BOULDER COUNTY, Colo. (CBS4) — Centura Avista Adventist hospital, which was in the middle of the Marshall Fire evacuated 51 patients on Thursday. The building was spared from the flames, but the hospital will be closed indefinitely due to extensive smoke damage.

(credit: CBS)

“The high winds were driving the fire straight toward our hospital on the north side, so to return hours later and find no significant damage is truly a miracle,” said Isaac Sendros CEO for the hospital.

As those flames moved closer to the hospital, staff inside started evacuating critical patients first and protecting others until they could be moved as well.

“We moved everybody horizontally from the fire into the building on the far side to keep them safe,” Jennifer Wills said from inside the hospital’s medical surge unit.

(credit: Avista Adventist Hospital)

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Outside that unit was an even bigger concern. Massive liquid oxygen tanks were being threatened with every passing minute.

(credit: Avista Hospital)

“We were within feet of this being an extremely bad situation for the hospital,” Sendros said.

The worst was avoided thanks again to quick-thinking staff.

“Our facilities team did a tremendous job actually fighting this fire with water and hoses,” he said.

While the building itself was spared from the flames, being at the center of such a massive fire meant some damage was unavoidable.

(credit: CBS)

“You can see where all the filters were, you can see all the soot on the ground here,” Calvin Smith with the hospital said.

Heavy smoke that made its way inside, officials say will keep the facility closed for the foreseeable future.

RELATED: How To Help Residents Impacted By The Marshall Fire

On Friday, the hospital was relying on generators to keep the heat on.

In a statement released Friday, hospital officials say they will need to do a terminal clean, sanitize the hospital, evaluate the air quality and make sure surgical supplies are still useable before they can get things back open.

Karen Morfitt