Thanks everyone for the kind wishes. It's been quite a rollercoaster lately.
My uncle is still in ICU, but yesterday, they were able to take him off the ventilator. This is quite a promising change since when he was admitted, his oxygen (at the highest) was only 60%. Goodness knows how he was having coherent conversations with the medical staff then. He had also developed a secondary opportunistic bacterial lung infection, which they have now cleared. His kidneys are unfortunately still in bad shape though. And shortly after admittance, he had a heart attack. They need to do further imaging on his heart and circulatory system, but he's too fragile to move right now and his kidneys are not strong enough (yet) to be able to process the dye they need to inject. They said he's not out of the woods yet, but there are some glimpses of sunshine through the trees now.
My mom is traveling this week, so she'll be there when they start to bring him back into consciousness (hopefully in several days, if his breathing remains okay). I'm so grateful she is able to get there.