The bioimpedance spectroscopy as useful tool for measuring the fluid excess and fluid management in severe polytrauma patients.

Although the fluid therapy plays a fundamental role in the management of polytrauma patients (PP), a tool which could determine it appropriately is still lacking. The aim of this study was to evaluate the application of a bioimpedance spectroscopy (BIS) for body fluids volume and distribution monitoring in these patients. This prospective, observational study was performed on 25 severe PP and 25 healthy subjects. The body fluids composition was repeatedly assessed using BIS between days 3 to 11 of intensive care unit stay while the impact of fluid intake and balance was evaluated. Fluid intake correlated significantly with fluid excess (FE) in edemas, and their values were significantly higher in comparison with the control group. FE was strongly associated with cumulative fluid balance (p<0.0001; r=0.719). Furthermore, this parameter was associated with the entire duration of mechanical ventilation (p=0.001, r=0.791) independently of injury severity score. In conclusion, BIS measured FE could be useful in PP who already achieved negative fluid balance in prevention the risk of repeated hypovolemia through inappropriate fluid restriction. What is more, measured FE has a certain prognostic value. Further studies are required to confirm BIS as a potential instrument for the improvement of PP outcome.