Complex sentence: Hank offers to slit his own wrist, ostensibly because of Dale's squeamishness at the sight of blood, using this ruse to get his pocketknife so that he can cut himself free.
Split into simpler sentences: Hank offers to slit his own wrist, ostensibly because of Dale's squeamishness at the sight of blood. He uses this ruse to get his pocketknife so he can cut himself free.