The Effect of Heparin Upon Intra-Abdominal Adhesions in Rabbits

Abstract

IT IS GENERALLY RECOGNIZED that certain patients form intra-abdominal adhesions after operation or after inflammatory processes. These may produce intestinal obstruction, and at times require surgery. Often adhesions reform and, again, cause obstruction. Methods that might prevent formation or reformation of adhesions have been the subject of several investigations adequately reviewed by Boys1 in I942. Certain of these methods have been of general interest. Rea and Wangensteen,2 Gepfert,3 Totten,4 Merkle,5 and others, introduced amniotic fluid, saline, air, oil, glucose, blood, gum acacia, etc., into the peritoneal cavity to mechanically separate damaged surfaces until reepithelization might occur. Ochsner and Garside,6 Donaldson,7 Ward,8 and others, tried proteolytic enzymes, such as papain or trypsin to digest deposits of fibrin. Lehman and Boys9' 10 employed heparin to minimize the formation of fibrin. Clinical reports of the use of papain by Ochsner,'1 and of heparin by Lehman and BoyS12' 13 and Massie,14 have offered encouragement, but the results are not easily evaluated. Experiments have, therefore, been undertaken to further study the effect of heparin upon the formation and reformation of adhesions. Rabbits, usually male, have been used for all experiments. EXPERIMENTAL METHODS Operations for Prodtuction of Adhesions: Rabbits were anesthetized by intravenous sodium amytal. A midline incision was made, using sterile technic. The appendix was exposed and freed from the meso-appendix using fine silk No. oooooo, for ligation of vessels. The antimesenteric surface was then seared by applying a thin, heated spatula. The peritoneum and the incision were closed by a continuous mattress suture of either fine silk or catgut. The skin was closed with interrupted silk. Operations were performed by several individuals employing this standard technic. Operations for Division of Adhesions: Celiotomies were performed through the same midline incision two weeks, or more, after the searing and at varying intervals thereafter, to determine occurrence and extent of adhesions and to divide and study reformation of adhesions. Adhesions were divided, using blunt dissection for closely adherent surfaces or sharp dissection with division and ligation for longer bands.