Intervention: After informed consent, all routinely determined baseline data will be assessed including medical history, clinical items (i.e. neurological status, volume status, pulse rate, blood pressure, weight) and laboratory items (i.e. urine / serum osmolality, electrolytes, among others). All patients will have a follow-up with clinical and laboratory assessment until the day of discharge. After 3 months, they will be followed-up by a structured telephone interview to assess outcome (mortality, morbidity, as assessed by the ranking scale and Barthel index). Copeptin will be assessed in a batch analysis upon completion of the plasma asseveration.