Intraperitoneal delivery of drugs or fluids is something that occurs much more frequently in veterinary medicine than clinical medicine. In veterinary medicine or scientific studies using animals, compounds are frequently given via this route that it is typically referred to as "i.p. injection" or "i.p. delivery".
When glucose is delivered via this route (by injection or catheter directly into the peritoneal space), how does the glucose actually get into the systemic circulation? That is, where does it actually go anatomically?
I can't find much data on this or an explanation that is collectively agreed upon. In particular for drug studies, some people say that the drugs or metabolites get into the portal circulation of the liver, while other people say that the drugs are absorbed by the peritoneum and enter the systemic circulation via the lymphatic system? Some individuals would argue that substances diffuse across the peritoneal membrane and then make their way into the interstitial fluid first, and then passively diffuse into the body's fluid compartments. Could it be another route? Could it be an active process or is it completely passive? Or, alternatively, could it be a combination of several of these processes?