title: Severe hyperkalaemia: demographics and outcome.
abstract: BACKGROUND
  Few studies have evaluated the prevalence of severe hyperkalaemia in unselected patient populations. We identified all episodes of severe hyperkalaemia occurring in 1 year, and described patient demographics, clinical response and outcome. We also assessed junior doctor knowledge of its causes and significance.
  
  
  METHODS
  A retrospective interrogation of the database of the regional biochemical laboratory identified all episodes of severe hyperkalaemia (K≥ 6.5 mmol/L) occurring in 2011. The understanding of trainee doctors of the importance, causes and treatment of severe hyperkalaemia was assessed by structured questionnaire.
  
  
  RESULTS
  Severe hyperkalaemia was recorded in 433 samples (365 patients) giving a prevalence of 0.11%. Thirty-six per cent of episodes occurred in patients under the care of a nephrologist, who were significantly younger than those not under the care of a nephrologist. In the nephrology cohort, 86% occurred in patients with chronic kidney disease (CKD), the majority of which had CKD Stage 5. In the non-nephrology cohort, only 65% occurred in the context of CKD, which was equally distributed between Stages 3 and 5 CKD. In both patient groups, roughly 50% of episodes occurred in association with acute kidney injury (AKI). Acute mortality (death within 48 h of documented severe hyperkalaemia) was higher in the non-nephrology compared with the nephrology cohort. Time to repeat serum potassium was influenced by the clinical setting with shorter time to repeat for acute care compared with ward settings. Assessment of trainee doctor's knowledge suggested significant deficiencies in relation to severe hyperkalaemia.
  
  
  CONCLUSIONS
  The prevalence of severe hyperkalaemia was low and occurred predominantly in the context of CKD and/or AKI. The majority of episodes occurred in patients not under the care of a nephrologist. Variability in time to repeat serum potassium levels suggested deficiencies in care, and assessment of trainee doctor's knowledge suggests the need for further educational initiatives to highlight its importance.
authors: Insititute of Nephrology , Cardiff University School of Medicine , Cardiff , UK.
authors: B M
authors: BM
authors: Phillips
authors: Insititute of Nephrology , Cardiff University School of Medicine , Cardiff , UK.
authors: S
authors: S
authors: Milner
authors: Department of Biochemistry and Immunology , Cardiff and Vale University Health Board, University Hospital of Wales , Cardiff , UK ; Department of Medical Biochemistry, School of Medicine , Alexandria University , Alexandria , Egypt.
authors: S
authors: S
authors: Zouwail
authors: Department of Nephrology and Transplantation , Cardiff and Vale University Health Board, University Hospital of Wales , Cardiff , UK.
authors: G
authors: G
authors: Roberts
authors: Insititute of Nephrology , Cardiff University School of Medicine , Cardiff , UK.
authors: M
authors: M
authors: Cowan
authors: Insititute of Nephrology , Cardiff University School of Medicine , Cardiff , UK.
authors: S G
authors: SG
authors: Riley
authors: Insititute of Nephrology , Cardiff University School of Medicine , Cardiff , UK.
authors: A O
authors: AO
authors: Phillips
keywords: AKI; CKD; hyperkalaemia; potassium