title: Normal saline to dilute parenteral drugs and to keep catheters open is a major and preventable source of hypernatremia acquired in the intensive care unit.
abstract: OBJECTIVE
  We wanted to identify modifiable risk factors for intensive care unit (ICU)-acquired hypernatremia.
  
  
  METHODS
  We retrospectively studied sodium and fluid loads and balances up to 7 days prior to the development of hypernatremia (first serum sodium concentration, [Na+], >150 mmol/L; H) vs control (maximum [Na+] ≤150 mmol/L; N), in consecutive patients admitted into the ICU with a normal serum sodium (<145 mmol/L) and without cerebral disease, within a period of 8 months.
  
  
  RESULTS
  There were 57 H and 150 N patients. Severity of disease and organ failure was greater, and length of stay and mechanical ventilation in the ICU were longer in H (P<.001), with a mortality rate of 28% vs 16% in N (P=.002). Sodium input was higher in H than in N, particularly from 0.9% saline to dissolve drugs for infusion and to keep catheters open during the week prior to the first day of hypernatremia (P<.001). Fluid balances were positive and did not differ from N on most days in the presence of slightly higher plasma creatinine and more frequent administration of furosemide, at higher doses, in H than in N.
  
  
  CONCLUSIONS
  High sodium input by 0.9% saline used to dilute drugs and keep catheters open is a modifiable risk factor for ICU-acquired H. Dissolving drugs in dextrose 5% may partially prevent potentially harmful sodium overloading and H.
authors.affiliation: Department of Clinical Pharmacology and Pharmacy, VU University Medical Center, Amsterdam, The Netherlands. Electronic address: w.choo@vumc.nl.
authors.forename: Wai-Ping
authors.initials: WP
authors.lastname: Choo
authors.affiliation: Department of Intensive Care, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: A B Johan
authors.initials: AB
authors.lastname: Groeneveld
authors.affiliation: Department of Intensive care, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Ronald H
authors.initials: RH
authors.lastname: Driessen
authors.affiliation: Department of Clinical Pharmacology and Pharmacy, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Eleonora L
authors.initials: EL
authors.lastname: Swart
mesh_terms: D000328:Adult; D000368:Aged; D061807:Catheter Obstruction; D003404:Creatinine / Q000097:blood; D004339:Drug Compounding / Q000009:adverse effects / Q000379:methods; D005260:Female; D006801:Humans; D006955:Hypernatremia / Q000097:blood / Q000139:chemically induced* / Q000517:prevention & control; D007362:Intensive Care Units; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D012121:Respiration, Artificial / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012307:Risk Factors; D012964:Sodium / Q000097:blood; D012965:Sodium Chloride / Q000008:administration & dosage / Q000009:adverse effects*; D014882:Water-Electrolyte Balance / Q000502:physiology
chemical_list: D012965:Sodium Chloride; D012964:Sodium; D003404:Creatinine
keywords: Critically ill; Hypernatremia; Parenteral drugs; Risk factors; Sodium and fluid balance