The Daily Telegraph has reported that at least 52 staff have been silenced using the orders since 2008, some of which cost as much as £500,000.
Tory MP Steve Barclay, who obtained the figures, has called for Sir David Nicholson, the chief executive of NHS England, to stand down:
It is simply not plausible that the man who was supposed to be running the NHS was seemingly unaware that employees threatening to speak out were being offered golden goodbyes in return for a vow of silence.
The culture in the NHS needs to change, he has to stand down now. What patient safety concerns have been covered up (by these gagging orders)? How many lives have been put at risk?
More top news
Former cricketer Andrew Flintoff and Tony Blair's ex-spin doctor Alastair Campbell talk about mental health battles in a series of films.
Row over apparent threat to security co-operation with the EU unless it agrees to a trade deal is a "misunderstanding", a minister has said.
The north and west of the country will see rain, while southern and eastern areas will get warm sunshine.