title: Potassium abnormalities in a pediatric intensive care unit: frequency and severity.
abstract: BACKGROUND
  Potassium abnormalities are common in critically ill patients. We describe the spectrum of potassium abnormalities in our tertiary-level pediatric intensive care unit (PICU).
  
  
  METHODS
  Retrospective observational cohort of all the patients admitted to a single-center tertiary PICU over a 1-year period. Medical records and laboratory results were obtained through a central electronic data repository.
  
  
  RESULTS
  A total of 512 patients had a potassium measurement. Of a total of 4484 potassium measurements, one-third had abnormal values. Hypokalemia affected 40% of the admissions. Mild hypokalemia (3-3.4 mmol/L) affected 24% of the admissions. Moderate or severe hypokalemia (K <3.0 mmol/L) affected 16% of the admissions. Hyperkalemia affected 29% of the admissions. Mild hyperkalemia (5.1-6.0 mmol/L) affected 17% of the admissions. Moderate or severe hyperkalemia (>6.0 mmol/L) affected 12%. Hemolysis affected 2% of all the samples and 24% of hyperkalemic values. On univariate analysis, severity of hypokalemia was associated with mortality (odds ratio 2.2, P = .003).
  
  
  CONCLUSIONS
  Mild potassium abnormalities are common in the PICU. Repeating hemolyzed hyperkalemic samples may be beneficial. Guidance in monitoring frequencies of potassium abnormalities in pediatric critical care is needed.
authors.affiliation: Division of Pediatric Critical Care Medicine, Massachusetts General Hospital, Boston, MA, USA.
authors.forename: Brian M
authors.initials: BM
authors.lastname: Cummings
authors.affiliation: Massachusetts General Hospital Biostatistics Center, Boston, MA, USA.
authors.forename: Eric A
authors.initials: EA
authors.lastname: Macklin
authors.affiliation: Division of Pediatric Critical Care Medicine, Massachusetts General Hospital, Boston, MA, USA.
authors.forename: Phoebe H
authors.initials: PH
authors.lastname: Yager
authors.affiliation: Division of Pediatrics Nephrology, Yawkey Center for Outpatient Care (MGH), Boston, MA, USA.
authors.forename: Amita
authors.initials: A
authors.lastname: Sharma
authors.affiliation: Division of Pediatric Critical Care Medicine, Massachusetts General Hospital, Boston, MA, USA nnoviski@partners.org.
authors.forename: Natan
authors.initials: N
authors.lastname: Noviski
mesh_terms: D001900:Boston / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D016638:Critical Illness; D005260:Female; D006801:Humans; D006947:Hyperkalemia / Q000453:epidemiology*; D007008:Hypokalemia / Q000453:epidemiology*; D007223:Infant; D015278:Intensive Care Units, Pediatric; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D012189:Retrospective Studies; D012720:Severity of Illness Index
keywords: hemolysis; hyperkalemia; hypokalemia; intensive care units; pediatric