The Care Quality Commission has demanded immediate improvements at Plymouth Hospitals Trust.
An inspection to Derriford Hospital, run by Plymouth Hospitals NHS Trust, found that check-lists recommended by the World Health Organization and the National Patient Safety Agency were not being fully completed by surgical teams across some operating theatres.
The trust has been told it is critical that these key checks are completed without exception, as failure to do so may result in an increased risk to patient safety.
The CQC has required that the trust addresses this issue immediately and has put in place steps for it to do so.
If the trust does not demonstrate full and consistent compliance with safety check lists from this point forward it may be subject to prosecution or closure of services.
The NPSA issued a national patient safety alert in January 2009, requiring all healthcare organisations to implement the WHO surgical safety checklist for every patient undergoing a surgical procedure by February 2010.