Is it possible you transposed those numbers? If that's what the doc said, he's completely misinformed. It's not quite the same number, but mortality after colectomy in the US is less than one percent.
I can't imagine a scenario where mortality reaches 95% in six months -- unless the colon is being removed with a rusty spoon in filthy conditions with no antibiotics afterward.
There are a lot of factors at play, and perhaps in Taiwan total colectomy is generally reserved for older patients with advanced colon cancer or something like that. Otherwise, I wouldn't worry about 5% survivability.