Dependency of the O2 consumption/O 2 transport relationship on amino acid supply in sepsis

In sepsis tissue O2 uptake may be abnormally limited because of a depressed O2 consumption/O2 transport relationship. This study has been performed to assess patterns of O2 consumption, CO2 production and O2 transport in septic patients undergoing total parenteral nutrition; more in particular, this study has investigated the interdependence between the patterns of blood O2 uptake and simultaneous CO2 release, and the availability of substrates (amino acids, glucose and fat). It has been shown that the O2 consumption/O2 transport relationship is significantly influenced by the exogenous amino acid load, which tends to increase O2 uptake and O2 consumption at any given O2 transport, thus suggesting a favourable effect of amino acid administration on energy metabolism. The data on CO2 production and CO2 release, in addition to reconfirming the results of previous studies, have shown that the changes in O2 uptake and in CO2 production mediated by substrate doses have a quantifiable impact on blood O2-CO2 exchange interactions.