Is oxycodone the same as oxycotin. Can oxycodone given at 325mg cause hyperkalemia and cardiac arrest?

Same. Oxycontin is a brand name for oxycodone. It is a schedule ii controlled substance. The most common side effects are nausea, vomiting, dizziness or headache. Most serious side effect is respiratory depression or arrest. The "325" you mention is not the oxycodone dose. Must be the Acetaminophen (tylenol) content. Stay under 4000mg/day of Acetaminophen to avoid liver damage.
Same drug. Oxycontin is a longer release version. Usual dosage 10 to 80 mg tablets.