How do dense adhesions increase the risk of bleeding in gynecology surgery?

How Dense Adhesions Increase Bleeding Risk in Gynecologic Surgery

Dense adhesions significantly increase intraoperative bleeding risk by distorting normal tissue planes, obscuring vascular anatomy, and requiring extensive dissection through highly vascularized scar tissue that is prone to injury during adhesiolysis. 1

Primary Mechanisms of Increased Bleeding

Anatomic Distortion and Vascular Injury

• Dense adhesions obliterate normal tissue planes, making it difficult to identify and safely dissect around blood vessels, which leads to inadvertent vascular injury during adhesiolysis 1
• The tenacity of adhesions varies throughout the abdomen, with denser adhesions requiring more aggressive dissection that increases the risk of bleeding 1
• Severe adhesions cause difficulty in dissecting tissue planes, significant bleeding, and lengthy operative time, particularly when adhesions involve the bladder or rectum 2

Increased Surgical Complexity

• Dense adhesions between pelvic structures require complicated adhesiolysis to obtain sufficient access to the operative field, with injuries during adhesiolysis most frequently involving bowel and vascular structures 1
• The Peritoneal Adhesion Index (PAI), which measures adhesion tenacity on a 1-3 scale, has been validated as prognostic for the risk of injuries during adhesiolysis 1
• Operations lasting longer than expected due to adhesion complexity increase bleeding risk, with prolonged duration of anesthesia showing increased risk for vascular events 3

Clinical Significance in Specific Gynecologic Procedures

Impact on Staging and Cytoreductive Surgery

• FIGO stage I ovarian tumors with dense adhesions to other pelvic structures should be "upstaged" and treated as FIGO II tumors, as the relapse rate and surgical complexity are similar 1
• Dense adhesions are considered a poor prognostic factor for patients with stage I ovarian disease and indicate more aggressive disease biology 1

Myomectomy and Hysterectomy Considerations

• The uterus is inherently well-vascularized, and adhesions significantly increase intraoperative blood loss during surgical removal 3
• Severe adhesions between the uterus and bladder or rectum, especially from endometriosis and multiple cesarean sections, cause significant bleeding and risk of unrecognized thermal injury leading to late-onset fistulae 2

Risk Stratification

Validated Prognostic Scoring

• The Peritoneal Adhesion Index (PAI) is the only validated score that correlates with both postoperative convalescence and the risk of injuries during adhesiolysis, measuring tenacity at 10 predefined sites 1
• Dense adhesions increase the odds of severe bleeding, with advanced stage disease (often associated with adhesions) increasing bleeding odds by 2.7-fold 3

Strategies to Minimize Bleeding Risk

Preoperative Planning

• Preoperative correction of anemia and storage of autologous blood dramatically reduce the need for homologous transfusion in cases where dense adhesions are anticipated 3
• Careful preoperative imaging and surgical planning are essential when dense adhesions are suspected 2

Intraoperative Techniques

• Careful attention to surgical blood loss using techniques such as vasopressin injection, application of tourniquets on vascular pedicles, and meticulous hemostasis can reduce complications 4, 3
• A modified technique combining vaginal and laparoscopic approaches with assistance of retractors can achieve safer dissection of tissue planes as close to the edge of adhesions as possible, avoiding visceral injuries and minimizing bleeding 2
• Use bipolar electrocautery or ultrasonic devices instead of monopolar electrocautery to reduce thermal spread and inadvertent vascular injury when dissecting through adhesions 5

Surgical Approach Selection

• Laparoscopic surgery reduces adhesion formation compared to open surgery (reoperation rates 1.4% vs 3.8%), though existing dense adhesions may necessitate open conversion 5
• One patient in a laparoscopic partial nephrectomy series underwent elective open conversion prior to the procedure specifically due to dense intra-abdominal adhesions 1

Common Pitfalls to Avoid

• Underestimating the bleeding risk associated with dense adhesions and failing to prepare adequate blood products preoperatively 3
• Using monopolar electrocautery in densely adherent tissue, which increases adjacent tissue temperature by 47°C compared to only 0.6°C with ultrasonic devices, risking unrecognized vascular injury 5
• Failing to "upstage" ovarian tumors with dense adhesions, which leads to inadequate treatment planning and underestimation of surgical complexity 1
• Attempting complex adhesiolysis without adequate surgical experience, as surgery should be performed by appropriately trained surgeons with experience in managing adhesions 1