title: Supplemental oxygen delivery to suspected stroke patients in pre hospital and emergency department settings.
abstract: BACKGROUND
  Recent data suggests that high-flow oxygen started promptly after stroke symptom onset salvages ischemic brain tissue. We investigated the consistency of oxygen delivery to suspected stroke patients in the pre-hospital (PH) and Emergency Department (ED) settings, and associated adverse events (AEs).
  
  
  METHODS
  We retrospectively reviewed pre-hospital call reports of suspected stroke patients transported by our institution's paramedics. We extracted data on oxygen delivery in the PH and ED settings, demographics, Glasgow Coma Scale score (GCS), final diagnosis, and selected AEs (mortality, seizures, worsening neurological status, new infarction, and post-ischemic hemorrhage). Patients were grouped according to ED oxygen delivery: none, low-flow (2-4 L/min), and high-flow (10-15 L/min).
  
  
  RESULTS
  Oxygen delivery was documented in 84% of 366 stroke transports, with 98% receiving 10-15 L/min. Our hospital received 164 patients. Oxygen delivery in the ED was documented in 150 patients, with 38% receiving none, 47% low-flow, and 15% high-flow oxygen. There were no instances of oxygen refusal, premature termination, or technical difficulties. Advanced age and low GCS predicted the use of higher flow rates. High-flow oxygen was more frequently administered to patients with symptom onset < 3 hours, and those with intracerebral hemorrhage (ICH), hypoxic-ischemic encephalopathy (HIE) or seizures (p < 0.001). More patients receiving high-flow oxygen were documented to have an AE (p = 0.02), however the low- and no-oxygen groups more frequently had multiple AEs (p = 0.01). The occurrence of AEs was predicted by the diagnosis of ICH/HIE/seizures (p = 0.013) and acute ischemic stroke (AIS)/transient ischemic attack (TIA) (p = 0.009), but not by the amount of oxygen.
  
  
  CONCLUSIONS
  Suspected stroke patients routinely receive 10-15 L/min oxygen in the ambulance however in the ED there is wide variability due to factors such as clinical severity. Oxygen delivery appears safe in the PH and ED settings.
authors.affiliation: Department of Emergency Medicine, Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, 19 East 98th Street, 3rd Floor, New York, NY 10029, USA ; Genetics and Genomic Sciences, Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, 19 East 98th Street, 3rd Floor, New York, NY 10029, USA.
authors.forename: Yu-Feng Yvonne
authors.initials: YF
authors.lastname: Chan
authors.affiliation: Department of Neurology, University of California, San Francisco (UCSF) Medical Center, 1635 Divisadero Street, Suite 520, San Francisco, CA 94115, USA.
authors.forename: Maya
authors.initials: M
authors.lastname: Katz
authors.affiliation: Department of Medicine, Division of Pulmonary and Critical Care Medicine, Massachusetts General Hospital, 55 Fruit Street, Boston, MA 02114, USA.
authors.forename: Ari
authors.initials: A
authors.lastname: Moskowitz
authors.affiliation: Department of Neurology, State University of New York (SUNY) Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY 11203, USA.
authors.forename: Steven R
authors.initials: SR
authors.lastname: Levine
authors.affiliation: Department of Emergency Medicine, Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, 19 East 98th Street, 3rd Floor, New York, NY 10029, USA.
authors.forename: Lynne D
authors.initials: LD
authors.lastname: Richardson
authors.affiliation: Department of Neurology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA.
authors.forename: Stanley
authors.initials: S
authors.lastname: Tuhrim
authors.affiliation: Department of Neurology, Massachusetts General Hospital, 55 Fruit Street, Boston, MA 02114, USA.
authors.forename: Kevin
authors.initials: K
authors.lastname: Chason
authors.affiliation: Personalized Medicine and Digital Health, Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, 19 East 98th Street, 3rd Floor, New York, NY 10029, USA.
authors.forename: Kelly
authors.initials: K
authors.lastname: Barsan-Silverman
authors.affiliation: Genetics and Genomic Sciences, Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, 19 East 98th Street, 3rd Floor, New York, NY 10029, USA.
authors.forename: Aneesh
authors.initials: A
authors.lastname: Singhal