Remote Ischemic Preconditioning Prevents Postoperative Acute Kidney Injury After Open Total Aortic Arch Replacement: A Double-Blind, Randomized, Sham-Controlled Trial
Hypothesis: Remote ischemic preconditioning (RIPC) will prevent postoperative acute kidney injury in patients after open total aortic arch replacement
Methods: Randomized, double blinded, sham-controlled trial in which 130 patients were assigned to the RIPC intervention arm (N = 64) or the sham control arm (N = 65). Both groups were induced with standard anesthetic drugs, and then the intervention was performed. RIPC group underwent 4 cycles of 5-minute right upper arm ischemia with a BP cuff at high inflation pressure (with 5 minutes of cuff deflation and reperfusion between cycles), whereas the sham group underwent 4 cycles of 5-minute right upper arm pseudo-ischemia with a BP cuff inflated to only 20 mmHg, with the same ‘reperfusion’ time between.
Results: There was less AKI in the RIPC group (55.4%) compared to the sham group (73.8%), with an ARR of 18.5% (p = .028). They also observed less severe acute kidney injury (35.4% v 10.8%, p = .001) and a shorter duration of mechanical ventilation (18h v 25h, p = .01) in the RIPC group v the sham-control group.
Strengths:
Randomized, double blinded
Few exclusion criteria
Low dropout rate
Intention to treat analysis
Similar baseline demographics
Weaknesses:
Single center study, limiting external validity
Mostly male patients
No proposed mechanism of action to explain results
Some secondary outcomes lacked significant power
Key Point: Remote ischemic preconditioning prevented AKI after open total arch replacement (especially severe AKI), and shortened mechanical ventilation duration.