Splanchnic and total body oxygen consumption differences in septic and injured patients.

The splanchnic and total body oxygen exchange and flow dynamics for injured patients (n = 7) and patients with sepsis and stable vital signs (n = 12) were studied. All patients were judged to be in the hyperdynamic phase of the stress response. In both patient groups 27% to 28% of the cardiac index was directed to the splanchnic circulation. However, in sepsis the splanchnic region consumed a significantly larger fraction (p less than 0.05) of the total body oxygen (43.8%) compared with that consumed in injury (30.2%). After injury, the regional splanchnic flow and oxygen consumption appeared to be well matched whereas in sepsis, a disproportionately higher oxygen consumption is found, which must be supplied by increasing blood oxygen extraction. This regional hypermetabolism of the splanchnic area probably results from the increased metabolic demand imposed by the various synthetic processes of this region. In addition, it is proposed that excessive discrepancy between splanchnic flow and oxygen demand may precipitate regional ischemia.