What causes a hemotoma from a hernia wound?

Incisional bleeding : A hematoma associated with a surgical incision would typically occur due to small amount of bleeding under the staples or sutures shortly after closure. It can keep that section of skin and tissue from healing as quickly as it should and could cause a small opening that will need wound care to heal more slowly.

Bleeding: A hematoma is simply a collection of blood under the skin. This can occur after surgery if one is taking blood thinners, such as aspirin. Can also occur if bleeding is not adequately controlled during the surgery. Direct trauma to an incision soon after surgery can also cause a hematoma. Most common cause is the use of blood thinners.