Abstract: PO1433
Urea as a Newer Therapy for Hyponatremia
Session Information
- Fluid, Electrolyte, and Acid-Base Disorders: Clinical - 1
October 22, 2020 | Location: On-Demand
Abstract Time: 10:00 AM - 12:00 PM
Category: Fluid, Electrolyte, and Acid-Base Disorders
- 902 Fluid, Electrolyte, and Acid-Base Disorders: Clinical
Authors
- Mutnuri, Sangeeta, Creighton University, Omaha, Nebraska, United States
- Srinivasan, Aswin, University of Houston, Houston, Texas, United States
- Safri, Shabbir, Montefiore Medical Center, Bronx, New York, United States
- Agraharkar, Mahendra L., UTMB, University of Texas Medical Branch at Galveston, Galveston, Texas, United States
Introduction
Hyponatremia is the most common electrolyte disorder observed in hospitalized patients and is associated with increased mortality, length of stay and readmission rates. Treatment includes fluid restriction, salt tablets, intravenous (IV) hypertonic saline and Antidiuretic Hormone (ADH) antagonists. Urea is a known therapy option for SIADH, but has been an infrequent choice.
Case Description
We present five cases of hyponatremia. The ages of the first four patients who had good response to urea were all older than 50 years. They included three SIADH patients and one hypervolemic hyponatremia. The hypervolemic patient had a reduced ejection fraction and had no improvement with diuresis and salt tablets and responded to urea. Of the other three, one required hypertonic saline and transition to urea, the other had been treated with tolvaptan and switched to urea due to cost concerns and the third patient had a component of low solute intake which responded well to urea. The fourth patient had SIADH secondary to malignancy and needed a combination of salt tablets and urea to achieve goal sodium. Addition of urea to salt tablets lowered the dose of salt tablets needed to maintain goal sodium. The last and youngest patient did not respond well to urea and needed tolvaptan to maintain sodium levels at goal.
Discussion
The treatment of hyponatremia is challenging as the correction has to be controlled to avoid osmotic demyelination syndrome from rapid fluid shifts. While hypertonic saline is a reliable treatment in hospitalized patients, it can prolong hospital stays. Tolvaptan helps with sodium correction, but is limited by its cost and liver toxicity. Urea increased serum sodium levels reliably in our older patients and reduced dose of salt tablets needed. In comparison to Tolvaptan, urea is a cost-effective alternative. Salt tablets are more affordable but cause volume overload. Hence, we think urea is a newer, well-tolerated and safer option in the treatment of hyponatremia either alone or in combination with other therapies.
Case Description
| Patient | Age/Sex | Admission Na+ (meq/L) | Discharge Na+ (mEq/L) and treatment | Duration of admission (days) | Urine Osmolality (mOsm/kg) | urine Na+ (mEq/L) |
| 1 | 61 yo Female | 118 | 135 Salt tablets/diuresis/tolvaptan Lastly urea with good response | 26 | 211 | 34 |
| 2 | 77 yo Male | 117 | 131 Hypertonic saline and tolvaptan Switched to urea due to cost | 13 | 427 | 27 |
| 3 | 70 yo Male | 123 | 128 0.9% NS and then urea | 5 | 561 | 49 |
| 4 | 59 yo Male | 127 | 129 0.9% NS and urea with salt tablets | 16 | 629 | 181 |
| 5 | 39 yo Male | 115 | 135 Hypertonic saline, urea with variable response Tolvaptan worked well | 14 | 735 | 53 |