So the lower settings do not do nothing from 2 joules to 20 joulesTechnically, 7 joules is 7 joules (a unit of energy, same as watt-seconds), but we've pretty much settled on the notion that less energy delivered with a biphasic device can be as effective as more with a monophasic device. There are variables, though -- e.g., patient size, device, type of biphasic delivery. Also, whenever you see doses rounded to nice, neat numbers like 150 or 200, you can be sure there's some estimating going on. There's no evidence evolution favored the decimal system.
So the lower settings do not do nothing from 2 joules to 20 joules
Someone had tolsd me that the lower setting can be used on adultsUh, I guess I don't understand the question. Maybe I should have started by asking how you came up with 7 joules. If you're wondering whether low energy settings are ever used, the answer is yes, on peds, for whom electrical therapy is supposed to be weight related.
Is there a specific case you have in mind?
Someone had tolsd me that the lower setting can be used on adults