Volume expansion using pentastarch does not change gastric-arterial CO2 gradient or gastric intramucosal pH in patients who have sepsis syndrome

Objective: In hypovolemic patients with sepsis syndrome, to determine the e ffects of colloid volume infusion using 10% pentastarch on abnormal gastric tonometer measurements (gastric intramucosal CO2 tension, gastric intramuc osal-arterial Pco(2) gradient, and gastric intramucosal pH [pHi]) and on ca rdiac index, global oxygen delivery, and hemoglobin. Design: Prospective prepost intervention study. Setting: Tertiary care, university-affiliated 15-bed general systems intens ive care unit. Patients: Patients were studied who had sepsis syndrome, who had pulmonary arterial catheters in place, who were hypovolemic (pulmonary arterial occlu sion pressure [PAOP] <15 mm Hg), and who had a gastric arterial Pco(2) grad ient >10 mm Hg. Interventions: Baseline measurements of gastric intramucosal CO2 tension, g astric intramucosal-arterial Pco(2) gradient, and pHi, as well as arterial lactate, pulmonary arterial occlusion, central venous and systemic arterial pressures, thermodilution cardiac output, and temperature. Boluses of 500 mt pentastarch were administered to a total of 1000 mt or until PAOP was >1 8 mm Hg, Measurements were repeated at 30 mins and 120 mins postinfusion of pentastarch. Main Results: Volume infusion using pentastarch did not change gastric Pco( 2), gastric-arterial Pco(2) gradient, or pHi. Volume expansion with pentast arch significantly increased cardiac index, global oxygen delivery, and PAO P. Administration of pentastarch decreased hemoglobin and arterial lactate at 30 mins but not at 120 mins. Conclusions: Volume expansion using a colloidal solution of 10% pentastarch does not change abnormal intramucosal CO2 tension, gastric-arterial Pco(2) gradient, or pHi in critically ill hypovolemic patients who have sepsis sy ndrome despite increasing cardiac index, oxygen delivery, and pulmonary art ery occlusion pressure.