I think anyone up for more than 24 hours will have "slept" a little, not knowing it. Microsleep. By catnap, do you mean lying down and shutting your eyes, intending to rest/sleep?
My obligatory sleep deprivation story:
I was in Las Vegas, and it was my last day there after a weeklong stay so I had to make the most of it. I got up hung over early Saturday morning, went to the remaining places and sights I wanted to see and came back to my hotel early evening.
My plane leaves early Sunday morning, so I don't intend to go to bed, risking oversleeping. Instead I play poker all night, seeing staff shift changes and the ebb and flow of players. Dawn breaks and I go to my room and get my luggage. Obligatory cockup: Leaving, I put my keycard on the bed and put my big suitcase by the door in the corridor, intending to make a last sweep of the room. The travel/hotel narrative requires that the door clicks closed and locked behind me... Down to the lobby, get a new card, up and get the luggage.
I make a domestic flight and then a transatlantic flight. I'm back in Sweden Monday morning, I think. I didn't sleep on the plane, per se. Just zoned out sometimes but it was never shuteye time. Let's say approx. 48 hours without lying down.
I stay at my sister's place two nights (severely zonked) and I'm finally home Wednesday.
"I'll just rest on the couch a little and then unpack." I wake up with the TV on - "Oh, hey, CNN. I have that at home too. My bags are there waiting for me but I still have dollars left, let's go down to the tables for one last round. Except... Oh, I'm home?"