In vivo administration of tolmetin in hyaluronic acid modulates protease levels in postsurgical macrophage-conditioned media

Prevention of adhesion formation with intraperitoneal administration of tolmetin and hyaluronic acid

Adhesion formation after peritoneal surgery is a major source of postoperative complications and pain. Previous studies showed that intraperitoneal administration of the nonsteroidal anti-inflammatory drug tolmetin reduced adhesion formation after two types of peritoneal surgery. The effect of tolmetin combined with hyaluronic acid (HA), a high-molecular-weight glucosaminoglycan found in the extracellular matrix, on the formation of adhesions was examined. In this study, the effect of tolmetin in HA on adhesion formation was evaluated in a standardized rabbit model. The medicament was administered intraperitoneally at the end of surgery. One week after surgery, a second laparotomy was performed and the extent of adhesion formation was determined. A range of molecular weights (7.5 x 10(5)-2 x 10(6) Da) and viscosities (1000-25,000 centapoise) of HA in combination with tolmetin was effective in reducing adhesion formation. However, low viscosity HA solutions in combination with tolmetin, 0.5-2.0 mg/mL, were most efficacious in reducing adhesion formation. These data suggest that HA, in combination with tolmetin, acts as an effective carrier to reduce adhesion formation in the abdominal cavity after surgery.

Reduction of adhesion formation by intraperitoneal administration of anti-inflammatory peptide 2

Adhesion formation is a major source of postoperative morbidity and mortality. Therefore, the reduction of postoperative adhesion formation would be of clinical benefit. Various modalities have been shown to reduce adhesion formation, including fibrinolytic enzymes, nonsteroidal anti-inflammatory drugs, and barriers that reduce the apposition of sites of potential adhesion formation. This study examined the ability of a phospholipase A2 inhibitor, anti-inflammatory peptide 2 (antinflammin), to reduce the formation of intraperitoneal adhesions in two rabbit models of adhesion formation. In the sidewall model, antinflammin was administered via Alzet miniosmotic pump for the entire postoperative interval, and there was a dose-dependent reduction in the area of the sidewall injury that was involved in adhesions to the cecum and the bowel. In the double uterine horn model, antinflammin was administered via Alzet miniosmotic pump to the area of injury for either 1, 2, 3, or 7 days. Administration of antinflammin for as little as 24 h after surgery significantly reduced the extent of adhesion formation. Administration of the peptide for longer periods of time did not further increase the reduction in adhesion formation. These studies clearly demonstrate that postoperative administration of antinflammin to the site of injury reduced the formation of postoperative adhesions in two animal models.