Kelly D F, Laws E R, Fossett D
Department of Neurosurgery, University of California Los Angeles Medical Center, Torrance, USA.
J Neurosurg. 1995 Aug;83(2):363-7. doi: 10.3171/jns.1995.83.2.0363.
Hyponatremia, usually attributed to the syndrome of inappropriate secretion of antidiuretic hormone, typically occurs in a delayed fashion following transsphenoidal removal of a pituitary adenoma. In a series of 99 consecutive patients who underwent transsphenoidal surgery for pituitary adenoma, nine patients developed delayed hyponatremia, seven of whom were symptomatic. Of these seven patients, four had been discharged from the hospital and required readmission on postoperative Day 7 to 9. In the nine patients who developed hyponatremia, on the average, serum sodium levels began to fall on Day 4 and reached a nadir on Day 7 (mean serum sodium nadir 123 mmol/L). The development of delayed hyponatremia was associated with the presence of a macroadenoma in eight of the nine patients. Seven of the nine patients had serum sodium levels less than 130 mmol/L and required treatment. One patient was treated with fluid restriction alone and six were treated with both fluid restriction and intravenous urea therapy. Twenty-four and 48 hours after urea administration, serum sodium levels rose by an average of 6 and 10 mmol/L, respectively, and at discharge, levels averaged 136 mmol/L. Intravenous administration of urea provides a rapid yet safe means of correcting symptomatic hyponatremia when fluid restriction alone is inadequate. In this article, the authors discuss the pathogenesis of delayed hyponatremia.
低钠血症通常归因于抗利尿激素分泌不当综合征，典型地发生在经蝶窦切除垂体腺瘤后的延迟期。在一组连续99例行垂体腺瘤经蝶窦手术的患者中，9例发生延迟性低钠血症，其中7例出现症状。在这7例患者中，4例已出院，术后第7至9天需要再次入院。在发生低钠血症的9例患者中，血清钠水平平均在术后第4天开始下降，第7天降至最低点（血清钠最低值平均为123 mmol/L）。9例患者中有8例延迟性低钠血症的发生与大腺瘤有关。9例患者中有7例血清钠水平低于130 mmol/L，需要治疗。1例患者仅采用限液治疗，6例患者采用限液和静脉注射尿素治疗。静脉注射尿素后24小时和48小时，血清钠水平分别平均升高6 mmol/L和10 mmol/L，出院时平均水平为136 mmol/L。当仅靠限液不足以纠正症状性低钠血症时，静脉注射尿素提供了一种快速且安全的方法。在本文中，作者讨论了延迟性低钠血症的发病机制。
