Dean's first thought, as he helped haul Sam onto the ground, was to get him back in the Impala, in the warm. He looked freezing, and was shivering badly. At the mention of the body however Dean looked over in the direction of where Sam was pointing.
Sure enough, there was a body, pale and lifeless skin, with sunken in eyes, open wide and staring upwards. It seemed like they had found one of their missing persons. The cause of death was not obvious from where he was, however he could see no obvious wounds, as with the animal attacks, and he was guessing that if he looked close enough there would be puncture marks on the neck.
He looked back at Sam, who looked like a drowned rat, his clothes soaked and sticking to his skin, still shivering and cold. They should probably check the body out later. Get Sam in some dry clothes and in the warm, before he made himself ill.
"We should go back to the Impala," Dean commented, grabbing hold of Sam's arm, and dragging him towards where the way up was. Hopefully they would be alright getting back up the bank.