title: Hospitalized children with 2009 pandemic influenza A (H1N1): comparison to seasonal influenza and risk factors for admission to the ICU.
abstract: BACKGROUND
  Limited data are available describing the clinical presentation and risk factors for admission to the intensive care unit for children with 2009 H1N1 infection.
  
  
  METHODS
  We conducted a retrospective chart review of all hospitalized children with 2009 influenza A (H1N1) and 2008-09 seasonal influenza at The Children's Hospital, Denver, Colorado.
  
  
  RESULTS
  Of the 307 children identified with 2009 H1N1 infections, the median age was 6 years, 61% were male, and 66% had underlying medical conditions. Eighty children (26%) were admitted to the ICU. Thirty-two (40%) of the ICU patients required intubation and 17 (53%) of the intubated patients developed acute respiratory distress syndrome (ARDS). Four patients required extracorporeal membrane oxygenation. Eight (3%) of the hospitalized children died. Admission to the ICU was significantly associated with older age and underlying neurological condition. Compared to the 90 children admitted during the 2008-09 season, children admitted with 2009 H1N1 influenza were significantly older, had a shorter length of hospitalization, more use of antivirals, and a higher incidence of ARDS.
  
  
  CONCLUSIONS
  Compared to the 2008-09 season, hospitalized children with 2009 H1N1 influenza were much older and had more severe respiratory disease. Among children hospitalized with 2009 H1N1 influenza, risk factors for admission to the ICU included older age and having an underlying neurological condition. Children under the age of 2 hospitalized with 2009 H1N1 influenza were significantly less likely to require ICU care compared to older hospitalized children.
authors.affiliation: Department of Pediatric Critical Care, The Children's Hospital, University of Colorado School of Medicine, Aurora, Colorado, United States of America.
authors.forename: Dayanand
authors.initials: D
authors.lastname: Bagdure
authors.forename: Donna J
authors.initials: DJ
authors.lastname: Curtis
authors.forename: Emily
authors.initials: E
authors.lastname: Dobyns
authors.forename: Mary P
authors.initials: MP
authors.lastname: Glodé
authors.forename: Samuel R
authors.initials: SR
authors.lastname: Dominguez
mesh_terms: D000998:Antiviral Agents / Q000494:pharmacology; D002648:Child; D015331:Cohort Studies; D003120:Colorado; D003422:Critical Care; D005260:Female; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000235:genetics*; D007251:Influenza, Human / Q000235:genetics* / Q000821:virology*; D007362:Intensive Care Units; D008297:Male; D010100:Oxygen / Q000737:chemistry; D012189:Retrospective Studies; D012307:Risk Factors; D012621:Seasons
chemical_list: D000998:Antiviral Agents; D010100:Oxygen