Impact of conventional vs. goal-directed fluid therapy on urethral tissue perfusion in patients undergoing liver surgery: A pilot randomised controlled trial.

Abstract

BACKGROUND\nAlthough fluid administration is a key strategy to optimise haemodynamic status and tissue perfusion, optimal fluid administration during liver surgery remains controversial.\n\n\nOBJECTIVE\nTo test the hypothesis that a goal-directed fluid therapy (GDFT) strategy, when compared with a conventional fluid strategy, would better optimise systemic blood flow and lead to improved urethral tissue perfusion (a new variable to assess peripheral blood flow), without increasing blood loss.\n\n\nDESIGN\nSingle-centre prospective randomised controlled superiority study.\n\n\nSETTING\nErasme Hospital.\n\n\nPATIENTS\nPatients undergoing liver surgery.\n\n\nINTERVENTION\nForty patients were randomised into two groups: all received a basal crystalloid infusion (maximum 2\u200aml\u200akg-1\u200ah-1). In the conventional fluid group, the goal was to maintain central venous pressure (CVP) as low as possible during the dissection phase by giving minimal additional fluid, while in the posttransection phase, anaesthetists were free to compensate for any presumed fluid deficit. In the GDFT group, patients received in addition to the basal infusion, multiple minifluid challenges of crystalloid to maintain stroke volume (SV) variation less than 13%. Noradrenaline infusion was titrated to keep mean arterial pressure more than 65\u200ammHg in all patients.\n\n\nMAIN OUTCOME MEASURE\nThe mean intra-operative urethral perfusion index.\n\n\nRESULTS\nThe mean urethral perfusion index was significantly higher in the GDFT group than in the conventional fluid group (8.70 [5.72 to 13.10] vs. 6.05 [4.95 to 8.75], P\u200a=\u200a0.046). SV index (ml\u200am-2) and cardiac index (l\u200amin-1\u200am-2) were higher in the GDFT group (48\u200a±\u200a9 vs. 33\u200a±\u200a7 and 3.5\u200a±\u200a0.7 vs. 2.4\u200a±\u200a0.4, respectively; P\u200a<\u200a0.001). Although CVP was higher in the GDFT group (9.3\u200a±\u200a2.5 vs. 6.5\u200a±\u200a2.9\u200ammHg; P\u200a=\u200a0.003), intra-operative blood loss was not significantly different in the two groups.\n\n\nCONCLUSION\nIn patients undergoing liver surgery, a GDFT strategy resulted in a higher mean urethral perfusion index than did a conventional fluid strategy and did not increase blood loss despite higher CVP.\n\n\nTRIAL REGISTRATION\nNCT04092608.