If he has chrosis (sp) of the liver. You may never get that fluid. Better to tap him.. Hemodialysis takes fluid out of the blood.. And yes as you take fluid out of the blood other fluid from tissues will cross into the blood. You really shouldn't take fluid to vigorously from such an acutely ill patient. The body compensates and you have to take off fluid slowly. He should be dialyzed daily or you might suggest CVVH.. If you even have access to that modality.
WR,,, three commas for Becca.
Were you using the mannitol for B/P support? If so I'm not a fan of it. If B/P wasn't dropping no need to use Mannitol.