US in-patient costs are about double that of the European average.
An ICU bed that is $1,000 per day in Europe, is around $2,000 in the US.
But the hospital will have a charge master price of $10,000 per day.
Insurance company negotiate agreed charges that are often 80-90% lower.
That’s the number that contributes to GDP.
Anyway, that's another topic and you are right that for the GDP purposes the spent per capita is a good metric. Which is still on the point, the same service costs at least twice as much resulting in useless numbers if you are trying to use GDP as a productivity metric(or anything humane, in fact).
We see a similar thing in Turkey for example when you use PPP(which is supposed to be an improvement). Turkey's PPP is quite high now, meaning that the Turkish lira is strong and on average Turks are supposed to be slightly richer than neighboring EU country Bulgaria. In reality, Turks are miserable because some basic stuff is taxed to extremes and the market is captured by a few groups and to achieve a Bulgarian lifestyle in Turkey you actually have to pay 2X or 3X.
Maybe we just should stop looking and these stats for a proxy to other stuff altogether. They don't work, just use whatever you are looking directly.