Intention to control low central venous pressure reduced blood loss during laparoscopic hepatectomy: A double-blind randomized clinical trial.

Background: Excessive intraoperative hemorrhage is a critical factor of poor prognoses after hepatectomy. Low central venous pressure during parenchymal transection is recognized to effectively reduce intraoperative hemorrhage in open procedures. However, the role of controlled low central venous pressure in laparoscopic hepatectomy is still controversial.

Methods: In the present randomized clinical trial, we set up a standard boundary of low central venous pressure according to our Pilot Study, then enrolled patients scheduled for elective laparoscopic hepatectomy and allocated them randomly to a group undergoing central venous pressure reduction by anesthesiologic interventions or a control group. The primary efficacy endpoint was total intraoperative blood loss and perioperative adverse events. Analyses were performed following the intention-to-treat principle, and patients and surgeons were blinded (ClinicalTrials.gov, Number: NCT03422913).

Results: Between January 2017 and October 2018, 146 out of 469 patients were randomized and eligible for inclusion in the final analyses. Based on the retrospective training cohort, we set a central venous pressure of 5 cm HO as a cutoff value (standard low central venous pressure). Compared with patients in the control group, those in the controlled low central venous pressure group had a significantly lower central venous pressure during resection (4.83 ± 3.41 cm HO vs 9.26 ± 3.38 cm HO; P < .001) and significantly reduced total intraoperative blood loss (188.00 ± 162.00 mL vs 346.00 ± 336.00 mL; P < .001). The perioperative adverse events were comparable in both study groups (P = .313).

Conclusion: The safety and efficacy of controlled low central venous pressure were demonstrated in complex laparoscopic hepatectomy for the first time by our study, and this technique is recommended to be applied routinely in laparoscopic hepatectomy.