The U.S. Food and Drug Administration is monitoring about 50 kinds of medical devices manufactured in Puerto Rico to make sure that the ongoing failure of the island's power grid following recent hurricanes doesn't trigger shortages of much-needed health supplies.

In particular, the FDA is working closely with about 10 companies to prevent shortages of products across the U.S., with a specific focus on "blood-related" medical devices. Some of the 10 companies are the sole suppliers of their devices, though the FDA didn't identify the companies or products.

"Puerto Rico's device industry is facing the same basic — but significant — challenges as most manufacturing sectors in Puerto Rico: a lack of power; connectivity; transportation; and clean water," FDA Commissioner Dr. Scott Gottlieb said in a statement Friday.

"Most, if not all, of these medical device manufacturers continue to run on generator power, and as a result, have been unable to return to pre-hurricane production levels."

Gottlieb addressed similar impacts to the pharmaceutical and biotech industries in Puerto Rico in an Oct. 6 statement.

Puerto Rico was still addressing impacts from Hurricane Irma when Hurricane Maria made a direct hit on the island on Sept. 20, knocking out the power grid and shutting down critical hospitals and roads. A month later, more than 80 percent of the territory is still without power

The U.S. territory is home to more than 18,000 people who work at upward of 50 different medical device plants around the island, including manufacturing sites owned by companies with major presences in the Twin Cities like Abbott Laboratories, Boston Scientific and Medtronic.

Their plants sustained varying levels of damage. Medtronic, which has four major production facilities that make products for each of its four product divisions on the island, recently reopened its plants at partial capacity using generator power. But the company has said the storm is expected to decrease sales by as much as $250 million during the quarter, and there's no firm timeline for when the factories will return to pre-storm production levels.

Medtronic CEO Omar Ishrak visited the island on Oct. 13, meeting with employees and posing for photos like one at the child care center at Medtronic's Juncos facility that was posted on Twitter.

"Visited MDT Puerto Rico facilities Friday. Inspired by employees' dedication & commitment. Great to see operations ramping up at all sites," Ishrak wrote on Twitter on Oct. 15.

Joe Carlson • 612-673-4779