The peritoneal response to expanded polytetrafluoroethylene and oxidized regenerated cellulose surgical adhesion barriers

Identification of macrophages at the site of peritoneal injury: evidence supporting a direct role for peritoneal macrophages in healing injured peritoneum

OBJECTIVE

To determine if peritoneal macrophages are present at the site of a surgical injury to the peritoneum during wound healing.

DESIGN

Controlled research study.

SETTING

Academic research laboratory. EXPERIMENTAL MODEL: A murine model of peritoneal wound healing.

INTERVENTION(S)

Intraperitoneal injection of polystyrene beads 1 hour after a surgical peritoneal injury to identify peritoneal macrophages.

MAIN OUTCOME MEASURE(S)

Presence of peritoneal macrophages at the site of the healing wound as determined by intracellular polystyrene beads on transmission electron microscopy 1, 3, 7, and 14 days after injury.

RESULT(S)

Peritoneal macrophages were easily distinguished from other cell types by the phagocytosis of polystyrene beads. One day after injury, peritoneal macrophages were adherent to the wound surface. By 3 days, mesothelial cells began covering the peritoneal macrophages at the wound surface and peritoneal macrophages were identified deep within the wound. Seven days after injury, the mesothelial layer was completely reconstituted, but peritoneal macrophages persisted within the healing would below the surface mesothelium.

CONCLUSION(S)

These data indicate that peritoneal macrophages are present at the peritoneal injury site throughout the healing interval and are consistent with these macrophages having a critical role in peritoneal wound healing.

A barrier composed of chemically cross-linked hyaluronic acid (Incert) reduces postoperative adhesion formation

OBJECTIVE

To test whether a barrier of chemically cross-linked pure hyaluronic acid reduces postoperative adhesion formation.

DESIGN

The material was evaluated in the murine uterine horn model using excision and electrocautery injuries and in animals who had amounts of material inserted into the abdomen to evaluate toxicity.

SETTING

Academic medical center.

SUBJECT(S)

Mice.

INTERVENTION(S)

Insertion of the barrier between uterine horns and into the peritoneal cavity.

MAIN OUTCOME MEASURE(S)

Adhesion formation at 14 days; the histology of the peritoneum, liver, and spleen at 42 days; and the number, differential count, morphology, and flow cytometry of peritoneal leukocytes 3 days postoperatively.

RESULT(S)

Fewer adhesions were present when excision injuries were separated by the barrier (12 of 28 sites [43%] versus 23 of 26 control sites [88%]), whereas the number of adhesions was unchanged after electrocautery injuries (14 of 26 sites [54%] versus 17 of 26 control sites [65%]). The uterine horn sites covered by the barrier were histologically indistinguishable from controls. No adverse impact on the peritoneum and peritoneal fluid leukocyte population was observed with barrier insertion.

CONCLUSION(S)

The use of a barrier composed of a chemically cross-linked hyaluronic acid derivative (Incert, Anika Therapeutics, Inc., Woburn, MA) reduced postoperative adhesion formation in this model without any adverse impact on the peritoneum and peritoneal leukocyte population. This barrier material shows promise in preventing postoperative adhesions and deserves clinical evaluation.

Removal of surgical barriers of expanded polytetrafluorethylene at second-look laparoscopy was not associated with adhesion formation

OBJECTIVE

To evaluate whether the surgical trauma required for the laparoscopic removal of a polytetrafluoroethylene (PTFE) surgical barrier would cause postoperative adhesions.

DESIGN

Two case reports.

SETTING

Tertiary academic medical center.

PATIENT(S)

Two women who had undergone myomectomy with placement of a PTFE surgical barrier and who were free of adhesions with the barrier in place.

INTERVENTION(S)

Removal of the PTFE barrier by laparoscopy 11 days after myomectomy.

MAIN OUTCOME MEASURE(S)

Adhesions at the site of removal of the PTFE barrier at the time of incidental laparoscopy several years later.

RESULT(S)

Adhesions were not present at the site of PTFE barrier removal.

CONCLUSION(S)

The surgical trauma required to remove PTFE barriers at early second-look laparoscopy was not associated with postoperative adhesions.