinolysis and extracellular matrix degradation; (b) activation of an inflammatory response with cytokine and transforming growth factor (TGF) production; and (c) tissue hypoxia leading to increased vascular endothelial growth factor (VEGF) expression.[1] Overall, an amplified cellular response to tissue damage, impaired fibrinolysis, and overexpression of VEGF and TGF-β are most strongly implicated in adhesion formation.[8]

Prevention strategies are grounded in meticulous surgical technique: minimizing cellular and vascular trauma with minimally invasive approaches, thoroughly clearing residual foreign material such as debris or blood clots, and achieving effective hemostasis.[2] Additional preventive measures include the application of physical barriers such as polymer membranes or gels containing hyaluronic acid, oxidized regenerated cellulose, polylactic acid, or polyethylene glycol; as well as emerging nanotechnology-based or biologic agents such as nanoparticle therapeutics, immunotherapy, and gene therapy. Despite these efforts, no surgical procedure or pharmacologic agent has been shown to prevent postsurgical adhesion formation reliably.[4]

When complications such as recurrent adhesive small bowel obstruction occur, elective adhesiolysis has been demonstrated to reduce the risk of further episodes compared with nonoperative management or the natural disease course.[3] Among currently available adjuncts, Seprafilm, a biodegradable membrane composed of hyaluronic acid and carboxymethylcellulose, is 1 of the best-studied options for adhesion prevention.[9] Icodextrin is another agent applied during adhesiolysis, with evidence suggesting it can lower recurrence rates.[10]

Indications

Clinicians must obtain a thorough history and perform a detailed physical examination to determine whether a patient requires adhesiolysis or may benefit from nonoperative care. Approximately 80% of patients with adhesive small bowel obstruction improve with conservative therapy; however, because the adhesions remain, complications such as recurrent bowel obstruction can still develop and ultimately necessitate surgical treatment by adhesiolysis. Although adhesiolysis is a recognized risk factor for further adhesion formation, results from newer studies refute the longstanding belief that it inevitably leads to recurrent bowel obstruction.[10]

The most common indication for adhesiolysis is bowel obstruction, where surgery is warranted in the presence of clinical or imaging features of ischemia, strangulation, perforation, peritonitis, or when nonoperative management fails.[11] Other accepted indications include chronic adhesion-related abdominopelvic pain—a diagnosis of exclusion made only after other potential causes of pain have been ruled out—particularly when symptoms are severe or progressive and may eventually culminate in bowel obstruction.[3] In selected cases, adhesiolysis may also be considered for infertility due to pelvic adhesive disease or when adhesions compromise the safe performance of planned abdominal or pelvic surgery.

Contraindications

Because adhesiolysis itself carries significant morbidity—including the risk of inadvertent enterotomy, bleeding, and formation of new adhesions—it should be undertaken only when the expected benefits outweigh these risks. Contraindications can be divided into absolute and relative categories, and careful patient selection is essential.

Absolute Contraindications

• Diffuse peritonitis or uncontrolled intra-abdominal sepsis not related to adhesive obstruction
  • In these cases, the priority is source control and damage-control surgery; formal adhesiolysis should be deferred until the patient is stabilized.
• Hemodynamic instability not attributable to adhesive obstruction
  • Unstable patients should undergo only life-saving procedures; extensive adhesiolysis increases operative time and risk.
• Known or suspected intra-abdominal malignancy requiring oncologic resection
  • The surgical plan is dictated by oncologic principles rather than by adhesiolysis alone.

Relative Contraindications

• Extensive “frozen abdomen” from dense, matted adhesions
  • The risk of inadvertent bowel injury is high and may outweigh the benefit unless there is frank obstruction or ischemia.
• Adhesions due to prior radiation therapy
  • Radiation causes blurring of normal anatomical planes and predisposes the patient to complications such as iatrogenic perforation.[9]
• Severe medical comorbidities or poor operative risk
  • Unless there is a life-threatening obstruction, conservative management is preferred. Patients who cannot tolerate pneumoperitoneum, for example, due to significant cardiopulmonary compromise or hemodynamic instability, should not undergo laparoscopic adhesiolysis.[11]
• Minimal or poorly defined symptoms
  • For chronic abdominal or pelvic pain where other etiologies are not definitively excluded, the likelihood of symptom relief after adhesiolysis is low and may not justify operative risks.
• Asymptomatic or incidentally discovered adhesions
  • Adhesiolysis is not indicated solely to prevent future obstruction, as the procedure can create new adhesions.

Practical Considerations

Timing is critical. In the early postoperative period (<6–8 weeks after prior surgery), adhesions are highly vascular and friable, increasing the risk of bleeding and enterotomy; elective adhesiolysis is generally avoided unless urgent. When adhesiolysis is relatively indicated, the choice between open and laparoscopic techniques should be individualized based on adhesion distribution and density, prior operative history, surgeon expertise, and overall patient risk profile.

Equipment

Laparoscopic or robotic techniques are generally preferred for adhesiolysis because a minimally invasive approach decreases postoperative pain, shortens hospital stay, and reduces the formation of future adhesions.[12] Entry into the abdominal cavity requires meticulous care, as dilated loops of small bowel and adherent structures are often present and highly susceptible to injury. When dense adhesions are anticipated, it is prudent to establish the initial laparoscopic port using an open (Hasson) technique to minimize the risk of visceral or vascular injury.

Adhesiolysis is typically performed with sharp dissection using scissors, with or without an energy source. In minimally invasive surgery, hook electrocautery is commonly used, but careful technique is essential to avoid lateral thermal spread. More recently, advanced bipolar electrosurgical devices and ultrasonic shearing instruments have demonstrated advantages such as reduced blood loss and shorter operative times. Regardless of the energy device chosen, surgeons must avoid creating new dissection planes and remain within established anatomic planes to prevent inadvertent injury. In open procedures, clips or suture ligatures may be required for hemostasis. Any serosal tears of the bowel or capsular injuries to solid organs should be repaired immediately to maintain organ integrity and achieve hemostasis.

Bioabsorbable adhesion barriers composed of hyaluronic acid and carboxymethylcellulose are occasionally applied to reduce postoperative adhesion formation further.[13] Multiple studies' results support the safety and efficacy of chemically modified sodium hyaluronate/carboxymethylcellulose absorbable barriers in lowering the incidence and severity of future adhesions. However, their routine use remains largely dependent on the clinician.[5] Notably, the widespread adoption of minimally invasive surgical techniques has significantly decreased the risk of adhesion formation.

Technique or Treatment

Patients may undergo open or laparoscopic adhesiolysis, occasionally in combination with mechanical or pharmacologic barrier techniques to limit future adhesion formation. The choice of approach depends on patient factors, surgeon expertise, and the clinical scenario.

Laparoscopic Adhesiolysis

Laparoscopic adhesiolysis generally yields superior short-term outcomes for adhesive small bowel obstruction, including lower morbidity, shorter hospital stay, and reduced postoperative pain.[14][15] The minimally invasive approach is associated with a lower risk of new adhesion formation and has become increasingly favored when technically feasible.[10] Despite these advantages, the laparoscopic approach carries distinct challenges. These include a risk of intraoperative bowel injury, difficulty manipulating or visualizing dilated loops of bowel, and higher procedural costs. In addition, incomplete adhesiolysis can lead to missed sites of occult obstruction.[10] Even in experienced hands, the conversion rate to open surgery remains significant, as shown in 32% to 38% of study results from 2001 to 2019. However, this rate has been decreasing with advancing techniques and technology.[14] The success of laparoscopy depends on careful patient selection, which has consistently been identified as the strongest determinant of successful outcomes.[7][15]

To minimize the risk of injury during abdominal entry and creation of pneumoperitoneum, a common technique is initial Veress needle insertion in the left upper quadrant, followed by placement of an optical separating trocar to enter the peritoneal cavity and avoid trocar-related injury safely. Once access is obtained, the surgeon performs a systematic examination of the bowel, beginning at the ileocecal junction and proceeding proximally, until the transition zone of obstruction is identified and released. For adhesiolysis itself, laparoscopic shears or advanced bipolar devices are frequently used to minimize thermal spread and reduce tissue trauma.[14]

Open Adhesiolysis

Open midline laparotomy remains the historical standard and is still the more common technique worldwide, particularly when diffuse or dense adhesions are present, when there is significant bowel dilatation, or when ischemia or perforation is suspected.[11] Open surgery provides direct tactile feedback and facilitates management of complex or matted adhesions, but is associated with greater postoperative pain, longer hospital stay, and a higher rate of future adhesion formation compared with laparoscopy.

Use of Adhesion-Prevention Barriers

In both open and laparoscopic procedures, mechanical or pharmacologic antiadhesive barriers can be applied to reduce the risk of recurrent adhesions and their complications. Such barriers, which work by separating injured peritoneal and serosal surfaces until mesothelialization occurs, have reduced the risk of recurrent bowel obstruction by 4- to 6-fold and significantly improved chronic pain at 6 months in 80% of patients.[3] Examples include Seprafilm, polyethylene glycol, hyalobarrier gel with activated protein C, and icodextrin.[10][11] The product choice varies depending on whether the procedure is open or laparoscopic.[11]

Pharmacologic Strategies

Because inflammatory and fibrinocoagulative pathways drive adhesion formation, pharmacologic interventions have been investigated to enhance peritoneal fibrinolysis. Agents such as human recombinant tissue plasminogen activator, streptokinase, and the angiotensin-receptor blocker telmisartan have shown promise in experimental studies for reducing adhesion formation by supplementing deficient plasminogen activation and fibrinolytic activity. However, these agents remain investigational, and their use is limited by potential complications such as bleeding; therefore, caution is warranted before their application.[11]

Summary

When performed in appropriately selected patients, laparoscopic adhesiolysis offers essential advantages over open surgery but requires meticulous technique, experienced surgeons, and readiness to convert to an open approach when necessary. The judicious use of mechanical or pharmacologic barriers can decrease the risk of future adhesion-related complications.

Complications

Adhesiolysis—whether performed laparoscopically or through an open approach—carries significant risks arising from both the underlying disease process and the procedure's technical challenges. Complications are typically classified as intraoperative or postoperative.

Intraoperative Complications

• Enterotomy or serosal injury
  • Inadvertent bowel injury occurs in up to 10% of patients undergoing adhesiolysis.[16]
  • These injuries may result in leakage of intestinal contents into the operative field, leading to intra-abdominal abscesses or surgical site infection, which can prolong hospitalization, increase the cost of care, and contribute to higher overall morbidity and mortality.
  • Early or, ideally, intraoperative identification of any injury is crucial to prevent downstream complications.
• Bleeding and vascular injury
  • Injury to mesenteric or abdominal wall vessels can occur, particularly when adhesions are dense or matted.
  • Prompt recognition and meticulous hemostasis are essential.
• Thermal injury
  • Electrosurgical or ultrasonic devices may cause lateral thermal spread, creating delayed bowel perforation if not used with caution.
• Conversion to open surgery
  • Laparoscopic procedures may require conversion (historically 32%–38%) because of poor visualization, uncontrolled bleeding, or unexpected findings.[14]

Early Postoperative Complications

• Bowel obstruction or ileus
  • May arise from residual or newly formed adhesions or postoperative edema
• Intraabdominal sepsis
  • Often a consequence of missed enterotomy or anastomotic leak if bowel resection was performed
• Hemorrhage or hematoma formation
• Wound complications
  • Infection, dehiscence, or incisional hernia, particularly after open surgery.
• General postoperative complications
  • Patients are susceptible to deep vein thrombosis (DVT), atelectasis, surgical site infection, and urinary tract infection.
  • Prophylactic measures—including incentive spirometry, pharmacologic or mechanical DVT prophylaxis, and timely removal of Foley catheters—are essential to reducing these risks.

Late Complications

• Recurrent adhesions and obstruction
  • Although results from newer studies indicate that adhesiolysis does not inevitably lead to recurrent bowel obstruction, adhesions can reform and remain a source of future obstruction or pain.[10]
• Chronic abdominal or pelvic pain
  • Symptoms may persist or recur despite technically successful surgery.
• Incisional hernia
  • Particularly after midline laparotomy.

Strategies to Mitigate Risk

Preventing complications begins with careful patient selection and meticulous surgical technique, including sharp dissection within anatomic planes and cautious use of energy devices. Early recognition of intraoperative injuries, especially enterotomy, is critical to minimize morbidity. Postoperatively, structured protocols for prophylaxis and surveillance, such as early ambulation, respiratory exercises, and infection prevention strategies, are essential to enhance patient safety and optimize outcomes.

Clinical Significance

Adhesions and their complications are a significant burden on the healthcare system. They account for increased morbidity, mortality, and healthcare costs, especially if the patient requires further surgical intervention.[1] Adhesions are responsible for morbidity and mortality of about 14% to 45% and 4%, respectively.[15] 

Estimates are that there are 300,000 hospitalizations annually in the United States, with an estimated cost of approximately 1.3 billion dollars yearly in the workup and management of adhesive small bowel disease.[17] For these reasons, healthcare professionals need to know and understand the concept and management of adhesions, which involve nonoperative management, adhesiolysis when indicated, and postoperative care.

Enhancing Healthcare Team Outcomes

Patients undergoing adhesiolysis require a highly coordinated, interprofessional approach to treatment, ensuring patient-centered care, optimizing outcomes, and maintaining safety. Clinicians, particularly surgeons, must integrate advanced technical skills in minimally invasive and open techniques with sound perioperative decision-making, selecting appropriate candidates, and determining the safest operative approach. Advanced clinicians, such as physician assistants and nurse practitioners, play a key role in preoperative evaluation, patient education, and postoperative monitoring, reinforcing instructions regarding early ambulation, diet advancement, and warning signs of complications. Nurses provide continuous bedside assessment, facilitate early detection of postoperative issues such as ileus or infection, and coordinate timely interventions. Pharmacists contribute by reviewing and optimizing perioperative medications, managing analgesia to reduce opioid exposure, and advising on prophylactic agents when antiadhesive barriers or adjunctive pharmacologic therapies are considered.

Clear, structured communication among all team members is critical to maintain patient safety and improve outcomes. Preoperative briefings and multidisciplinary rounds promote shared situational awareness, while standardized handoff tools and postoperative care pathways ensure that all professionals understand the surgical findings and anticipated recovery trajectory. Dietitians and physical therapists may be engaged to expedite nutritional recovery and early mobilization, which are central to enhanced recovery protocols. By fostering open communication, defining roles, and aligning goals of care, the interprofessional team can reduce complications, improve patient satisfaction, and enhance overall team performance in the complex care of patients requiring adhesiolysis.