title: Does permissive hypoxaemia during extracorporeal membrane oxygenation cause long-term neurological impairment?: A study in patients with H1N1-induced severe respiratory failure.
abstract: BACKGROUND
  The Extracorporeal Life Support Organisation accepts permissive hypoxaemia in adult patients during extracorporeal membrane oxygenation (ECMO). The neurological long-term outcome of this approach has not yet been studied.
  
  
  OBJECTIVE
  We investigated the prevalence of brain lesions and cognitive dysfunction in survivors from the Influenza A/H1N1 2009 pandemic treated with permissive hypoxaemia during ECMO for severe acute respiratory distress syndrome (ARDS). Our hypothesis was that this method is reasonable if tissue hypoxia is avoided.
  
  
  METHODS
  Long-term follow-up study after ECMO.
  
  
  METHODS
  Karolinska University Hospital, Sweden, from October 2012 to July 2013.
  
  
  METHODS
  Seven patients treated with ECMO for severe influenza A/H1N1-induced ARDS were studied 3.2 years after treatment. Blood lactate concentrations were used as a surrogate for tissue oxygenation.
  
  
  METHODS
  Neurocognitive outcome was studied with standardised cognitive tests and MRI of the brain.
  
  
  METHODS
  Cognitive functioning and hypoxic brain lesions after permissive hypoxaemia during ECMO. The observation period was the first 10 days of ECMO or the entire treatment period if shorter than 10 days.
  
  
  RESULTS
  Eleven of 13 patients were still alive 3 years after ECMO. We were able to contact seven of these patients (mean age 31 years), who all agreed to participate in this study. Mean ± SD peripherally measured arterial saturation during the observation period was 79 ± 10%. Full-scale Intelligence Quotient was within one standard deviation or above from the mean of a healthy population in five patients, and was 1.5 SD below the mean in one patient. In one other patient, it could not be determined because of a lack of formal education. Memory functioning was normal in all patients. MRI showed no changes related to cerebral hypoxia.
  
  
  CONCLUSIONS
  Permissive hypoxaemia during ECMO might not negatively affect long-term cognitive outcome if adequate organ perfusion is maintained.
  
  
  BACKGROUND
  at Clinicaltrials.gov NCT01763060.
authors.affiliation: From the ECMO Department Karolinska, Karolinska University Hospital and Department of Physiology and Pharmacology, Section for Anesthesiology and Intensive Care Medicine (BH, VvB), Department of Psychology, Karolinska University Hospital, Huddinge and Department of Clinical Neuroscience (CA) ECMO Department Karolinska (HK, KP, BF), Department of Neuroradiology, Karolinska University Hospital, Stockholm (MM), Department of Surgical Sciences, Radiology, Uppsala University (E-ML), Department of Surgical Sciences, Anesthesiology and Intensive Care and Hedenstierna Laboratory, Uppsala University Hospital, Uppsala (AL), Sweden.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Holzgraefe
authors.forename: Christin
authors.initials: C
authors.lastname: Andersson
authors.forename: Håkan
authors.initials: H
authors.lastname: Kalzén
authors.forename: Viktor
authors.initials: V
authors.lastname: von Bahr
authors.forename: Mikael
authors.initials: M
authors.lastname: Mosskin
authors.forename: Elna-Marie
authors.initials: EM
authors.lastname: Larsson
authors.forename: Kenneth
authors.initials: K
authors.lastname: Palmér
authors.forename: Björn
authors.initials: B
authors.lastname: Frenckner
authors.forename: Anders
authors.initials: A
authors.lastname: Larsson
mesh_terms: D000328:Adult; D015199:Extracorporeal Membrane Oxygenation / Q000009:adverse effects / Q000639:trends*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D000860:Hypoxia / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D053118:Influenza A Virus, H1N1 Subtype / Q000302:isolation & purification; D007251:Influenza, Human / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D012128:Respiratory Distress Syndrome / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors