title: Phase angle as a prognostic marker in patients with critical illness.
abstract: BACKGROUND
  Phase angle (PA) is interpreted as an indicator of cell membrane integrity and a prognostic indicator in some clinical situations. This study aims to evaluate PA as a prognostic marker in critically ill patients admitted to the intensive care unit (ICU) and associate this marker with length of hospital stay, mortality, and clinical scores.
  
  
  METHODS
  A cohort study was conducted with 95 patients aged ≥18 years admitted to the ICU, who were assessed in terms of prognostic indexes (Acute Physiology and Chronic Health Evaluation II [APACHE II] and Sequential Organ Failure Assessment [SOFA]), clinical evolution (ICU discharge, death, and length of ICU stay), and PA.
  
  
  RESULTS
  Patients were predominantly male (63.1%) and had a mean age of 63.7 ± 14.6 years; length of stay of 4 days (range, 3-9 days); mortality of 15.8%; mean APACHE II and SOFA scores of 17.3 ± 8.2 and 6.1 ± 3.1 points, respectively; and mean PA of 4.91 ± 1.36°. An association was observed between females and PA <5.1° (P = .035), which was the cutoff point determined from the receiver operating characteristic curve. PA was correlated with APACHE II score (r = -0.241; P = .02). This correlation became moderate only when patients without sepsis were considered (r = -0.506; P < .001).
  
  
  CONCLUSIONS
  PA seems to be a good prognostic marker for patients without sepsis. The weak correlation between PA and APACHE II score and the lack of association with other clinical outcomes are limitations for interpreting the prognostic value of PA in the entire study sample.
authors.affiliation: Multiprofessional Integrated Residency Program in Health, with emphasis on Critical Adults, Hospital de Clínicas de Porto Alegre, Brazil Food and Nutrition Research Center, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Brazil.
authors.forename: Taís Kereski
authors.initials: TK
authors.lastname: da Silva
authors.affiliation: Multiprofessional Integrated Residency Program in Health, with emphasis on Critical Adults, Hospital de Clínicas de Porto Alegre, Brazil Food and Nutrition Research Center, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Brazil.
authors.forename: Marina Carvalho
authors.initials: MC
authors.lastname: Berbigier
authors.affiliation: Food and Nutrition Research Center, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Brazil Nutrition and Dietetics Service, Hospital de Clínicas de Porto Alegre, Brazil.
authors.forename: Bibiana de Almeida
authors.initials: Bde A
authors.lastname: Rubin
authors.affiliation: Intensive Medicine Service, Hospital de Clínicas de Porto Alegre, Brazil.
authors.forename: Rafael Barberena
authors.initials: RB
authors.lastname: Moraes
authors.affiliation: Food and Nutrition Research Center, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Brazil Intensive Medicine Department, School of Medicine, Universidade Federal do Rio Grande do Sul, Brazil.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Corrêa Souza
authors.affiliation: Food and Nutrition Research Center, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Brazil Health Unit, Universidade do Extremo Sul Catarinense, Criciúma, Brazil atputp@gmail.com.
authors.forename: Ingrid Dalira
authors.initials: ID
authors.lastname: Schweigert Perry
mesh_terms: D018806:APACHE; D000368:Aged; D015415:Biomarkers / Q000032:analysis*; D001823:Body Composition; D015331:Cohort Studies; D016638:Critical Illness / Q000401:mortality*; D017097:Electric Impedance; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D063305:Organ Dysfunction Scores; D010992:Plethysmography, Impedance / Q000706:statistics & numerical data*; D011379:Prognosis; D012307:Risk Factors; D012737:Sex Factors
chemical_list: D015415:Biomarkers
keywords: bioeletrictrical impedance analysis; body composition; critical illness; phase angle