Elgin Pearce and Kyle Becker also scored for Medicine Hat (10-9-1), which has won six of its last seven games. Sam Reinhart replied the Ice (4-11-1), who lost their seventh in a row.
Pearce, who was traded from Kootenay to Medicine Hat earlier this season, opened the scoring on a rebound of a Curtis Valk shot at 15:12 of the first period. Becker made it 2-0 with a power play goal at 10:14 of the second period before Reinhart responded for Kootenay with a backhand tally with a minute left in the period.
Shinkaruk put the game out of reach with a power play goal at 19:38 of the third period.
Cam Lanigan made 27 saves for the Tigers.
Mackenzie Skapski stopped 34 shots for Kootenay.