Given the lack of clinical data of the efficacy of oxygen administration, European guidelines for the management of acute coronary syndromes do not now include a recommendation for supplemental oxygen[17]. Whilst the recent American Heart Association guideline for the management of acute coronary syndromes does recommend oxygen, they note that there is no clinical trial evidence to support this recommendation[4]. The most recent addendum to the 2006 Australian National Heart Foundation Guidelines does not recommend the routine use of supplemental oxygen[18].