Research Unit on Hydromineral Metabolism, Department of General Internal Medicine, University Erasme Hospital, ULB, Route de Lennik 808, Brussels, B-1070, Belgium.
Crit Care. 2010;14(5):R184. doi: 10.1186/cc9292. Epub 2010 Oct 14.
Hyponatremia in the intensive care unit (ICU) is most commonly related to inappropriate secretion of antidiuretic hormone (SIADH). Fluid restriction is difficult to apply in these patients. We wanted to report the treatment of hyponatremia with urea in these patients.
Two groups of patients are reported. The first one is represented by a retrospective study of 50 consecutive patients with mild hyponatremia treated with urea. The second group is presented by a series of 35 consecutive patients with severe hyponatremia acquired outside the hospital (≤ 115 mEq/L) who where treated by isotonic saline and urea (0.5 to 1 g/kg/day), administered usually by gastric tube.
In the first group with mild hyponatremia (128 ± 4 mEq/L) the serum sodium (SNa) increased to a mean value of 135 ± 4 mEq/L (P < 0.001) after two days of urea therapy (46 ± 25 g/day), despite a large fluid intake (> 2 L/day). The mean duration of urea therapy was six days (from 2 to 42 days). Six patients developed hyponatremia again once the urea was stopped, which necessitated its reintroduction. Six patients developed hypernatremia (maximum value 155 mEq/L). In the second group, SNa increased from 111 ± 3 mEq/L to 122 ± 4 mEq/L in one day (P < 0.001). All the patients with neurological symptoms made a rapid recovery. No side effects were observed.
These data show that urea is a simple and inexpensive therapy to treat euvolemic hyponatremia in the ICU.
重症监护病房（ICU）中的低钠血症最常与抗利尿激素分泌不当（SIADH）有关。在这些患者中，限制液体摄入是困难的。我们报告了在这些患者中使用尿素治疗低钠血症的情况。
报告了两组患者。第一组是对 50 例连续轻度低钠血症患者使用尿素治疗的回顾性研究。第二组是由 35 例连续在院外发生的严重低钠血症患者组成的系列研究（≤115 mEq/L），他们接受等渗盐水和尿素（0.5 至 1 g/kg/天）治疗，通常通过胃管给药。
在轻度低钠血症（128 ± 4 mEq/L）的第一组中，尽管大量液体摄入（>2 L/天），但在接受尿素治疗两天后（46 ± 25 g/天），血清钠（SNa）升高至 135 ± 4 mEq/L 的平均值（P < 0.001）。尿素治疗的平均持续时间为六天（2 至 42 天）。六名患者在停止尿素治疗后再次出现低钠血症，需要重新引入。六名患者出现高钠血症（最高值 155 mEq/L）。在第二组中，SNa 在一天内从 111 ± 3 mEq/L 增加到 122 ± 4 mEq/L（P < 0.001）。所有有神经症状的患者均迅速恢复。未观察到不良反应。
这些数据表明，尿素是治疗 ICU 中容量正常性低钠血症的一种简单且廉价的治疗方法。
