A carboxymethylcellulose-heparin combination for the prevention of surgical adhesions

Adhesions are a major clinical problem after abdominal surgery. Despite decades of research, therapies to prevent adhesion formation are suboptimal.

We have investigated combinations of carboxymethylcellulose (CMC) and heparin at preventing surgical adhesions in two rat models of adhesion formation. The first was the well-established cecal abrasion model, and the second was a model developed in our laboratory, the avascular mesenteric knot model. This model consistently produced adhesions at the knot in 90% of experiments and causes little or no tissue injury.

Topical administration of CMC 4% gave optimal results in the avascular knot model, but was less effective in the cecal abrasion model. This concentration of CMC was combined with a range of heparin doses between 0.5 and 160 IU/mL in the cecal abrasion model. These heparin doses, apart from the lowest (0.5 IU/mL), were effective in preventing adhesion formation in combination with CMC, as was the commercially available topical product Lipactin. The optimal dose was 30 IU/mL, that abolished adhesions, but there was little difference at doses between 2 and 160 IU. Heparin was effective in doses as low as 2 IU/mL when in combination with CMC. Heparin 160 IU/mL, but not heparin 30 IU/mL or Lipactin, significantly increased the degree of bleeding post cecal abrasion surgery.

Topical application of tiny doses of heparin, in combination with CMC 4% gel, significantly reduces adhesion formation in experimental models. We suggest that this cheap and, as far as we know, safe intervention should be evaluated in human clinical trials.