SIADH-related hyponatremia in hospital day care units: clinical experience and management with tolvaptan

Hyponatremia (Na ˂ 135 mmol/l) is the most frequent electrolyte disorder in clinical practice, and the syndrome of inappropriate antidiuretic hormone secretion (SIADH) is the commonest cause of hyponatremia in cancer patients. Correcting hyponatremia in these patients can reduce morbidity and mortality, increase the response to anti-cancer agents, and help reduce hospital length of stay and costs. Tolvaptan is an oral medication used to treat SIADH-related hyponatremia patients that needs to be initiated at hospital so patients can have their serum sodium monitored. If tolvaptan could be initiated in hospital day care units (DCUs), performing the same tests, hospitalization could be avoided, quality of life improved, and costs reduced. This is the first publication where a panel of oncologists are sharing their experience and making some recommendations with the use of tolvaptan to treat SIADH-related hyponatremia in DCU after collecting and examining 35 clinical cases with these type of patients. The conclusion from this retrospective observational analysis is that the use of tolvaptan in DCU is safe and effective in the therapeutic management of SIADH-related hyponatremia.