Two different poly(vinyl alcohol)-based gels (A-Part Gel) were compared and evaluated as possible adhesion prophylaxis gels. The gels were implanted to act as a physical barrier-and thus to prevent adhesions-in a rabbit sidewall model. The absorption time of any adhesion barrier is a critical parameter, since the wounded tissue needs to be covered during the healing process. Crosslinking by freeze-thawing helped to prolong the absorption time of the gels. To better understand the in vivo absorption, the gels were investigated in various physical in vitro methods such as decay measurements and experiments performed in a Soxhlet extraction thimble. The in vivo applicability of the gels by surgeons was judged in squeezing force measurements. The ability to cover the wounded area securely was measured with simple spreading experiments. Both gels could be squeezed out of the syringes easily and showed a homogenous spreading behavior. Comparing the two gels, the results of the in vitro absorption experiments were contradictive. Further, in vivo tests with correlations to the proposed in vitro measurements will reveal the correct interpretation. Nevertheless, the results in a pilot rabbit sidewall model were excellent for both A-Part gels, but only one gel was chosen for extended studies, showing only 20% adhesions when compared with the control group showing 100% strong adhesion formations. These data will be evaluated in other studies, and the use of an A-Part PVA-CMC gel for adhesion prevention has to be supported in clinical studies.
Copyright 2006 Wiley Periodicals, Inc.