Trying to wrap my brain around this one...

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I have done quite a bit of reading on this topic, and I still can't quite grasp what this situation was so will present it here in the hope of better understanding it.

Patient with an extensive psych hx presents with hyponatremia and urinary retention. Foley is placed and immediately drains >1800mL of urine. Foley clamped long enough to drain the bag and when unclamped another 2000mL of urine drains. Bag is emptied and in the time it takes for pt to go to the floor (probably around 30 minutes) another >1700mL drains. Over the next 2-3 hours, around 3000mL drains again. Dr. orders foley clamped, foley is clamped, and after 3 hours (time frame dr wanted it clamped) 200mL had literally pushed through the clamped tubing and another >2000mL drains once unclamped.

Urine specific gravity was ~1.005, urine osmolality was low end of normal, urine Na and other levels were wnl. Urine osmolarity was also wnl. Serum Na was ~120.

What do do you think was happening? My first thought went to diabetes insipidus, perhaps as a side effect of psych meds (lithium was one med, which I read a rare side effect can be DI, but there were probably around a half a dozen psych meds). There didn't seem to be an increased thirst, and fluids were running at 75mL/hr.

I just am really curious about this. I have never seen such a urine output before :eek: Any ideas?

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Specializes in ICU, LTACH, Internal Medicine.

If things looked like you described, it is poliuria with decreased concentration. Causes could be many, from insipidus (yes, lithium causes similar condition) to psychogenic polydipsia (common; disinhibition of thirst center, patients drink like horses, dangerous due to electrolytes alterations ) with a few things in between, which may or may not have anything in common with psych history or meds.

I hope anybody realized that such patient must be on strict I&O, tele and electrolyte monitoring. Also, it was absolutely not necessary to clamp Foley once it was found that urinary output is so high. At the least, it was less than pleasant for the poor guy.

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Thanks KatieMI...pt was on tele and monitoring both serum and urine lytes. Nearly everyone on our floor is on strict I/Os (pretty rare not to be for us).

I couldn't understand the reason behind the clamping (I thought there was no EBP for foley clamping), and all I could imagine was all that urine backing up and up and up :nailbiting: I just was so interested in this since it was a new one for me. I almost (almost ;)) wished I had been scheduled the following day to find out what was going on.

Thanks again for the reply!

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As KatieMI said, it's probably psychogenic polydipsia. DI would cause hypernatremia due to dehydration (lack of ADH causes loss of free water while Na level stays the same, increasing the total concentration). This pt needs to be on fluid restriction and sometimes salt tablet to bring the Na level up, and frequent Na monitoring.

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Specializes in School Nursing, Hospice,Med-Surg.

I had a psych pt on med-surg with water intoxication many years ago. He required more than just strict I/O's. We had to first remove the faucet & shower handles to keep him from drinking water when we weren't watching. Then we caught him drinking from the toilet so we had to call custodial to drain the toilet. :sigh:

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As KatieMI said, it's probably psychogenic polydipsia. DI would cause hypernatremia due to dehydration (lack of ADH causes loss of free water while Na level stays the same, increasing the total concentration). This pt needs to be on fluid restriction and sometimes salt tablet to bring the Na level up, and frequent Na monitoring.

This was why I didn't understand the situation because I thought DI would present with hypernatremia like you pointed out. Unless the pt drank like crazy prior to admission, there was no polydipsia. Pt had oral intake of ~200mL for the entire period I described.

Thank you for the reply! :)

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I had a psych pt on med-surg with water intoxication many years ago. He required more than just strict I/O's. We had to first remove the faucet & shower handles to keep him from drinking water when we weren't watching. Then we caught him drinking from the toilet so we had to call custodial to drain the toilet. :sigh:

Wowza! :eek:

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Specializes in ICU, LTACH, Internal Medicine.
As KatieMI said, it's probably psychogenic polydipsia. DI would cause hypernatremia due to dehydration (lack of ADH causes loss of free water while Na level stays the same, increasing the total concentration). This pt needs to be on fluid restriction and sometimes salt tablet to bring the Na level up, and frequent Na monitoring.

DI presents with hypernatremia ONLY when access to water is restricted. If patient is allowed to drink, sodium concentration will, eventually, decrease due to losses.

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