A lot of the beds are used for routine scheduled stuff that can be postponed. While the ER/ICU/telemetry capacity is much smaller (can’t find online source but it’s about 150 beds in Stanford), these are usually reserved for postop and ER flow (car accidents, etc.). Plus there are expansion possibilities. Overall, there about 500-1000 beds for critical care in Santa Clara that can be made available (I also suspect there are not that many car accidents, broken legs, etc right now). Overall, we are at about 10x in available capacity right now.

Edit: source is my wife who used to be ER nurse and then ER nurse manager in several Bay Area hospitals.