05/13/2015 09:44 EDT | Updated 05/13/2016 01:12 EDT

Doctor tells inquest patient found unresponsive had no sign of injury

SAINT JOHN, N.B. - An emergency room doctor has told a coroner's inquest in Saint John, N.B., that a psychiatric patient found unresponsive in a hospital amphitheatre had no signs of injury.Dr. Paul Atkinson testified today before the five-person jury looking into the death of Serena Perry at the Saint John Regional Hospital on Feb. 14, 2012.Atkinson says he ran to the amphitheatre that night in response to a code blue call and found CPR already being performed on the 22-year-old.Atkinson says Perry was hooked up to a heart monitor around 11:15 p.m. and she was declared dead at 11:23 p.m.Atkinson told the jury he saw no injuries on Perry and couldn't see any place where she could have fallen or been hanged. Police have said a forensic pathology exam couldn't confirm the cause of Perry's death.