Transplant Trial Watch

A randomized comparison between pulse pressure variation and central venous pressure in patients undergoing renal transplantation.

Goyal, V. K., et al.

Journal of Anaesthesiology Clinical Pharmacology 2021; 37(4): 628-632.


Aims
This study aimed to compare pulse pressure variation and central venous pressure to guide fluid therapy during renal transplantation.

Interventions
Participants were randomised into two groups: group A, in which patients administered intraoperative fluids guided by central venous pressure (control group); and group B, where patients administered intraoperative fluids guided by pulse pressure variation.

Participants
75 patients undergoing renal transplantation.

Outcomes
The primary endpoint was the incidence of delayed graft function. Secondary endpoints included the incidence of perioperative hypotension, pulmonary edema posttransplantation, lactic acidosis and tissue edema.

Follow-up
7 days post-operation

CET Conclusions
This small single centre RCT investigated different methods of fluid monitoring during living donor renal transplantation. Patients were randomised to CVP or pulse pressure variation (PPV) -guided fluid administration intraoperatively. Patients with PPV-guided fluid administration had less intraoperative fluid, and less post-operative oedema. There were no differences in graft function or DGF between groups. The authors conclude that PPV-guided fluid administration is superior. There are some issues with trial design that limit the strength of this conclusion. The study is powered to show a difference in delayed graft function, a rare outcome after living donor kidney transplantation. The authors cite a baseline rate of 1 in 10 in the CVP group, and present a power calculation that suggests that 35 patients per group are required to demonstrate a difference. This power calculation cannot be recreated – to demonstrate a difference in such a rare outcome would require a much larger sample size. The only real outcome difference, other than intraoperative fluid administration, is incidence of oedema. It is not clearly stated how this was assessed, and given the absence of blinding one has to question the validity of such a subjective outcome.

Jadad score
2

Data analysis
Per protocol analysis

Allocation concealment
No

Trial registration
N/A

Funding source
No funding received