Sterns Richard H, Silver Stephen M
University of Rochester School of Medicine and Dentistry, Nephrology Division, Rochester General Hospital, Rochester, New York, USA.
Curr Opin Nephrol Hypertens. 2016 Mar;25(2):114-9. doi: 10.1097/MNH.0000000000000200.
Hyponatremia causes significant morbidity, mortality, and disability. This review considers the literature of the past 18 months to improve understanding of these complications and to identify therapeutic strategies to prevent them.
Acute hyponatremia causes serious brain swelling that can lead to permanent disability or death. A 4-6 mEq/l increase in serum sodium is sufficient to reverse impending herniation. Brain swelling is minimal in chronic hyponatremia, and to avoid osmotic demyelination, correction should not exceed 8 mEq/l/day. In high-risk patients, correction should not exceed 4-6 mEq/l/day. Inadvertent overcorrection of hyponatremia is common and preventable by controlling unwanted urinary water losses with desmopressin. Even mild chronic hyponatremia is associated with increased mortality, attention deficit, gait instability, osteoporosis, and fractures, but it is not known if the correction of mild hyponatremia improves outcomes.
Controlled trials are needed to identify affordable treatments for hyponatremia that reduce the need for hospitalization, decrease hospital length of stay, and decrease morbidity. Such trials could also help answer the question of whether hyponatremia causes excess mortality or whether it is simply a marker for severe, lethal, underlying disease.
低钠血症会导致显著的发病率、死亡率和残疾。本综述探讨过去18个月的文献，以增进对这些并发症的理解，并确定预防它们的治疗策略。
急性低钠血症会导致严重的脑水肿，可导致永久性残疾或死亡。血清钠升高4 - 6mEq/l足以逆转即将发生的脑疝。慢性低钠血症时脑水肿轻微，为避免渗透性脱髓鞘，血清钠纠正幅度不应超过8mEq/l/天。对于高危患者，纠正幅度不应超过4 - 6mEq/l/天。低钠血症的意外过度纠正很常见，可通过使用去氨加压素控制不必要的尿水丢失来预防。即使是轻度慢性低钠血症也与死亡率增加、注意力缺陷、步态不稳、骨质疏松和骨折有关，但尚不清楚纠正轻度低钠血症是否能改善预后。
需要进行对照试验，以确定可负担得起的低钠血症治疗方法，减少住院需求、缩短住院时间并降低发病率。此类试验还可帮助回答低钠血症是导致额外死亡率，还是仅仅是严重致命基础疾病的一个指标这一问题。
