GSTM1 and Multiple Organ Failure: Even a timely diagnosis is made, the management of acquired severe Met-Hb is still challenging, regardless methylene blue is available or not.[4–7] It would usually be fatal due to persistent hypoxemic injury and multiple organ failure despite of maximal ventilator support especially when the antidote is not delivered timely.[4–7] In addition to the conventional treatments reported in the previous literature, VV-ECMO can be used as a bridging therapy before antidote arrives to minimize hypoxemic injuries.