Effects of saline lavage temperature on peritoneal fibrinolysis and adhesion formation

Abstract

Peritoneal lavage with saline at room temperature causes peritoneal hypothermia, vasoconstriction, hypoxia, and acidosis, which are effects that are known to reduce fibrinolysis. Decreased fibrinolysis causes permanent adhesions. Normothermic lavage may prevent this deleterious process and reduce peritoneal adhesions. A rat model of cecal abrasion was used. Control animals received no medication while hypothermic or normothermic saline lavage were administered intraperitoneally to the experimental groups (n=24 for each group). Cardinal parameters of peritoneal fibrinolysis (tissue plasminogen activator [tPA] and plasminogen activator inhibitor type 1 [PAI-1]) were determined in peritoneal tissue samples on postoperative day 1, 3, and 10. On postoperative day 10, adhesions were graded. In the sham group (n=8), following laparotomy, peritoneal samples were taken to determine basal values of tPA and PAI-1 in healthy peritoneum. Cecal abrasion increased PAI-1 levels about tenfold on postoperative day 1 and caused adhesions. Normothermic saline lavage prevented this traumatic PAI-1 increase and stabilized it to baseline values throughout the experiment and reduced peritoneal adhesion formation. Hypothermic lavage also caused an inhibition of PAI-1 rise but adhesion, prevention was not significant. Our results suggest that normothermic saline lavage reduces adhesions by improving peritoneal fibrinolysis.