In the last 40 years I have seen 22lr stopped by heavy winter outerwear, jewelry, leather trucker wallets, small books, heavy leather vests (as is REAL motorcycle leathers, not cheap Pakistani black "look at me, I'm a bad man" leather jackets), and once even a skull. The bullet travelled between the skull and the scalp from the back of the head to the forehead before it stopped.
No 22lr (ESPECIALLY out of a short barreled pistol) for me unless there is ABSOLUTELY nothing else available. 380 with a very few loads IMO should be the minimum ever considered... and I would even take a BAD 380 round before a 22lr pistol.
I think it would be better than nothing. I was carrying a Kel-Tec P-32, with Hornady hollow points, but was never really comfortable that it was enough. I bought a Ruger LCP-MAX .380 one week ago. When I decide which ammo to carry in it I think I will be happy. It rides very well in my right front pocket in the pocket holster that came with it.