Hi! Yes it’s narrative focused, so Guide & players decide: there’s no hit points or health points in the “traditional” sense.
You might be in a Tight Spot fighting a group of armoured guards. A PC wants to knock one guard out with a blow to the head. They must make a Luck Roll, which the Guide says has Disadvantage because the guard is wearing a helmet. If the PC still succeeds on their roll, they guard is rendered unconscious!
Here’s how a PC can fall unconscious. If they fail their roll to evade harm during a Tight Spot, if the Opponent is trying to knock them out, that just happens!
Also: Both in and out of a Tight Spot, because the Hurt condition causes Disadvantage on relevant Actions (increasing EP cost), a PC can become unconscious through sheer exhaustion if they receive so many stacked Hurt conditions that they end up spending all their EP.