Transplant Trial Watch

Bicarbonate ringer's solution could improve the intraoperative acid-base equilibrium and reduce hepatocellular enzyme levels after deceased donor liver transplantation: a randomized controlled study.

Li, Q., et al.

BMC Anesthesiology 2023; 23(1): 418.


Aims
To assess if using bicarbonate ringer’s solution improved acid-base balance and hepatocellular enzymes during deceased donor liver transplant compared with acetate ringer’s solution.

Interventions
The intraoperative goal-directed fluid management was randomised to either acetate ringer’s solution (AR) or bicarbonate ringer’s solution (BR).

Participants
69 adult liver transplant recipients

Outcomes
The primary outcomes were arterial pH, base excess, pCO2, glucose and lactate during the anhepatic phase (T1), immediately post-reperfusion (T2) and 30minutes after reperfusion. The secondary outcomes were volume of 5% bicarbonate required during surgery, post-reperfusion syndrome, length or ICU and hospital stay, bilirubin, AST, γ-GT, INR, and creatinine at 7 and 30 days postoperatively, and the rate of RRT.

Follow-up
Duration of hospital admission

CET Conclusions
This modest sized double blinded randomised controlled trial demonstrated that with the use of bicarbonate Ringer’s solution (BR) instead of acetate Ringer’s (AR) for deceased donor orthotopic liver transplant, the intra-operative acid-base balance could be more tightly controlled. Within the anhepatic phase and immediately post-reperfusion the use of BR limited the acidosis compared with AR, with a pH of 7.34 vs 7.29 (p=0.007) and 7.32 vs 7.21 (p=0.001) respectively. This reduction in acidosis, particularly within the anhepatic period reduces the burden on the liver upon reperfusion, and the authors speculate that this could result in reduced hepatocellular injury. They found a statistically significant difference in day 7 AST as their marker of hepatocellular injury, however there were no other differences in other liver enzymes, bilirubin or INR. AST is known to be far weaker than both bilirubin and INR in terms of its correlation with longer term outcomes and given the follow-up here was limited to only hospital stay, I think to associate the control of pH and reduced AST with potential longer-term benefit is unreasonable. There was also no benefit seen in the length of hospital or ITU stay. The number which experienced post reperfusion syndrome was numerically higher in the acetate group, though it was not statistically significant. They are missing some data that would have been of potential interest, such as bicarbonate level, haemodynamic data during the operation, intra-operative coagulation (TEG) and longer-term graft outcomes. The study was well designed, and explored a physiologically interesting concept with results that point towards a potential benefit, but is limited by its sample size and short-term follow-up.

Jadad score
4

Data analysis
Modified intention-to-treat analysis

Allocation concealment
Yes

Trial registration
ChiCTR2100050486

Funding source
Non-industry funded