Effects of Intra-Abdominal Drainages on Adhesion Formation and Prevention by Phospholipids in a Rat Model

Background and Aims: The study was designed to asses the adhesiogenic capacity of silicone drainages and the protective effect of phospholipids (PL). Materials and Methods: A total of 75 Wistar rats were randomly assigned to the different groups. In a preliminary trial (pt; n = 15), all rats underwent midline laparotomy. The control group (Cpt; n = 5) received no further treatment. In the other animals, either an ‘easy flow’ drainage (EFpt; n = 5) or an ‘Aachen’ drainage (ACpt; n = 5) was placed into the abdominal cavity. In the final study (fs; n = 60), rats underwent laparotomy and colonic anastomosis. The control groups (Cfs) received no drainages. In the other groups either one of the two types of drainages (EFfs, ACfs) were introduced. In 50% of the rats, 75 mg/kg of PL were administered intraperitoneally (Cfs+PL, EFfs+PL, ACfs+PL). The other rats received no additional treatment (CfsOPL, EFfsOPL, ACfsOPL). All animals were sacrificed 10 days after surgery. Areas of adhesions and anastomotic bursting pressures were measured (mean ± SD). Results: In the preliminary trial, analysis of variance (ANOVA) revealed no differences between the groups after application of drainages (values are given in mean ± SD): Cpt mean 23.3 ± 29.4 mm2, EFpt 829.7 ± 679.3 mm2, ACpt 609.9 ± 219.4 mm2. In the final study, 2-factorial ANOVA showed a significant effect (p fsOPL 140.6 ± 124.2 mm2, Cfs+PL 67.7 ± 60.4 mm2, EFfsOPL 1,217.0 ± 458.3 mm2, EFfs+PL 1,266.8 ± 368.3 mm2, ACfsOPL 861.7 ± 274.8 mm2, ACfs+PL 544.2 ± 193.8 mm2). Post hoc test for pairwise comparisons adjusted to Bonferroni showed significant differences (p fs 104.1 ± 92.3 mm2 vs. EFfs 1,241.9 mm2 ± 413.3 mm2; Cfs vs. ACfs 702.9 mm ± 234.3 mm2; EFfs vs. ACfs). Discussion: The final study demonstrates the adhesiogenic capacity of silicone drainage tubes in combination with anastomoses. Any protective effect of PL alone or in combination with drainages could not be shown. Conclusions: Indication for the use of drainages in standard surgical procedures should be reconsidered within the scope of their potential to cause adhesions and subsequent complications.