Page 88 - Postoperative Intra-Abdominal Adhesions- New insights in prevention and consequences
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Chapter 5
Day 14: sacrifice. The animals were anesthetized using isoflurane/O2 by inhalation and shaved. After disinfection, the ventral abdominal wall was opened through a U-shaped incision, and a swab of the abdominal cavity was taken. The amount and tenacity of the adhesions was scored, and pictures were taken (5.0-megapixel digital camera; Sony Cybershot®, Tokyo, Japan). The abdominal cavity was inspected for abscesses, which were scored and cultured when found. The animal was then euthanized by cardiac cut.
Measurements
Wellness and survival. During the experiment, animals were weighed daily and scored for their wellness using an objective 12-point scoring system [24]. Animals with a weight loss of 20% or more or a wellness score of < 5 were euthanized. A necropsy was performed on all euthanized and deceased animals.
Adhesions. Two independent observers assessed adhesion coverage of the surface of the abdominal wall defect in a blinded manner using a scoring system, dividing the defect into four squares of 0.5 x 0.5 cm (0%, 1%–25%, 26%–50%, 51%– 75%, or 76%–100%) and categorized the tenacity of the adhesions using the objective Zühlke score [24], which is based on histologic and morphologic criteria (Table 1). In case of inter-observer disagreement, the mean Zü̈hlke score was calculated. The amount of adhesions (between viscera or between viscera and the abdominal wall, including the midline scar) was scored and the severity of the adhesions was graded by the Zühlke score.
Table 1. Zühlke score: macroscopic classification of abdominal adhesions.
Zühlke type 1
2
3 4
Characteristics
Filmy adhesion, easy to separate by blunt dissection
Stronger adhesion; blunt dissection possible, partly sharp dissection necessary; beginning of vascularization
Stronger adhesion; lysis possible by sharp dissection only; clear vascularization
Very strong adhesion; lysis possible by sharp dissection only; organs strongly attached with severe adhesions; damage of organs hardly preventable
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