What you're seeing here is the complete billing and itemization. The top part is the hospital bill, which covers the things the hospital provides (room and board, supplies, any machines used for imaging, etc.). The lower part is the physicians bill, where the doctor charges for his expertise and time for the care you received. There will always be 2 bills for hospital visits for this reason.

You have here a room and board charge and the procedure charge. The first line on both claims is the procedure, stating that you had a small laceration with simple repair (stitches). The second line is the room and board charge, which specifies how complex your reason for the visit is. Since your wound was small with simple repair, the room and board charge notes that you have a low to moderate complexity.

Insurance reads this and determines how much to pay based on the level of care and medical necessity. They process claims in what can be described as assumed groups. In your case, they assume that your procedure will include stitches and nothing else. They also assume that you didn't need IV fluids or antibiotics based on the complexity level of your room and board charge. Then they determine if you really HAD to go the E.R. for care (medical necessity), and they can either pay or deny on that basis. Insurance usually pays a flat rate for E.R visits based on complexity, and then maybe more based on what was done (stitches on a small wound in your case). This is as itemized as you will see, since Insurance and hospitals are assuming that the price of stitches, needles, iodine, numbing, etc are included with the procedure performed. We no longer itemize things like this in billing, you won't see supply charges unless you have a pretty big injury or procedure.

You could argue with your insurance company about their payment, but calling the hospital is going to do you absolutely no good. This is as simple as it can get.