Factors predicting postoperative hyponatremia and efficacy of hyponatremia management strategies after more than 1000 pituitary operations

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Syndrome of inappropriate antidiuretic hormone secretion–induced hyponatremia is a common morbidity after pituitary surgery that can be profoundly symptomatic and cause costly readmissions. The authors calculated the frequency of postoperative hyponatremia after 1045 consecutive operations and determined the efficacy of interventions correcting hyponatremia.


The authors performed a retrospective review of 1045 consecutive pituitary surgeries in the first 946 patients treated since forming a dedicated pituitary center 5 years ago. Patients underwent preoperative and daily inpatient sodium checks, with outpatient checks as needed.


Thirty-two patients presented with hyponatremia; 41% of these patients were symptomatic. Postoperative hyponatremia occurred after 165 operations (16%) a mean of 4 days after surgery (range 0–28 days); 19% of operations leading to postoperative hyponatremia were associated with postoperative symptoms (38% involved dizziness and 29% involved nausea/vomiting) and 15% involved readmission for a mean of 5 days (range 1–20 days). In a multivariate analysis including lesion size, age, sex, number of prior pituitary surgeries, surgical approach, pathology, lesion location, and preoperative hypopituitarism, only preoperative hypopituitarism predicted postoperative hyponatremia (p = 0.006). Of patients with preoperative hyponatremia, 59% underwent medical correction preoperatively and 56% had persistent postoperative hyponatremia. The mean correction rates were 0.4 mEq/L/hr (no treatment; n = 112), 0.5 mEq/L/hr (free water restriction; n = 24), 0.7 mEq/L/hr (salt tablets; n = 14), 0.3 mEq/L/hr (3% saline; n = 20), 0.7 mEq/L/hr (intravenous vasopressin receptor antagonist Vaprisol; n = 22), and 1.2 mEq/L/hr (oral vasopressin receptor antagonist tolvaptan; n = 9) (p = 0.002, ANOVA). While some patients received more than 1 treatment, correction rates were only recorded when a treatment was given alone.


After 1045 pituitary operations, postoperative hyponatremia was associated exclusively with preoperative hypopituitarism and was most efficiently managed with oral tolvaptan, with several interventions insignificantly different from no treatment. Promptly identifying hyponatremia in high-risk patients and management with agents like tolvaptan can improve safety and decrease readmission. For readmitted patients with severely symptomatic hyponatremia, the intravenous vasopressin receptor antagonist Vaprisol is another treatment option.

Abbreviations used in this paper:ADH = antidiuretic hormone; SIADH = syndrome of inappropriate ADH secretion.
Article Information

Contributor Notes

Address correspondence to: Manish K. Aghi, M.D., Ph.D., Department of Neurosurgery, University of California at San Francisco, 505 Parnassus Ave., Room M779, San Francisco, CA 94143-0112. email: AghiM@neurosurg.ucsf.edu.Please include this information when citing this paper: published online August 23, 2013; DOI: 10.3171/2013.7.JNS13273.

© AANS, except where prohibited by US copyright law.

  • 1

    Dasta JFChiong JRChristian RLin J: Evaluation of costs associated with tolvaptan-mediated hospital length of stay reduction among US patients with the syndrome of inappropriate antidiuretic hormone secretion, based on SALT-1 and SALT-2 trials. Hosp Pract (1995) 40:7142012

    • Search Google Scholar
    • Export Citation
  • 2

    Guerrero RPumar ASoto APomares MAPalma SMangas MA: Early hyponatraemia after pituitary surgery: cerebral salt-wasting syndrome. Eur J Endocrinol 156:6116162007

    • Search Google Scholar
    • Export Citation
  • 3

    Kelly DFLaws ER JrFossett D: Delayed hyponatremia after transsphenoidal surgery for pituitary adenoma. Report of nine cases. J Neurosurg 83:3633671995

    • Search Google Scholar
    • Export Citation
  • 4

    Kinoshita YTominaga AArita KSugiyama KHanaya RHama S: Post-operative hyponatremia in patients with pituitary adenoma: post-operative management with a uniform treatment protocol. Endocr J 58:3733792011

    • Search Google Scholar
    • Export Citation
  • 5

    Kristof RARother MNeuloh GKlingmüller D: Incidence, clinical manifestations, and course of water and electrolyte metabolism disturbances following transsphenoidal pituitary adenoma surgery: a prospective observational study. Clinical article. J Neurosurg 111:5555622009

    • Search Google Scholar
    • Export Citation
  • 6

    Lee JICho WHChoi BKCha SHSong GSChoi CH: Delayed hyponatremia following transsphenoidal surgery for pituitary adenoma. Neurol Med Chir (Tokyo) 48:4894942008

    • Search Google Scholar
    • Export Citation
  • 7

    Nathan BR: Cerebral correlates of hyponatremia. Neurocrit Care 6:72782007

  • 8

    Olson BRGumowski JRubino DOldfield EH: Pathophysiology of hyponatremia after transsphenoidal pituitary surgery. J Neurosurg 87:4995071997

    • Search Google Scholar
    • Export Citation
  • 9

    Potts MBDeGiacomo AFDeragopian LBlevins LS Jr: Use of intravenous conivaptan in neurosurgical patients with hyponatremia from syndrome of inappropriate antidiuretic hormone secretion. Neurosurgery 69:2682732011

    • Search Google Scholar
    • Export Citation
  • 10

    Schrier RWSharma SShchekochikhin D: Hyponatraemia: more than just a marker of disease severity?. Nat Rev Nephrol 9:37502013

  • 11

    Staiger RDSarnthein JWiesli PSchmid CBernays RL: Prognostic factors for impaired plasma sodium homeostasis after transsphenoidal surgery. Br J Neurosurg 27:63682013

    • Search Google Scholar
    • Export Citation
  • 12

    Sterns RHix J: Hyponatremia: vasopressin antagonists in hyponatremia: more data needed. Nat Rev Nephrol 7:1321332011

  • 13

    Sun GEPantalone KMHatipoglu B: Hypothyroidism as a cause of hyponatremia: fact or fiction?. Endocr Pract 18:8948972012

  • 14

    Taylor SLTyrrell JBWilson CB: Delayed onset of hyponatremia after transsphenoidal surgery for pituitary adenomas. Neurosurgery 37:6496541995

    • Search Google Scholar
    • Export Citation
  • 15

    Zada GLiu CYFishback DSinger PAWeiss MH: Recognition and management of delayed hyponatremia following transsphenoidal pituitary surgery. J Neurosurg 106:66712007

    • Search Google Scholar
    • Export Citation


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