Remote ischemic preconditioning for cerebral and cardiac protection during carotid endarterectomy: results from a pilot randomized clinical trial. Remote ischemic preconditioning for renal and cardiac protection during endovascular aneurysm repair: a randomized controlled trial. Remote ischemic preconditioning for renal protection during elective open infrarenal abdominal aortic aneurysm repair: randomized controlled trial. Remote ischemic preconditioning reduces myocardial and renal injury after elective abdominal aortic aneurysm repair: a randomized controlled trial.
Remote ischemic preconditioning (RIPC) is a physiological mechanism whereby brief ischemia-reperfusion episodes attenuate damage by subsequent prolonged ischemic insults. It reduces myocardial injury following cardiac and aortic aneurysm surgery. We aimed to determine whether RIPC affects neurological or cardiac injury following carotid endarterectomy (CEA). Patients were preconditioned using 10 minutes of lower limb ischemia-reperfusion. The primary neurological outcome was saccadic latency deterioration. The primary cardiac outcome measure was increased in serum troponin I >0.15 mg/dL. In all, 70 patients were randomized, of whom 55 completed the neurological surveillance protocol. Although there were fewer saccadic latency deteriorations in the RIPC arm, this did not reach statistical significance (32% versus 53%; P = .11). The primary cardiac outcome occurred in 1 patient in each arm (P = .97). There were no adverse events related to the preconditioning protocol. Remote ischemic preconditioning appears safe in patients with CEA. Large-scale trials are required to determine whether RIPC confers clinical benefits. To report a randomized clinical trial designed to determine if remote ischemic preconditioning (IP) has the ability to reduce renal and cardiac damage following endovascular aneurysm repair (EVAR).
                Forty patients (all men; mean age 76+/-7 years) with abdominal aortic aneurysms averaging 6.3+/-0.8 cm in diameter were enrolled in the trial from November 2006 to January 2008. Eighteen patients (mean age 74 years, range 72-81) were randomized to preconditioning and completed the full remote IP protocol; there were no withdrawals. Twenty-two patients (mean age 76 years, range 66-80) were assigned to the control group. Remote IP was induced using sequential lower limb ischemia. Serum and urinary markers of renal and cardiac injury were compared between the groups.
                Urinary retinol binding protein (RBP) levels increased 10-fold from a median of 235 micromol/L to 2356 micromol/L at 24 hours (p = 0.0001). There was a lower increase in the preconditioned group, from 167 micromol/L to 413 micromol/L at 24 hours (p = 0.04). The median urinary albumin:creatinine ratio was significantly lower in the preconditioned group at 24 hours (5 versus 8.8, p = 0.06). There were no differences in the rates of renal impairment or major adverse cardiac events.
                Remote preconditioning reduces urinary biomarkers of renal injury in patients undergoing elective EVAR. This small pilot trial was unable to detect an effect on clinical endpoints; further trials are warranted. We aimed to determine whether remote ischemic preconditioning (IP) reduces renal damage following elective open infrarenal abdominal aortic aneurysm (AAA) repair. Sequential common iliac clamping was used to induce remote IP in randomized patients. Urinary retinol binding protein (RBP) and albumin-creatinine ratio (ACR) were measured following induction and 3, 24, and 48 hours postoperatively. In controls (n = 22), median urinary RBP increased from 112 microg/mL (interquartile range [IQR] 96-173 microg/mL) preoperatively to 5919 microg/mL (IQR 283-17 788 microg/mL) at 3 hours. Preoperative urinary RBP in preconditioned patients was 96 microg/mL (IQR 50 to 229 microg/mL) preoperatively, rising to 1243 microg/mL (IQR 540 to 15400 microg/mL) at 3 hours. Although control patients' median urinary RBP level was 5 times greater at 3 hours, there were no statistically significant differences in renal outcome indices. This trial could not confirm that remote IP reduces renal injury following elective open aneurysm surgery. Myocardial and renal injury commonly contribute to perioperative morbidity and mortality after abdominal aortic aneurysm repair. Remote ischemic preconditioning (RIPC) is a phenomenon whereby brief periods of ischemia followed by reperfusion in one organ provide systemic protection from prolonged ischemia. To investigate whether remote preconditioning reduces the incidence of myocardial and renal injury in patients undergoing elective open abdominal aortic aneurysm repair, we performed a randomized trial. METHOD AND RESULTS; Eighty-two patients were randomized to abdominal aortic aneurysm repair with RIPC or conventional abdominal aortic aneurysm repair (control). Two cycles of intermittent crossclamping of the common iliac artery with 10 minutes ischemia followed by 10 minutes reperfusion served as the RIPC stimulus. Myocardial injury was assessed by cardiac troponin I (>0.40 ng/mL), myocardial infarction by the American College of Cardiology/American Heart Association definition and renal injury by serum creatinine (>177 micromol/L) according to American Heart Association guidelines for risk stratification in major vascular surgery. The groups were well matched for baseline characteristics. RIPC reduced the incidence of myocardial injury by 27% (39% versus 12% [95% CI: 8.8% to 45%]; P=0.005), myocardial infarction by 22% (27% versus 5% [95% CI: 7.3% to 38%]; P=0.006), and renal impairment by 23% (30% versus 7%; [95% CI: 6.4 to 39]; P=0.009). Multivariable analysis revealed the protective effect of RIPC on myocardial injury (OR: 0.22, 95% CI: 0.07 to 0.67; P=0.008), myocardial infarction (OR: 0.18, 95% CI: 0.04 to 0.75; P=0.006) and renal impairment were independent of other covariables.
                In patients undergoing elective open abdominal aortic aneurysm repair, RIPC reduces the incidence of postoperative myocardial injury, myocardial infarction, and renal impairment.