The role of neutrophils and oxygen free radicals in post-operative adhesions.
BACKGROUND
Postoperative intra-abdominal adhesion formation remains a major surgical problem. Surgery induces an inflammatory reaction, which is responsible for adhesion formation. Neutrophils and their oxygen-free radicals are key mediators in the early post-operative inflammatory response. The present study evaluates the effect of either blocking the influx of neutrophils or its products by scavenging oxygen-free radicals on adhesion formation.


METHODS
Reproducible rat models were used to induce post-surgical intra-abdominal adhesions. In the first experiment anti-neutrophil serum (ANS) was used to prevent neutrophils from entering the peritoneal cavity after surgery. In a second experiment superoxide dismutase (SOD), catalase, and mannitol were tested, to scavenge the superoxide, hydrogen peroxide, and hydroxyl radicals, respectively.


RESULTS
In positive control groups 69 to 76% of the area of interest contained adhesions. In all experimental groups, except for mannitol, a significant reduction in post-surgical adhesion formation could be achieved. ANS reduced adhesion formation by 38% (P < 0.001) and SOD/catalase by 42% (P < 0.01). Mannitol could not reduce adhesion formation.


CONCLUSIONS
Intra-abdominal influx of neutrophils after surgical peritoneal trauma plays an important role in post-operative adhesion formation. Preventing the intra-abdominal influx of neutrophils in the early post-operative inflammatory reaction can reduce adhesion formation, but an even more selective approach, by scavenging its products, proved as efficient.
ten Raa
Sander
S
Department of General Surgery, ErasmusMC, Rotterdam, The Netherlands. sandertenraa@hotmail.com
van den Tol
M Petrousjka
MP
Sluiter
Wim
W
Hofland
Leo J
LJ
van Eijck
Casper H J
CH
Jeekel
Hans
H
D000818:Animals; D017209:Apoptosis / Q000276:immunology; D002455:Cell Division / Q000276:immunology; D045304:Cytochromes c / Q000378:metabolism; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D009504:Neutrophils / Q000166:cytology / Q000276:immunology* / Q000378:metabolism*; D009852:Omentum / Q000166:cytology; D017395:Plasminogen Activator Inhibitor 1 / Q000378:metabolism; D011183:Postoperative Complications / Q000276:immunology / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D017382:Reactive Oxygen Species / Q000378:metabolism*; D000267:Tissue Adhesions / Q000276:immunology* / Q000378:metabolism*; D010959:Tissue Plasminogen Activator / Q000378:metabolism
D017395:Plasminogen Activator Inhibitor 1; D017382:Reactive Oxygen Species; D045304:Cytochromes c; D007770:L-Lactate Dehydrogenase; D010959:Tissue Plasminogen Activator