Matched Cohort Analysis of the Effects of Limb Remote Ischemic Conditioning in Patients with Aneurysmal Subarachnoid Hemorrhage
- 207 Downloads
Remote ischemic conditioning (RIC) is a powerful innate response to transient subcritical ischemia that protects against severe ischemic insults at distant sites. We have previously shown the safety and feasibility of limb RIC in aneurysmal subarachnoid hemorrhage (aSAH) patients, along with changes in neurovascular and cerebral metabolism. In this study, we aim to detect the potential effect of an established lower-limb conditioning protocol on clinical outcomes of aSAH patients. Neurologic outcome (modified Rankin Scale (mRS)) of patients enrolled in a prospective trial (RIPC-SAH) was measured. A matching algorithm was applied to identify control patients with aSAH from an institutional departmental database. RIC patients underwent four lower-limb conditioning sessions, consisting of four 5-min cycles per session over nonconsecutive days. Good functional outcome was defined as mRS of 0 to 2. The study population consisted of 21 RIC patients and 61 matched controls. There was no significant intergroup difference in age, gender, aneurysm location, clipping vs coiling, Fisher grades, Hunt and Hess grades, or vasospasm. RIC was independently associated with good outcome (OR 5.17; 95 % confidence interval (CI) 1.21–25.02). RIC also showed a trend toward lower incidence of stroke (28.6 vs. 47.5 %) and death (4.8 vs. 19.7 %). Lower-limb RIC following aSAH appears to have a positive effect in the functional outcomes of patients with aSAH. While this effect is consistent with prior preclinical studies, future trials are necessary to conclusively evaluate the effects of RIC for aSAH.
KeywordsAneurysm Neurologic outcomes Remote ischemic preconditioning Stroke Subarachnoid hemorrhage
Compliance with Ethical Standards
The authors have no personal, financial, or institutional interest in any of the drugs, materials, or devices described in this article. This research involved human participants. This study was conducted with Institutional Review Board approval, and participants gave informed consent before taking part. All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2008 (5).
Conflict of Interest
The authors declare that they have no competing interests.
This work is supported by the Ruth and Raymond Stotter Endowed Chair in Neurosurgery and the National Institutes of Health National Institute of Neurological Disorders and Stroke award K23NS079477.
- 16.Gonzalez NR, Boscardin WJ, Glenn T, Vinuela F, Martin NA. Vasospasm probability index: a combination of transcranial Doppler velocities, cerebral blood flow, and clinical risk factors to predict cerebral vasospasm after aneurysmal subarachnoid hemorrhage. J Neurosurg. 2007;107:1101–12. doi: 10.3171/JNS-07/12/1101.CrossRefPubMedGoogle Scholar
- 17.Oskouian RJ, Martin NA, Lee JH, Glenn TC, Guthrie D, Gonzalez NR, et al. Multimodal quantitation of the effects of endovascular therapy for vasospasm on cerebral blood flow, transcranial Doppler ultrasonographic velocities, and cerebral artery diameters. Neurosurgery. 2002;51:30–43. doi: 10.1097/00006123-200207000-00005.CrossRefPubMedGoogle Scholar
- 20.Kelsey JL, Whittemore AS, Evans AS, Thompson WD. Methods in observational epidemiology. New York: Oxford University Press; 1996.Google Scholar