Management of severe hyponatremia with SIAD

Ally Prebtani, MD, is an endocrinologist, internist, and professor of medicine at McMaster University. He has developed clinical practice guidelines as part of Diabetes Canada and Hypertension Canada. He is actively involved in teaching, advocacy work, clinical work, and research.

How to manage patients with acute signs and symptoms of syndrome of inappropriate antidiuresis (SIAD), including rapidly progressing hyponatremia?

Ally Prebtani, MD: I think you’re referring to severe hyponatremia with SIAD. The first thing is, of course, your ABCs: airway, breathing, circulation. Once you’ve stabilized the patient or while you’re stabilizing them, you want to know whether this is acute or chronic. It is probably acute if it’s severe and they’re sick, then you want to use 3% normal saline. You can bolus them and try to attain a sodium quickly, 4 to 6 mEq/L within the first 1 to 2 hours. And if they’re responding, maybe give them 1 or 2 more boluses within 15 minutes each. But the key thing is to make sure you monitor their sodium very, very carefully and frequently.

Once you get there and they’re still symptomatic, then you want to correct them more slowly if they’ve improved. Then, you want to correct them slowly over the next 1 to 2 days, but much, much slower than you would have done initially because you can run into complications if you don’t do it slowly. And at this time you always want to look for the reason why they have SIAD, such as lung conditions, medications, brain conditions, etc.