Hartikainen had a goal and two assists in 23 games with the Oilers. He also had 14 goals and 23 assists in 47 games with the Oklahoma City Barons this season.
Tuohimaa has played 32 games over the last two seasons with Jokerit in the Finnish Elite League.
He appeared in 13 games this past season and posted a 2.29 goals-against average and .912 save percentage. In two playoff games, he had a .960 save percentage and 0.77 GAA.
The Oilers selected Tuohimaa in the seventh round (No. 182 overall) of the 2011 NHL Entry Draft.