Cardiac preload, splanchnic perfusion, and their relationship during resuscitation in trauma patients.

Introduction: Low gastric intramucosal pH (pHi) after shock resuscitation is associated with organ dysfunction and death in trauma patients. However, the relationship between hemodynamic performance, global oxygen transport, and pHi is unclear. Our purpose was to evaluate the relationship between intravascular volume status, splanchnic hypoperfusion, and outcome after shock resuscitation in trauma patients. Design/Setting: Cohort study of 79 consecutive critically ill patients at a Level I trauma center stratified by normal (NORM, ≥ 7.32) or low (LOW, < 7.32) pHi when lactate normalized (< 2.2 mmol/L). Main Outcome Measures: Differences during resuscitation in mean values of right ventricular end-diastolic volume index (RVEDVI), pulmonary artery occlusion pressure, cardiac index, oxygen delivery index, and oxygen consumption index. The incidence of multiple organ failure and death in the NORM and LOW groups were analyzed via odds ratio and X 2 . Results: Patients in the NORM group In = 45) had a lower incidence of multiple organ failure (4 of 45 vs. 11 of 34, odds ratio 5.0, p < 0.01) and death (5 of 45 vs. 11 of 34, odds ratio 3.8, p < 0.05) than patients in the LOW group In = 34). NORM patients had a higher initial RVEDVI (116 ± 31 vs. 95 ± 25 mL/m 2 , p < 0.001) and maintained a significantly higher RVEDVI (114 ± 27 vs. 97 ± 17 mL/m 2 , p = 0.003) throughout resuscitation than the LOW group did. There were no differences in the other studied variables. Conclusions: Supranormal levels of preload during shock resuscitation are associated with better outcome. Maintaining a RVEDVI higher than 100 mL/m 2 during shock resuscitation may be of benefit in critically injured patients.