Influence of goal-directed therapy with balanced crystalloid-colloid or unbalanced crystalloid solution on base excess.

Objective To investigate changes in standard base excess (SBE) when administering two different infusion regimens for elective hip replacement within a goal-directed haemodynamic algorithm. Methods This prospective, double-blind, randomized, controlled study enrolled patients scheduled for primary hip replacement surgery, who were randomized to receive either an unbalanced crystalloid (chloride: 155.5mmol/l) or a 1:1 mixture of a balanced crystalloid and a balanced colloid (6% w/v hydroxyethyl starch 130/0.42; chloride: 98 and 112mmol/l, respectively). Fluid management was goal-directed to optimize stroke volume using oesophageal Doppler. Results A total of 40 patients (19 female/21 male) participated in the study. After surgery, median (25-75% percentiles) SBE was significantly lower in the unbalanced group compared with the balanced group: -2.0mmol/l (-3.1 to -1.1) versus -0.4mmol/l (-1.2 to 0.7), respectively. This difference was mainly due to greater plasma chloride concentrations in the unbalanced group. The amount of study medication required to reach haemodynamic stability (median 1200ml) did not differ between the two groups. Conclusion SBE decreased in the unbalanced group without influence on fluid requirements and haemodynamic stability.