Impact of remote ischemic preconditioning preceding coronary artery bypass grafting on inducing neuroprotection

Abstract

Background: Neurological complications after coronary artery bypass grafting (CABG) reduce quality of life, increase mortality, and inflate resource utilization. The risk of postoperative neurological complications parallels the increasing risk burden of the contemporary patient population. We evaluated the efficacy of remote ischemic preconditioning (RIPC) on inducing neuroprotection.Methods: Seventy patients undergoing first-time CABG were randomly assigned to RIPC or a sham procedure. Structural brain magnetic resonance imaging (MRI) was complemented with functional connectivity MRI to gain a whole-brain global connectivity analysis. Paired neurocognitive and MRI data were acquired pre-and postoperatively. The primary end point was a composite of new ischemic brain lesions and neurocognitive impairment. Secondary end points included brain connectivity profiles, pooled ischemic volumes, and individual components of the primary outcome. The Shapiro-Wilk test was used to determine whether a data set followed a normal distribution. The Fisher exact test was used to calculate the measures of association for categorical variables, whereas continuous data were tested with either the Mann-Whitney U test or the Student t test.Results: There was no between-group difference in the incidence of the primary end point (9 [27%] in the RIPC group vs 8 [24%] in the control group, odds ratio, 1.17 [95% confidence interval, 0.34-4.06]; P ¼ 1.0). Although RIPC did not reduce the incidence of brain ischemia (8/33 [24%] vs 7/33 [21%]; P ¼ 1.0), the pooled ischemic volume was lower in the RIPC group (157 [interquartile range, 125-231] vs 777 [interquartile range, 564-965] mm 3 ; P ¼ .004). Postoperative neurocognition was marginally superior in the RIPC group as evidenced by a lower absolute number of abnormal neurocognitive tests in the RIPC group (7/99 [7%] vs 16/99 [16%]; odds ratio, 0.40 [95% confidence interval, 0.14-1.09]; P ¼ .074). Robust reductions of functional connectivity profiles for the associative thalamus were documented in both groups, irrespective of RIPC (RIPC group, t ¼ 3.31; P <.01; and the control group, t ¼ 3.52; P <.01).Conclusions: Silent brain ischemia occurs frequently after CABG. RIPC did not reduce the incidence of the primary outcome. However, RIPC significantly RIPCAGE study summary. Brain-wide postoperative reductions in associative thalamic functional connectivity (shown in green). Central MessageAlthough RIPC did not reduce the incidence of new brain ischemia, it reduced its pooled volume. Surgery adversely affected global brain connectivity, with RIPC conferring no demonstrable protection. PerspectiveIschemic preconditioning mobilizes the endogenous potential for protection against ischemia incurred by alternating periods of sublethal ischemia and reperfusion. Neuronal injury occurs in response to cardiac surgical interventions at the structural and functional levels. RIPC might have the potential to alleviate brain ischemic cellular damage and might thus provide an additional layer of neuroprotect...

Remote Ischemic Preconditioning to Prevent Acute Kidney Injury After Cardiac Surgery: A Meta-Analysis of Randomized Controlled Trials

“…Patients with normal kidney function at baseline were included except one study that included patients with chronic kidney disease (CKD) who were scheduled for cardiac surgery (17). With regard to the surgery procedures, 20 studies included patients who received on-pump surgeries (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)30), while the remaining two studies included patients who received off-pump surgeries (29,31). Proportions of diabetic patients varied among the included studies, and patients with severe cardiac systolic function (left ventricular ejection fraction <30%) were rarely included.…”

“…Uninflated cuffs were used on patients in the control group. Most of the studies used the AKIN definition of AKI, while the RIFLE (13,19,28) and the KDIGO (18,20,30,31) definitions were used in three and four studies, respectively. Table 2 shows the details of study quality evaluation.…”

“…Although, these results were also inconsistent (35). Many RCTs have been published since 2016 (22,(24)(25)(26)(27)(28)(29)(30)(31), warranting an updated meta-analysis. In addition, the potential impacts of study and patient features on the efficacy of RIPC on postoperative AKI in these patients were rarely analyzed.…”

Effect of Remote Ischemic Conditioning on Bleeding Complications in Surgery: A Systematic Review and Meta-Analysis

“…A subgroup of 1,951 patients from 18 trials underwent cardiac surgery. [27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44] The remaining 1,853 patients were included in 14 trials in various surgical settings: organ transplant donors or recipients (five trials), [45][46][47][48][49] tumor resection (five trials), 13,[50][51][52][53] abdominal aortic aneurysm repair (two trials), 54,55 and orthopaedic surgery (two trials) 56,57 (►Table 1). Preconditioning was the preferred study intervention used in 26 trials, 13,[28][29][30][31]33,34,[36][37][38][39][40][41][42][43][44][45][46]…”

Remote ischemic preconditioning for elective endovascular intracranial aneurysm repair: a feasibility study

“…RIPC has been demonstrated to reduce neural damage in experimental models of ischemic stroke, [10][11][12][13] and mitigate ischemic brain damage and neurological sequelae in humans after cardiac surgery. 14 RIPC has recently been applied in the setting of acute stroke, specifically intracranial atherosclerotic stenosis. 15,16 Previous studies showed the safety and feasibility of RIPC with extremely low numbers of side effects in aneurysmal subarachnoid hemorrhage, 17,18 acute ischemic stroke, 19,20 and in patients who undergo mechanical thrombectomy 20 and elective carotid endarterectomy.…”