By definition, cardiac arrest means the heart is not pumping blood; therefore, there is no blood pressure. None at all. So if you were to cut a person in cardiac arrest, they would not bleed.
If a heartbeat can be restored, the findings after cardiac arrest will vary. In general, if a normal heartbeat can be restored and the heart is once again pumping effectively, vital signs such as blood pressure should return to normal or near-normal levels fairly quickly. However, everything that was wrong with the patient before the arrest will still be present, so if they had hypertension before the arrest, they will probably have it afterwards. However, the cause of the arrest may have been a heart attack that left heart tissue damaged, and that might result in lower BP.
In short, there is no single answer as to what the pressure will be afterwards. It will depend on many things.