title: Incidence, Etiology and Outcomes of Hyponatremia after Transsphenoidal Surgery: Experience with 344 Consecutive Patients at a Single Tertiary Center.
abstract: Hyponatremia is often seen after transsphenoidal surgery and is a source of considerable economic burden and patient-related morbidity and mortality. We performed a retrospective review of 344 patients who underwent transsphenoidal surgery at our institution between 2006 and 2012. Postoperative hyponatremia was seen in 18.0% of patients at a mean of 3.9 days postoperatively. Hyponatremia was most commonly mild (51.6%) and clinically asymptomatic (93.8%). SIADH was the primary cause of hyponatremia in the majority of cases (n = 44, 71.0%), followed by cerebral salt wasting (n = 15, 24.2%) and desmopressin over-administration (n = 3, 4.8%). The incidence of postoperative hyponatremia was significantly higher in patients with cardiac, renal and/or thyroid disease (p = 0.0034, Objective Risk (OR) = 2.60) and in female patients (p = 0.011, OR = 2.18) or patients undergoing post-operative cerebrospinal fluid drainage (p = 0.0006). Treatment with hypertonic saline (OR = -2.4, p = 0.10) and sodium chloride tablets (OR = -1.57, p = 0.45) was associated with a non-significant trend toward faster resolution of hyponatremia. The use of fluid restriction and diuretics should be de-emphasized in the treatment of post-transsphenoidal hyponatremia, as they have not been shown to significantly alter the time-course to the restoration of sodium balance.
authors.affiliation: Department of Neurosurgery, Houston Methodist Neurological Institute and the Kenneth R, Peak Brain and Pituitary Tumor Treatment Center, 6560 Fannin St. Suite 944, Houston, TX 77030, USA.
authors.forename: Sean M
authors.initials: SM
authors.lastname: Barber
authors.affiliation: Department of Neurosurgery, Houston Methodist Neurological Institute and the Kenneth R, Peak Brain and Pituitary Tumor Treatment Center, 6560 Fannin St. Suite 944, Houston, TX 77030, USA.
authors.forename: Brandon D
authors.initials: BD
authors.lastname: Liebelt
authors.affiliation: Department of Neurosurgery, Houston Methodist Neurological Institute and the Kenneth R, Peak Brain and Pituitary Tumor Treatment Center, 6560 Fannin St. Suite 944, Houston, TX 77030, USA. dbaskin@houstonmethodist.org.
authors.forename: David S
authors.initials: DS
authors.lastname: Baskin
keywords: SIADH; cerebral salt wasting; hyponatremia; pituitary adenoma; transsphenoidal