Achieving efficient anti-adhesion in re-mediastinoscopy: an experimental study in rats.
OBJECTIVE
Re-mediastinoscopy can be a difficult procedure due to fibrosis in the mediastinum. We have investigated the effect of an anti-adhesive barrier agent "hylan B gel" on the formation of adhesions after dissection in the superior mediastinum in a rat model.


METHODS
The study was conducted in 70 male Sprague-Dawley rats weighing 300 g. The strap muscles were divided by a midline cervical incision. The anterior and lateral aspects of the trachea were dissected to the level of the carina. Hylan B gel (Sepragel Sinus, Genzyme Company, Redgefield, NJ, USA) was used to create an anti-adhesive barrier. The rats who were subjected to surgery were sacrificed on postoperative days 14 and 28. All rats were previously divided into 5 groups: Sham group (n = 10); Group 1 (n = 15) surgery alone, sacrificed on day 14; Group 2 (n = 15) surgery and Sepragel, sacrificed on day 14; Group 3 (n = 15) surgery alone, sacrificed on day 28; Group 4 (n = 15) surgery and Sepragel, sacrificed on day 28. Histopathological analysis was performed to study the effect of the anti-adhesive agent. Scores were calculated based on collagen fibrosis, fibroblasts, granulation tissue, muscle alterations/inflammation, histiocytes, mononuclear giant cells, inflammation and vascular proliferation.


RESULTS
Collagen fibrosis and fibroblast scores, which represent adhesions, were significantly higher in Groups 1, 2, 3, 4 than in the Sham group ( P < 0.01). The degree of adhesions on day 14 was found to be higher in Group 1 compared to Group 2 ( P < 0.01). Adhesions on day 28 were higher in Group 3 compared to Group 4 ( P < 0.01). There were no differences between groups with regard to foreign body reactions ( P > 0.05).


CONCLUSIONS
Adhesions causing technical difficulty during re-mediastinoscopy can be reduced by the application of anti-adhesive agents during the primary procedure.
Solak
O
O
Department of Thoracic Surgery, Kocatepe University, School of Medicine, Afyon, Turkey. okanchest@yahoo.com
Esme
H
H
Sirmali
M
M
Sahin
O
O
Agackiran
Y
Y
Bas
O
O
Emmiler
M
M
D000818:Animals; D020099:Coated Materials, Biocompatible; D004195:Disease Models, Animal; D005500:Follow-Up Studies; D008297:Male; D008477:Mediastinal Diseases / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D008481:Mediastinoscopy / Q000009:adverse effects / Q000379:methods*; D011126:Polypropylenes; D019919:Prosthesis Implantation / Q000295:instrumentation*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012720:Severity of Illness Index; D000267:Tissue Adhesions / Q000517:prevention & control; D016896:Treatment Outcome
D020099:Coated Materials, Biocompatible; D011126:Polypropylenes; C418228:sepramesh