Medtronic PLC has recalled about 650 ventilators in the U.S. because a software glitch may cause the machines to deliver too little oxygen to neonatal patients. It was the second serious recall of the breathing device in a year.

The affected ventilator is called the Puritan Bennett 980 Ventilator System. The Food and Drug Administration announced Wednesday that Medtronic started notifying hospitals in July of the latest issue, which the agency classified a Class 1 recall because the lack of oxygen can lead to injuries or death.

The PB980 is a touchscreen-controlled critical care ventilator intended for adults, kids and premature babies. The device was approved by the FDA in February 2014, one year before Minnesota-run Medtronic acquired its maker, Covidien PLC.

No reports of serious patient harm have surfaced in the latest recall, according to Medtronic.

The manufacturer received reports from the field that a particular breathing setting on the ventilator — called Volume Control Plus Mode (VC+) — may not deliver as much oxygen as intended when used in combination with another setting that humidifies the air for neonatal patients.

Medtronic has been sending out service engineers to configure the ventilators and remove the NeoMode capability setting, but the company says the device remains safe for all of its other uses on adults and pediatric patients.

“The issue identified with the VC+ ventilation setting in NeoMode does not impact the PB980’s ability to deliver accurate volumes to pediatric and adult patients,” Medtronic spokesman John Jordan said in an e-mailed statement.

In October 2014, the FDA announced a Covidien recall of 324 of the same model ventilators. The FDA notice said ventilators with older software versions may have a glitch that caused the machine to stop working if the air and oxygen supply lines were disconnected and then reattached.

“This can lead to serious health problems or death if the health care provider does not connect the patient to another ventilator or to a different form of breathing support,” the FDA’s notice last year said.

Medtronic shares closed at $71.55 Wednesday, up $2.02, or 2.9 percent. The company is scheduled to report its first-quarter earnings Thursday.


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