The multifactorial aetiology of ICU-acquired hypernatremia

Abstract

Intensive care patients are threatened in their wellbeing by the acute illness that brought them on the ICU. This acute illness and its accessory treatment also disturb a lot of physiologic processes in the body. One of these processes is sodium handling. Disturbance of this process may lead to an elevated serum sodium concentration. An elevated sodium concentration contributes in ICU-patients to worsening of prognosis. Until now the factors that contribute to an elevated sodium concentration are not fully unravelled. In this thesis studies are described that contribute to enhancement of knowledge about the development of ICU-acquired hypernatremia. Firstly, in these studies (again) comes clear that ICU-patients get administered high amounts of sodium by the fluids that are necessary to keep those patients alive. In healthy persons, however, excessive sodium intake does not lead to elevation of sodium concentration. Based on the results of our studies we conclude that renal function seems to be important in the development of ICU-acquired hypernatremia. In most critically ill patients renal function – temporarily – worsens (seriously). Kidneys with impaired function on the one hand fail in excretion of sufficient amounts of sodium. On the other hand they are not able to retain enough water to compensate for the elevated sodium levels. No sufficient solution for this problem is known yet. In future the knowledge that this thesis adds to the current literature hopefully contributes to the prevention and/or treatment of ICU-acquired hypernatremia.