The jury has retired to consider its verdict in the manslaughter trial of former surgeon Jayant Patel.

In his summing up, Supreme Court Justice George Fryberg told the jury not to use hindsight in making its decision.

Patel is on trial in the Supreme Court in Brisbane, accused of the manslaughter of 75-year-old Mervyn Morris.

Mr Morris died of complications including heart and lung failure and septicemia after the former Bundaberg Hospital surgeon removed part of his colon in an attempt to address rectal bleeding in 2003.

Patel took the stand during the trial, insisting his decision to operate was appropriate.