I never understood why it was recommended to give 100% oxygen to treat a pneumothorax. I think the idea was that the gas in the pneumothorax could be replaced by oxygen which would then be reabsorbed more quickly if we gave oxygen rather than air or another mixture with lower oxygen content and more nitrogen. But that would only work if the pneumothorax was being ventilated, and there was an open bronchopleural fistula, which is not usually the case. so we needed someone to examine the data.

This retrospective study shows absolutely no sign of an effect of giving 100% oxygen. Clark SD, Saker F, Schneeberger MT, Park E, Sutton DW, Littner Y. Administration of 100% oxygen does not hasten resolution of symptomatic spontaneous pneumothorax in neonates. J Perinatol. 2014.

Another therapy to consign to the garbage can of history.

Oxygen is toxic. Oxygen is life saving. Give only as much as you need to maintain ‘adequate saturations’ : whatever they are.