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 IJCM  Vol.7 No.10 , October 2016
Defining the Cause of Post-Operative Hyponatremia in the Orthopedic Patient
Abstract: Background: Post-operative hyponatremia occurs after 30% of orthopedic surgeries, increasing morbidity, mortality and hospital length of stays and hospital costs. The cause of the hyponatremia can be varied, hard to diagnose and impact management. The goal of this study was to determine the causes of post-operative orthopedic hyponatremia and to evaluate the accuracy with which nephrologists and internists interpret the data. Methods: This was a retrospective chart review of patients >21 years old on the adult total joint service who developed postoperative hyponatremia. A hyponatremic order set was developed and patient fluid status was charted by the presence or absence of edema in non-surgical extremities. The patients were treated by their managing physicians. After one year, data on 51 patients were assembled and sent to three nephrologists and three internists to analyze and diagnose the etiology of the hyponatremia. Results: The most common causes of post-operative hyponatremia were hypovolemia (33.7%), the syndrome of inappropriate antidiuretic hormone, SIADH (32.4%), hypotonic fluid (8.2%), acute kidney injury (5.2%) and medications (5.9%). The interrater agreement, measured by kappa coefficient, was moderate (0.43; 95% CI 0.34, 0.53) for the nephrologists and fair (0.38; 95% CI 0.30, 0.46) for the internists. Conclusions: The majority of post-operative hyponatremia following total joint surgery in adults is from hypovolemia and SIADH. The treatment for these is very different: the first requires fluid resuscitation and the latter, free water restriction. Due to an interplay of peri-operative factors, the diagnosis can be difficult for both internists as well as nephrologists.
Cite this paper: Hennrikus, E. , Georgeson, A. , Leymeister, K. , Mucha, S. , McGillen, B. and Miller, R. (2016) Defining the Cause of Post-Operative Hyponatremia in the Orthopedic Patient. International Journal of Clinical Medicine, 7, 668-674. doi: 10.4236/ijcm.2016.710072.
References

[1]   Hennrikus, E., Ou, G., Kinney, B., Lehman, E., Grunfeld, R., Wieler, J., Damluji, A., Davis III, C. and Mets, B. (2015) Prevalence, Timing, Causes, and Outcomes of Hyponatremia in Hospitalized Orthopaedic Surgery Patients. The Journal of Bone & Joint Surgery (American), 97, 1824-1832.
http://dx.doi.org/10.2106/JBJS.O.00103

[2]   Waikar, S.S., Mount, D.B. and Curhan, G.C. (2009) Mortality after Hospitalization with Mild, Moderate, and Severe Hyponatremia. American Journal of Medicine, 122, 857-865.
http://dx.doi.org/10.1016/j.amjmed.2009.01.027

[3]   Callewart, C.C., Minchew, J.T., Kanim, L.E., Tsai, Y.C., Salehmoghaddam, S., Dawson, E.G. and Delamarter, R.B. (1994) Hyponatremia and Syndrome of Inappropriate Antidiuretic Hormone Secretion in Adult Spinal Surgery. Spine, 19, 1674-1679.
http://dx.doi.org/10.1097/00007632-199408000-00004

[4]   Fenske, W., Maier, S.K., Blechschmidt, A., et al. (2010) Utility and Limitations of the Traditional Diagnostic Approach to Hyponatremia: A Diagnostic Study. American Journal of Medicine, 123, 652-657.
http://dx.doi.org/10.1016/j.amjmed.2010.01.013

[5]   Spasovski, G., Vanholder, R., Allolio, B., Annane, D., Ball, S., Bichet, D., Decaux, G., Fenske, W., Hoorn, E., Ichai, C., Joannidis, M., Soupart, A., Zietse, R., Haller, M., Van der Veer, S., Van Biesen, W. and Nagler, E. (2014) Clinical Practice Guideline on Diagnosis and Treatment of Hyponatraemia. European Journal of Endocrinology, 107, G1-G47.
http://dx.doi.org/10.2478/bj-2014-0014

[6]   Park, S.J. and Shin, J.L. (2013) Inflammation and Hyponatremia: An Underrecognized Condition? Korean Journal of Pediatrics, 56, 519-522.
http://dx.doi.org/10.3345/kjp.2013.56.12.519

[7]   Robertson, G.L. (2001) Antidiuretic Hormone. Normal and Disordered Function. Endocrinology and Metabolism Clinics of North America, 30, 671-694.
http://dx.doi.org/10.1016/S0889-8529(05)70207-3

[8]   Chung, H.M., Kluge, R., Schrier, R.W. and Anderson, R.J. (1987) Clinical Assessment of Extrcellular Fluid Volume in Hyponatremia. American Journal of Medicine, 83, 905-908.
http://dx.doi.org/10.1016/0002-9343(87)90649-8

[9]   Milionis, H.F., Liamis, G.L. and Elisaf, M.S. (2002) The Hyponatremic Patient: A Systematic Approach to Laboratory Diagnosis. CMAJ, 166, 1056-1062.

[10]   Fenske, W., Stork, S. and Koschker, A.C. (2008) Value of Fractional Uric Acid Excretion in Differential Diagnosis of Hyponatremic Patients on Diuretics. The Journal of Clinical Endocrinology & Metabolism, 93, 2991-2997.
http://dx.doi.org/10.1210/jc.2008-0330

[11]   Hato, T. and Ng, R. (2010) Diagnostic Value of Urine Sodium Concentration in Hyponatremia due to Syndrome of Inappropriate Antidiuretic Hormone Secretion versus Hypovolemia. Hawaii Medical Journal, 69, 264-267.

[12]   Palmer, B.F. (2010) Diagnostic Approach and Management of Inpatient Hyponatremia. JHM, 5, S1-S7.
http://dx.doi.org/10.1002/jhm.702

 
 
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