title: Influenza A (H1N1) patients admitted to intensive care units during the 2009 pandemics: clinical features and outcomes.
abstract: OBJECTIVE
  To describe the clinical features and outcomes of patients admitted with influenza A (H1N1) infection in two private hospitals' intensive care units in São Paulo, Brazil, during the 2009 pandemics.
  
  
  METHODS
  A retrospective cohort study was conducted to evaluate demographic data, initial clinical presentation, prognostic scores [Simplified Acute Physiology Score (SAPS) 3 and Sequential Organ Failure Assessment (SOFA)], comorbidities, outcomes and treatment of patients with confirmed pandemic influenza diagnosis from July to September 2009.
  
  
  RESULTS
  22 patients were admitted. Median age was 30 (25-43.5) years. Median SAPS 3 and SOFA were 42 (37-49) and 2 (1-3.5), respectively. Comorbidities were common (45.4%), especially obesity (22.7%). Two (9.1%) patients were pregnant. Five (22.7%) patients required invasive mechanical ventilation, with high positive end expiratory pressures (median of 16 cmH2O, interquartile range 10-25cmH2O). There was a 50% incidence of non-invasive ventilation failure. Most (77.2%) of patients were treated with oseltamivir. Hospital mortality was 4.5%. Initial SAPS 3, SOFA and PaO2/FiO2 ratio were associated with mechanical ventilation requirement (p<0.01).
  
  
  CONCLUSIONS
  Pandemic influenza infection mainly affected young and obese patients. In this study, patients were less severe than those previously described, what explains our low mortality and mechanical ventilation needs. However, high positive end expiratory pressures were required for mechanically ventilated patients.
authors.affiliation: Hospital e Maternidade São Camilo, Unidade de Terapia Intensiva Adulto, São Paulo, SP, Brasil.
authors.forename: Antonio Paulo
authors.initials: AP
authors.lastname: Nassar Junior
authors.affiliation: Hospital e Maternidade São Luiz, Unidade de Terapia Intensiva Adulto, São Paulo, SP, Brasil.
authors.forename: Amílcar Oshiro
authors.initials: AO
authors.lastname: Mocelin
authors.affiliation: Hospital e Maternidade São Luiz, Unidade de Terapia Intensiva Adulto, São Paulo, SP, Brasil.
authors.forename: André Luiz Baptiston
authors.initials: AL
authors.lastname: Nunes
authors.affiliation: Hospital e Maternidade São Camilo, Unidade de Terapia Intensiva Adulto, São Paulo, SP, Brasil.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Brauer