RESUMO
Every year about 800,000 cases of intestinal infections end in lethal outcome due to dehydration. The different types of dehydration acquire differential approach to correction. Everywhere there is no application of routine detection of osmolarity of blood plasma under exicosis in children in view of absence of possibility of instrumental measurement. The search of techniques is needed to make it possible to indirectly detect types of dehydration in children hospitalized because of acute intestinal infection with purpose to apply rationale therapy of water-electrolyte disorders. The sampling of 32 patients with intestinal infections accompanied with signs of exicosis degree I-III was examined. The detection of osmolarity of blood was implemented by instrumental technique using gas analyzer ABL 800 Flex (Radiometer; Denmark) and five estimate techniques according to results of biochemical analysis of blood. The differences in precision of measurement of osmolarity of blood plasma by instrumental and estimate techniques were compared using Bland-Altman graphic technique. It is established that formula: 2x[Na+kp] + [glucosekp] (mmol/l) is the most recise. Its application provided results comparable with values detected by instrumental mode.