Evaluation of CMC and HA solutions for adhesiolysis

Aqueous hyaluronic acid (HA) and carboxymethylcellulose (CMC) solutions were tested as tissue-protective coatings during lysis of surgical adhesions by blunt dissection or electrocautery in a rat cecal abrasion model. Phosphate-buffered saline (PBS) was used as a tissue coating solution in 200 female Sprague-Dawley rats prior to controlled cecal abrasion with a surgical gauze-tipped rotary abrader (four 1.5-cm-diameter areas; 70 g weight/60 revolutions/130 rpm). One-week after this initial cecal abrasion, rats were operated on again and adhesions were scored and lysed. The rats were randomly assigned to receive experimental tissue coating solutions either before (prelysis; n = 160) or after (postlysis; n = 40) adhesiolysis. Animals with prelysis coatings were further divided into blunt dissection or electrocautery adhesiolysis groups and were tested with 2 mL cecal coating of PBS, 0.4% HA, 0.5% CMC, or 1.0% CMC tissue coating solutions (n = 20/group). Rats treated postlysis received 2 mL cecal coating plus 2 mL intraperitoneal instillation of PBS, 1.8, 1.9, or 2.0% CMC. One week after adhesiolysis, rats were operated on again for final adhesion scoring. Prelysis tissue coating with 0.5 or 1.0% CMC solution appeared to inhibit adhesion reformation after blunt dissection, whereas 0.4% HA was not effective in this model. Solutions applied before electrocautery dissection or after blunt dissection were ineffective.