Intensive Care Medicine

, Volume 36, Issue 2, pp 304–311 | Cite as

Incidence and prognosis of dysnatremias present on ICU admission

  • Georg-Christian FunkEmail author
  • Gregor LindnerEmail author
  • Wilfred Druml
  • Barbara Metnitz
  • Christoph Schwarz
  • Peter Bauer
  • Philipp G. H. Metnitz



Dysnatremias are common in patients admitted to the intensive care unit (ICU). Whether the presence of disorders of sodium balance on ICU admission is independently associated with excess mortality is unknown. We hypothesized that dysnatremias at the time of ICU admission are independent risk factors for increased mortality in critically ill patients.


We conducted a retrospective study in 77 medical, surgical, and mixed ICUs in Austria, with a database of 151,486 adults admitted consecutively over a period of 10 years (1998–2007).


Most patients (114,170, 75.4%) had normal sodium levels (135 ≤ Na ≤ 145 mmol/L) on ICU admission. The frequencies of borderline (130 ≤ Na < 135 mmol/L), mild (125 ≤ Na < 130 mmol/L), and severe hyponatremia (Na < 125 mmol/L) were 13.8%, 2.7%, and 1.2%, respectively. The frequencies of borderline (145 < Na ≤ 150 mmol/L), mild (150 < Na ≤ 155 mmol/L), and severe hypernatremia (Na > 155 mmol/L) were 5.1%, 1.2%, and 0.6%, respectively. All types and grades of dysnatremia were associated with increased raw and risk-adjusted hospital mortality ratios. Multiple logistic regression analysis showed an independent mortality risk rising with increasing severity of both hyponatremia and hypernatremia. Odds ratios and 95% confidence interval (CI) for borderline, mild, and severe hyponatremia were 1.32 (1.25–1.39), 1.89 (1.71–2.09), and 1.81 (1.56–2.10), respectively. Odds ratios and 95% CI for borderline, mild, and severe hypernatremia were 1.48 (1.36–1.61), 2.32 (1.98–2.73), and 3.64 (2.88–4.61), respectively.


Our results suggest that both hypo- and hypernatremia present on admission to the ICU are independent risk factors for poor prognosis.


Hyponatremia Hypernatremia Sodium Outcome Epidemiology 



We thank the members of the ASDI study group and the respective study coordinators in each intensive care unit:

Hubert Artmann, Kardinal Schwarzenberg’sches Krankenhaus, Schwarzach/Pongau; Andreas Bacher, AKH Wien Universitätskliniken, Wien; Thomas Bauer, LK Krems; Florin-Voicu Botha, Landes-Nervenklinik Linz Wagner-Jauregg, Linz; Georg Dezsenyi, LK Waldviertel Horn; Kurt Dörre, LK Waldviertel Waidhofen a.d. Thaya; Günther Edelmann, KA Rudolfstiftung, Wien; Ingrid Eder, UKH Linz; Felix Ernst, LK Weinviertel Mistelbach; Ulrike Fasching, A.ö. LKH Steyr; Fritz Firlinger, A.ö. KH der Barmherzigen Brüder Linz; Herbert Fresacher, KH Hietzing m.Neurolog.Zentrum Rosenhügel, Wien; Norbert Fritsch, A.ö. LKH Enns; Alexander Geppert, Wilhelminenspital der Stadt Wien; Peter Grausenburger, LK Krems; Burkhart Gustorff, Wilhelminenspital der Stadt Wien; Georg Halvax, A.ö. KH der Barmherzigen Brüder St.Veit; Bernhard Hartenthaler, A.ö. LKH Vöcklabruck; Gottfried Heinz, AKH Wien Universitätskliniken, Wien; Ursula Hiermanseder, A.ö. LKH Schärding; Michael Hiesmayr, AKH Wien Universitätskliniken, Wien; Michael Hill, A.ö. KH der Barmherzigen Brüder Eisenstadt; Martin Holzleithner, A.ö. LKH Gmunden; Kurt Hudabiunigg, UKH Graz; Wolfgang Hufnagl, KH der Barmherzigen Brüder Salzburg; Thomas Janous, LK Waldviertel Zwettl; Sylvester Klaunzer, UKH Salzburg; Walter Klimscha, Donauspital SMZ Ost, Wien; Ilse Köfler, A.ö. LKH Bad Ischl; Gerhard Koinig, LK Thermenregion Neunkirchen; Claus Krenn, AKH Wien; Universitätskliniken, Wien; Dietmar Krucher, LK St. Pölten; Karl Lampl, LK Voralpen Lilienfeld; Peter Liebhart, LK Waldviertel Horn; Dieter Linemayr, LK Mödling; Siegfried Lister, Hartmannspital, Wien; Gottfried Locker, AKH Wien Universitätskliniken, Wien; Christian Madl, AKH Wien Universitätskliniken, Wien; Heinz Malle, UKH Klagenfurt; Walter Mauritz, UKH Lorenz Böhler, Wien; Alfred Meguscher, KH Hietzing m.Neurolog.Zentrum Rosenhügel, Wien; Gerfried Naderer, LK Weinviertel Hollabrunn; Petrus Novotny, KH Hietzing m.Neurolog.Zentrum Rosenhügel, Wien; Brigitte Pichler, LK Weinviertel Mistelbach; Walter Plöchl, AKH Wien Universitätskliniken, Wien; Georg Pötzl, Neurologisches Krankenhaus Rosenhügel, Wien; Thomas Publig, KH Hietzing m.Neurolog.Zentrum Rosenhügel, Wien; Richard Rabitsch, A.ö. LKH Rohrbach; Johanna Rech, A.ö. KH der Barmherzigen Brüder Linz; Wolfgang Regal, Kaiser-Franz-Josef-Spital Wien; Michael Rosner, Kaiser-Franz-Josef-Spital Wien; Günter Sagmüller, UKH Meidling; Stefan Schatzl, KH Hietzing m.Neurolog.Zentrum Rosenhügel, Wien; Ingrid Schindler, Sozialmedizinisches Zentrum Floridsdorf, Wien; Oswald Schuberth, A.ö. LKH Kirchdorf; Reinhard Schuster, Donauspital SMZ Ost, Wien; Franz Schwameis, LK Thermenregion Baden; Christian Spiess, AKH Wien Universitätskliniken, Wien; Gabriele Sprinzl, LK Donauregion Tulln; Franz Sterrer, Aö LKH Vöcklabruck; Franz Tichelmann, SMZ Baumgartner Höhe, Otto-Wagner-Spital, Wien; Helmut Trimmel, LK Wr. Neustadt; Roman Ullrich, AKH Wien Universitätskliniken, Wien; Andreas Valentin, KA Rudolfstiftung, Wien; Herbert Vesely, Hanusch Krankenhaus, Wien; Ernst Weilguny, A.ö. LKH Freistadt; Christian Weinstabl, AKH Wien; Universitätskliniken, Wien; Franz Wimmer, Kardinal Schwarzenberg’sches Krankenhaus, Schwarzach/Pongau; Peter Zanon, Zentrales Krankenhaus Bozen; Michael Zeilinger, Sozialmedizinisches Zentrum Floridsdorf, Wien.

Conflicts of interest

The authors have no actual or potential conflicts of interest. There was no financial support for the realization of this study. The authors have full control of all primary data and agree to allow the journal to review their data if requested.

Supplementary material

134_2009_1692_MOESM1_ESM.doc (128 kb)
Supplementary material 1 (DOC 128 kb)


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Copyright information

© Copyright jointly hold by Springer and ESICM 2009

Authors and Affiliations

  • Georg-Christian Funk
    • 1
    Email author
  • Gregor Lindner
    • 2
    Email author
  • Wilfred Druml
    • 3
  • Barbara Metnitz
    • 4
  • Christoph Schwarz
    • 5
  • Peter Bauer
    • 4
  • Philipp G. H. Metnitz
    • 2
  1. 1.Department of Respiratory and Critical Care MedicineOtto Wagner SpitalViennaAustria
  2. 2.Department of Anesthesiology and General Intensive Care MedicineMedical University of ViennaViennaAustria
  3. 3.Department of Nephrology and DialysisMedical University of ViennaViennaAustria
  4. 4.Department of Medical StatisticsMedical University of ViennaViennaAustria
  5. 5.Third Medical DepartmentKrankenhaus der ElisabethinenLinzAustria

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