Page 29 - Postoperative Intra-Abdominal Adhesions- New insights in prevention and consequences

Current status postoperative abdominal adhesions
Nonsteroidal anti-inflammatory drugs (NSAID’s)
A number of locally and systemically administered NSAID’s have been
tested in the experimental setting. They act by modifying arachidonic
acid metabolism by changing cyclooxygenase activities, inhibiting the 2 formation of end products, including prostaglandins and thromboxane.
This results in decreased vascular permeability, plasmin inhibitor,
platelet aggregation and coagulation and increased macrophage
function ultimately diminishing adhesion formation in most animal
studies. However, adhesion prevention with NSAID’s in humans is highly controversial because of inadequate concentrations at the sites of
surgical trauma or by rapid absorption from the peritoneal membrane. Additionally several side effects still have to be ascertained [6, 37, 44,
61, 62].
Corticosteroids and antihistamines
Corticosteroids diminish the inflammatory response by reducing vascular permeability and liberation of cytokines and chemotactic factors. Antihistamines inhibit fibroblast proliferation and stabilize lysosomal membranes and histamine secretion. Corticosteroids, such as dexamethasone, hydrocortisone, and prednisolone were studied alone or with antihistamines such as promethazine, by intraperitoneal administration [61, 62]. Nevertheless, results were varying and adverse events such as systemic immunosuppression, delayed wound healing and anastomotic leakage (e.g. infection, incisional hernia and wound dehiscence) argue that these agents should be used with extreme caution [37, 39, 60, 63, 64].
Progesterone/Estrogen
Progesterone has been investigated for reduction of postoperative adhesions after the initial observation that adhesions were reduced after ovarian wedge resection if that ovary was containing an active corpus luteum at the time of operation [65, 66]. This observation was validated in some animal models, whereas human studies have either failed to confirm this finding or noted an increase in adhesion formation when medroxyprogesterone acetate was used intramuscularly or intraperitoneally [61, 67]. Estrogen has been associated with increased
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