Final answer:
After performing defibrillation with 120 J, the next intervention would be to assess the patient's condition and continue providing appropriate medical care.
Step-by-step explanation:
In order to bring a patient out of cardiac arrest using a defibrillator, the next intervention after performing defibrillation with 120 J would be to assess the patient's condition and continue providing appropriate medical care. Defibrillation is a procedure that delivers a high-energy electric shock to the heart in order to restore normal electrical activity. After the initial shock, medical professionals will monitor the patient's vital signs, administer medications if necessary, and provide ongoing support and treatment to stabilize the patient's condition.