Police became involved after two whistleblowers raised allegations of medical negligence at two of the trust's departments - neurosurgery and general surgery, including concerns about at least 40 deaths.
The increase in cases is linked to more families having contacted the police.
Separate to this investigation, we have spoken to the family of a patient who allege they were "lied" to by a senior surgeon in the trust's general surgery department, before he carried out an operation that left her with life-threatening injuries.
Wendy Gibbs, 80, had been due to be operated on by Marc Lamah to repair a pelvic prolapse at a private hospital in Brighton, run by Nuffield Health. But the surgeon told her he wanted to switch the procedure to a different Nuffield hospital because the Brighton site didn't have a specific type of scanner that he would need. The machine, it turned out, was also not available at the second hospital.
Mr Lamah also failed to disclose to Mrs Gibbs that he, and other surgeons, were prevented from carrying out such operations in Brighton at the time, as Nuffield Health had suspended that type of surgery over safety concerns.