ObjectiveTo investigate the effect of the nitroglycerin-controlled low central venous pressure （CLCVP） technique on brain metabolic markers and cerebral blood oxygen saturation in patients undergoing laparoscopic hepatectomy for liver cancer， and to reduce the risk of neurological complications. MethodsA total of 105 patients who underwent elective laparoscopic hepatectomy for liver cancer in Haikou Hospital Affiliated to Xiangya Hospital of Central South University from April 2020 to May 2023 were enrolled and randomly divided into CLCVP group with 54 patients and non-CLCVP group with 51 patients. The patients in the CLCVP group were treated with the nitroglycerin CLCVP technique during surgery， while those in the non-CLCVP group were given conventional surgical treatment. The two groups were compared in terms of the following indicators： perioperative indicators； hemodynamic parameters and cerebral oxygen metabolism before anesthesia induction （T0）， at 5 minutes after anesthesia induction （T1）， at 5 minutes after the beginning of liver parenchyma dissection （T2）， at 5 minutes after the end of hepatectomy （T3）， and immediately after the end of surgery （T4）； the changes in liver function parameters after surgery； the incidence rate of adverse reactions. The independent-samples t test was used for comparison of continuous data between two groups， and the chi-square test was used for comparison of categorical data between two groups； the analysis of variance with repeated measures was used for comparison between multiple time points. ResultsCompared with the non-CLCVP group， the CLCVP group had significantly lower intraoperative blood loss and intraoperative fluid infusion volume （t=5.408 and 7.220， both P<0.05）， while there were no significant differences between the two groups in time of operation， anesthesia time， extubation time， resuscitation time and intraoperative urine volume （all P>0.05）. Compared with the data at T0， both groups had significant reductions in mean arterial pressure， heart rate， and central venous pressure during surgery （all P<0.05）， and compared with the non-CLCVP group， the CLCVP group had significantly lower mean arterial pressure and central venous pressure （P<0.05） and a significantly higher heart rate （P<0.05） at T2 and T3. Compared with the data at T0， both groups had a significant reduction in Ca-jvDO₂ at T2‍ ‍—‍ ‍T4 time points （all P<0.05）， while there was no significant difference in Ca-jvDO₂ between the two groups at each time point （all P>0.05）. Compared with the data at T0， the CLCVP group had a significant reduction in rSO₂ at T2‍ ‍—‍ ‍T4 time points （all P<0.05）， and the CLCVP group had a significantly lower level of rSO₂ than the non-CLCVP group at T2‍ ‍—‍ ‍T3 time points （both P<0.05）； there were no significant changes in CERO₂ and Djv-aBL in either group at each time point （all P>0.05）. At 3 and 7 days after surgery， both groups had significant increases in the liver function parameters of aspartate aminotransferase （AST）， alanine aminotransferase （ALT）， and total bilirubin （TBil） （all P<0.05）， and the CLCVP group had significantly lower levels of AST and ALT than the non-CLCVP group （all P<0.05）； there was no significant difference in TBil between the two groups at each time point （all P>0.05）. There was no significant difference in the incidence rate of perioperative complications between the two groups （χ²=0.729， P=0.394）. ConclusionThe application of the nitroglycerin CLCVP technique in laparoscopic hepatectomy for liver cancer can reduce the amount of intraoperative blood loss in patients， but it is necessary to further enhance the monitoring of cerebral blood oxygen saturation during surgery， so as to reduce the risk of neurological complications as much as possible.