Dear editor,rnA young lady in her early 20s presented acutely with shortness of breath with her oxygen saturations on room noted to be mid to 70％ with normal respiratory rate, and blue discolouration of the lips (Figure 1).rnThe relevant past medical history and surgical history included well controlled asthma and a laparoscopic salpingectomy for ectopic pregnancy approximately 3 weeks previously. The only relevant recent history was use of cocaine over the preceding 48 hours.