Most mortality estimates and forecasts include only deaths directly attributable to the virus. There are many indirect deaths that will be caused by it. Long term lung damage is one of the ways this will happen, probably among the most delayed. Many more deaths will happen because hospitals that are operating at capacity won't have the resources to prevent other deaths that they normally stop, or will have to stop non-critical treatments in ways that will reduce patients' life expectancies. I live in Madrid and know a neurologist that has stopped any intervention that can't be delayed.