A Systematic Review Of The Relationship Between Cerebral Hyperperfusion Syndrome After Carotid Endarterectomy And Postoperative Hypertension

Objective:Cerebral hyperperfusion syndrome (CHS) is a rare and severe perioperative complication of carotid endarterectomey (CEA). It manifests as postoperative ipsilateral severe headache, seizures, hemiparesis. And it could cause severe outcome such as intracranial hemorrhage (ICH) and death. Postoperative hypertension is thought one of the mechanisms of CHS. Consensus that whether to control blood pressure, blood pressure (BP) thresholds hasn’t been acquired by doctors. The evidence for the prevention of CHS through the control of BP is the focus of this article.Methods:The review was conducted by preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines in March2010. The search strategy is Hypertension OR blood pressure AND postoperative OR post operative AND cerebral hyperperfusion syndrome OR reperfusion syndrome OR intracerebral haemorrhage OR intracerebral hemorrhagic OR intracranial haemorrhage OR intracranial hemorrhage OR haemorrhagic stroke OR hrmorrhagic stroke OR seizures AND carotid endarterectomy. The inclusion and exclusion criteria are1) English publications searched by Pubmcd between1985and2012.2) Regarding humans in Westen country.3) CEA only and not stenting.4) Studies more than500patients when assessing the evidence that BP control could prevent CHS were selected.5) Studies which CHS was diagnosed on the basis of headache alone were excluded.Results:A total of31studies were identified by the strategy. Patient age range was39-93years. CHS presented with seizures in34%(17/50), hemiparesis in32%(16/50) or both in28%(14/50) of patients, confusion alone or with seizures or hemiparesis in28%(14/50). ICH presented with seizures in31%(11/36), hemiparesis in25%(9/36), both in31%(11/36) and reduced level of consciousness in13%(5/36). Following CEA, the incidence of severe hypertension was19%, that of cerebral hyperperfusion1.1%and ICH0.7%.81%of patients had severe hypertension at the onset of CHS or ICH. Contrasting with the control group, severe hypertension was found in a significantly greater proportion in CHS patients (p<0.000l, OR1995%CI9-41). The last recorded postoperative systolic BP (sBP)165mmHg (95%CI151-178mmHg, n=16). The mean sBP on presentation of CHS was189mmHg (95%CI183-196mmHg, n=44). Only one case was normotensive at presentation. Fifteen cases mentioned both the postoperative BP and BP at presentation with CHS. The shortest documented time from operation to symptoms was17hours. Average time to symptoms was the5th postoperative day (interquartile range IQR3-6days). A total of133/145(92%) of cases of CHS or ICH occurred in the first week. The latest case was at28days. Headache occurred in20%(110/612) of patients following CEA without CHS,59%(13/22) of patients with CHS and84%(32/38) of patients with ICH.Conclusion:There is currently level-3evidence for the prevention of ICH through control of postoperative BP. BP could be lowered to140mmHg. It is important that patients be not discharged with severe hypertension or an BP that is rising. From the available data, we suggest identifying the definition of CHS, thresholds and time of blood control. All the postoperative hypertension patients should accept the rigorous BP monitoring and venous antihypertensive medicines.