Page 73 - Postoperative Intra-Abdominal Adhesions- New insights in prevention and consequences

Adhesion barrier and colon anastomoses
was considered to be the ABP. After measurement of the ABP, animals were sacrificed.
Adhesions around the anastomosis were evaluated in two steps. First, the amount of adhesions was measured by determining the percentage of the anastomosis covered with adhesions. Then, the extent and characteristics of adhesions was scored according to the system of van der Ham et al.20, which is presented in table 1.
Table 1. Scoring System According to van der Ham et al. [20] 4 Score Extent and characteristics of adhesions
0 No adhesions
1+ Minimal adhesions, mainly between anastomosis and omentum
2+ Moderate adhesions; i.e., between omentum and the anastomotoc site and between the anastomosis and a loop of small bowel
3+ Severe and extensive adhesions, including abscess formation.
One centimeter colon with the anastomosis in the middle was excised and evaluated histopathologically. The tissue was processed according to the method of Creemers et al21. A colorimetric hydroxyproline assay was performed to determine the amount of collagen in the anastomotic tissue samples, as hydroxyproline is a collagen-specific amino acid. Samples were first treated with 6N acid hydrolysis, followed by chloramine-T to oxidize hydroxyproline into pyrrol. Pyrrol was converted into a chromophore (red) by dimethylaminobenzaldehyde. Using a wavelength of 570nm the amount of red colour reflects the amount of hydroxyproline, assuming 300 hydroxyproline residues per collagen triple helix.
Statistics
The normality of the data was determined by means of the Shapiro- Wilk test and visual assessment. Categorical data (adhesion scores) are presented as numbers with percentages, and numerical data are presented as means with standard errors of the mean (normally distributed) (SEM) or medians with interquartile ranges (not normally distributed). Differences between groups were assessed using an Χ2 test for categorical data (adhesion scores) or an unpaired t-test (normally distributed) or Mann-Whitney U test (not normally distributed) for numerical data.
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