A monitored patient in the ICU developed a sudden onset of narrow-complex tachycardia at a rate of 220/min. The patient's blood pressure is 128/58 mm Hg, the PETCO₂ is 38 mm Hg, and the pulse oximetry reading is 98. What is the most appropriate intervention in this situation?
1) Administer amiodarone 300 mg IV push
2) Administer adenosine 6 mg IV push
3) Perform synchronized cardioversion at 200 J
4) Perform synchronized cardioversion at 50 J