I really don't know why the ascites has shifted to one side. It may just be contained in a "pocket." I had a pocket of fluid in my midriff following hernia repair. I kept having to get drains as they would clog up. But it was just in one area and plainly visible on CT that it was in a pocket. Just a possibility for your dad.
The BP is much more concerning! Please continue to have someone take it this evening and even during the night. If it decreases any more, don't hesitate to call Rescue.
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"But that was yesterday, and I was a different person then."
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