Transmural migration of a retained surgical sponge into the intestinal lumen: an experimental study

A retained surgical sponge in the peritoneal cavity is an occasional misadventure in modern surgery. Such a sponge can migrate into the intestinal lumen, but its mechanism is still unknown. A piece of surgical sponge, measuring 4 x 4 centrimetres, was placed at different sites of the abdominal cavity of Wistar rats. Inspite of the absence of infection, entry of the sponge into the intestinal lumen was shown microscopically in 10 out of 36 rats. Parallel statistical analysis by Cutler-Ederer estimation was found to be 0.58 of condition probability at 6 months. Transmural migration of a retained surgical sponge was not only associated with different sites placing in the abdominal cavity (P = 0.680), but also whether a seromuscular incision was made or not (P = 0.306). A hypothesis, based on a study of microscopic and macroscopic pathology, is proposed as four stages: foreign body reaction, secondary infection, mass formation and remodeling.