Page 291 - Prevention and Treatment of Incisional Hernia- New Techniques and Materials

Exact methods for signi cance were used when computational limits allowed these. All reported P values are 2-sided and considered signi cant if less than 0.05. In view of the small sizes of the groups, it was not possible to adjust the P values using the Bonferroni correction. Statistical analysis was performed using PSAW statistical software package, version 17 (IBM SPSS statistics).
Results
During the 2 days after implantation of the mesh, 18 of the 90 rats (20%) were prematurely taken out of the experiment because of a low wellness score. Postoperative mortality was not statistically di erent between the groups. In all rats necropsy was performed and septicemia was found to be the cause of death. Abdominal cultures at day 1 con rmed bacterial contamination in all animals with gram-positive (Enterococcus, Staphylococcus, Streptococcus) and gram-negative microorganisms (Escherichia coli and Proteus). All animals demonstrated signs of sepsis including apathetic behaviour, ocular exudates, piloerection, diarrhea, and weight loss. Mortality in the groups is depicted in Table 1. Maximum percentage weight loss was signi cantly higher in CollaMendFM after postoperative day 5 compared with the other groups (median: CollaMendFM, 12%; Strattice, 11%; Surgisis, 9%; Permacol, 9%; P < 0.020).
Table 1. postoperative mortality and animals analysed at both time points per group.
Group
Control Strattice Surgisis Permacol CollaMendFM Total
Material
No mesh
Non-crosslinked dermis Non-crosslinked submucosa Crosslinked dermis Crosslinked dermis
Animals Postoperative mortality
18 2 18 4 18 5 18 5 18 2 90 18
90 days
8 7 6 7 9 37
180 days
8 7 7 6 7 35
14
Infection susceptibility of biological meshes
*One rat in the Permacol group and 7 rats in the CollaMendFM group were euthanized before the intended end point. The results of these rats were analyzed together with the rats sacri ced at the intended end point.
Mesh infection and abdominal abscesses
Seven animals (44%) with a CollaMendFM mesh and 1 animal (7%) with a Permacol mesh were euthanized before the intended time point because
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