Background

Fluid therapy during major hepatic resection aims at minimizing fluids during the dissection phase to reduce central venous pressure, retrograde liver blood flow, and venous bleeding. This strategy, however, may lead to hyperlactatemia. The Acumen assisted fluid management system uses novel decision support software, the algorithm of which helps clinicians optimize fluid therapy. The study tested the hypothesis that using this decision support system could decrease arterial lactate at the end of major hepatic resection when compared to a more restrictive fluid strategy.

Methods

This two-arm, prospective, randomized controlled, assessor- and patient-blinded superiority study included consecutive patients undergoing major liver surgery equipped with an arterial catheter linked to an uncalibrated stroke volume monitor. In the decision support group, fluid therapy was guided throughout the entire procedure using the assisted fluid management software. In the restrictive fluid group, clinicians were recommended to restrict fluid infusion to 1 to 2 ml · kg−1 · h−1 until the completion of hepatectomy. They then administered fluids based on advanced hemodynamic variables. Noradrenaline was titrated in all patients to maintain a mean arterial pressure greater than 65 mmHg. The primary outcome was arterial lactate level upon completion of surgery (i.e., skin closure).

Results

A total of 90 patients were enrolled over a 7-month period. The primary outcome was lower in the decision support group than in the restrictive group (median [quartile 1 to quartile 3], 2.5 [1.9 to 3.7] mmol · l−1vs. 4.6 [3.1 to 5.4] mmol · l−1; median difference, −2.1; 95% CI, −2.7 to −1.2; P < 0.001). Among secondary exploratory outcomes, there was no difference in blood loss (median [quartile 1 to quartile 3], 450 [300 to 600] ml vs. 500 [300 to 800] ml; P = 0.727), although central venous pressure was higher in the decision support group (mean ± SD of 7.7 ± 2.0 mmHg vs. 6.6 ± 1.1 mmHg; P < 0.002).

Conclusions

Patients managed using a clinical decision support system to guide fluid administration during major hepatic resection had a lower arterial lactate concentration at the end of surgery when compared to a more restrictive fluid strategy. Future trials are necessary to make conclusive recommendations that will change clinical practice.

Editor’s Perspective
What We Already Know about This Topic
  • Dynamic measures of fluid responsiveness such as derived stroke volume, stroke volume index, stroke volume variation, and systemic vascular resistance index have been used to guide intraoperative fluid administration for many high-risk procedures
  • Restrictive fluid administration during specific portions of hepatic resection surgery has become the standard of care to reduce intraoperative bleeding but may be associated with hypoperfusion and hyperlactemia
  • It remains unclear whether the use of a proprietary fluid administration decision support system compared to a restrictive fluid strategy using standard dynamic fluid responsiveness measures can improve hyperlactemia after hepatic resection
What This Article Tells Us That Is New
  • Ninety patients undergoing major laparoscopic or open hepatic resection were randomized to a decision support or restrictive fluid strategy
  • Lactate levels at the end of surgery in the decision support group (median, 2.5 mM; interquartile range, 1.9 to 3.7) were lower than in the restrictive group (median, 4.6; interquartile range, 3.1 to 5.4) for a median difference of 2.1 mM (95% CI, −2.7 to −1.2; P < 0.001)
  • The exploratory secondary outcome of intraoperative estimated blood loss was not statistically significantly different between the decision support group (median, 450 ml; interquartile range, 300 to 600) compared to the restrictive fluid group (median, 500 ml; interquartile range, 300 to 800 ml; P = 0.727)