No Suture Surgery?

My sister just had an open procedure for a repair of a strangulated hernia involving her small intestine.  I've searched all over the internet and can't find any information in regards to the surgeon left her incision completely open.  Her surgical site is approximately 5 to 6 inches long and about an 1 to 1 1/2 inches wide.  I'm cleaning her incision area with a saline wash and then packing the area with a saline drenched gauze.  I then place a long pad on top of that and tape it.  She's due back at the hospital in three weeks for a post-op check-up, but the more I think about it, the more I don't understand why her incision site wasn't at least taped back using surgical and suture tape.  How can the incision ever close if I'm packing the incision area with gauze?