Effect of injury and total parenteral nutrition on water and electrolytes of RBC, serum, muscle and liver tissue.

Trauma is associated with an increased rate of tissue catabolism which can lead to a heightened cellular requirement for regeneration of adenosine triphosphate (ATP) and to decreased activities of adenosine triphosphatases. The effect of severe trauma and total parenteral nutrition (TPN) on water and electrolyte levels in red cells, serum, muscle and liver was investigated. In this study, 16 subjects formed the normal control (control group). The injured group consisted of 8 subjects who suffered from severe trauma and/or post-operative complications with or without infection. The TPN group consisted of 8 subjects in a severe catabolic period who underwent TPN treatment. Blood, muscle and liver samples were obtained during surgical procedures. In red cells and serum, all measured electrolyte levels were within normal limits except the serum of the injured group which showed decreased calcium and increased magnesium levels. Muscle and liver tissue analyses for the injured group showed an increase in water content and sodium and chloride levels, but calcium, potassium and phosphate levels in muscle were decreased. Hepatic potassium and calcium levels, however, were both increased in the same group. In the TPN regimen, cell mass was restored, primarily in muscle, with a contraction of the water content. The restoration of electrolyte levels, especially potassium levels, in muscle during TPN reflected an increase in muscle cell mass.