Medtronic announced that on May 8, 2015, it began notifying hospitals and distributors worldwide that affected lots of its Covidien Shiley tracheostomy tubes were formed with a wider-angle bend than standard models manufactured after November 29, 2012. The company initiated the field action following customer complaints that included reports of 12 serious patient injuries, such as breathing difficulties that impacted oxygen levels, immediately upon tube placement or discomfort. Replacement of the tracheostomy tube with product manufactured prior to November 29, 2012 addressed the patient breathing difficulty or discomfort.