<qa>  What is the negative pressure system that holds the wound together?Dermabond and the Prevena Incision Management System are both FDA approved wound care products. Prevena is a negative pressure system which holds the wound together and removes exudate and debris from the site to prevent infection. Dermabond is a surgical glue which holds the wound together to prevents infection. Prevena is more expensive to apply. However, the hypothesis is that the Prevena System will decrease infection rates and therefore, decrease the ultimate cost of the health care needed after surgery. 