Remote Ischaemic Preconditioning Reduces Kidney Injury Biomarkers in Patients Undergoing Open Surgical Lower Limb Revascularisation: A Randomised Trial

Abstract

Background and aims: Perioperative kidney injury affects 12.7% of patients undergoing lower limb revascularisation surgery. Remote ischaemic preconditioning (RIPC) is a potentially protective procedure against organ damage and consists of short nonlethal episodes of ischaemia. The main objective of this substudy was to evaluate the effect of RIPC on kidney function, inflammation, and oxidative stress in patients undergoing open surgical lower limb revascularisation. Materials and Methods. This is a subgroup analysis of a randomised, sham-controlled, double-blinded, single-centre study. A RIPC or a sham procedure was performed noninvasively along with preparation for anaesthesia in patients undergoing open surgical lower limb revascularisation. The RIPC protocol consisted of 4 cycles of 5 minutes of ischaemia, with 5 minutes of reperfusion between every episode. Blood was collected for analysis preoperatively, 2, 8, and 24 hours after surgery, and urine was collected preoperatively and 24 hours after surgery.

Results: Data of 56 patients were included in the analysis. Serum creatinine, cystatin C, and beta-2 microglobulin increased, and eGFR decreased across all time points significantly more in the sham group than in the RIPC group (p = 0.021, p = 0.021, p = 0.021, p = 0.021, p = 0.021.

Conclusions: Our finding of reduced release of kidney injury biomarkers may indicate the renoprotective effect of RIPC in patients undergoing open surgical lower limb revascularisation. The trial is registered with ClinicalTrials.gov NCT02689414.

Figure 1

Patients' flow chart. After randomisation, there were 28 patients in the RIPC group and 29 patients in the sham group who underwent lower limb revascularisation surgery; of these patients, 1 patient dropped out from the sham group.

Figure 2

Statistically significant changes between the sham group and the RIPC group—changes in creatinine, estimated glomerular filtration rate (eGFR), urea, cystatin C, beta-2 microglobulin, and the ratio of urinary isoprostanes to creatinine. ^∗p value for the change in the RIPC group; ^∗∗p value for the change in the sham group; ^∗∗∗p value for the changes between the groups.