Prevalence and clinical demographics of cerebral salt wasting in patients with aneurysmal subarachnoid hemorrhage

Abstract

Hyponatremia is a frequent complication following subarachnoid hemorrhage (SAH), and is commonly attributed either to the syndrome of inappropriate antidiuretic hormone secretion (SIADH) or cerebral salt wasting syndrome (CSW). The object of this study is to elucidate the clinical demographics and sequelae of hyponatremia due to CSW in subjects with aneurysmal SAH. Retrospective chart review of patients >18 years with aneurysmal SAH admitted between January 2004 and July 2007 was performed. Subjects with moderate to severe hyponatremia (serum sodium <130 mmol l(-1)) were divided into groups consistent with CSW and SIADH based on urine output, fluid balance, natriuresis, and response to saline infusion. Clinical demographics were compared. Of 316 subjects identified, hyponatremia (serum sodium <135 mmol l(-1)) was detected in 187 (59.2%) subjects and moderate to severe hyponatremia in 48 (15.2%). Of the latter group, 35.4% were categorized with SIADH and 22.9% with CSW. Compared to eunatremic subjects, hyponatremia was associated with significantly longer hospital stay (15.7 +/- 1.9 vs. 9.6 +/- 1.1 days, p < 0.001). Subjects with CSW had similar mortality and duration of hospital stay vs. those with SIADH. Though less common than SIADH, CSW was detected in approximately 23% of patients with history of aneurysmal SAH and was not clearly associated with enhanced morbidity and mortality compared to subjects with SIADH. Further studies regarding the pathogenesis and management, along with the medical consequences, of CSW are important.

Neurosurgical Hyponatremia

“…Hyponatremia is far more common following SAH than it is after TBI [4,5,6] occurring in approximately 50% of patients. The etiology of hyponatremia following subarachnoid hemorrhage is diverse [2] and potential causes include SIADH, acute glucocorticoid deficiency, and CSWS, as well as the more general causes of hyponatremia outlined in Table 2.…”

“…Some previous retrospective studies [4,7] have failed to substantiate cerebral salt wasting as a cause for anything more than a minority of cases of hyponatremia following SAH, and strongly support SIAD as the predominant cause of hyponatremia. In contrast, the similarly-sized retrospective study of Kao et al ., found that only 35.4% of severe hyponatremia (<130 mmol/L) was considered to be due to SIADH, with a substantial proportion—22.9%—considered to be secondary to CSWS [5]. However, only those patients with plasma sodium <130 mmol/L (a minority of the overall number of cases of hyponatremia) were analyzed in detail.…”

“…It is especially frequent in patients suffering from neurosurgical insult or intervention. Around 15% to 20% of patients admitted for Traumatic Brain Injury (TBI) [1,2,3] and over 50% of patients admitted for Subarachnoid Hemorrhage (SAH) [4,5,6] develop hyponatremia. In patients admitted to neurosurgical units with intracranial tumors and hematomas and in patients undergoing pituitary surgery, hyponatremia occurs in between 10% and 20% of patients [7].…”

The rate of hyponatremia in neurosurgical patients (comparison between the data from the Burdenko Neurosurgical Instutite and the literature) and recommendations for the diagnosis and treatment

“…Так, у 15-20% пациентов с нейротравмой [18,19] и почти у половины больных с субарахноидальными кровоизлияниями [20,21] выявляется снижение уровня Na в крови. Как правило, при этих состояни-ях гипонатриемия наблюдается в течение 2-4 дней и связана с отеком мозга.…”

“…В ретроспективном исследовании L. Као и соавт. [20] при обследовании больных с уровнем Na менее 130 ммоль/л в 35% случаев причиной гипонатрие-мии служил SIAD, в 22,9% -CSW. Недостатком большинства ретроспективных исследований явля-лось отсутствие рутинного измерения динамики кортизола в крови.…”