Comparative Effectiveness of Preventive and Treatment Interventions for Cerebral Hyperperfusion Syndrome Following Bypass Surgery

Abstract

Although cerebral hyperperfusion syndrome (CHS) remains a major complication of bypass surgery that can lead to severe neurological morbidity and mortality, data regarding its prevention and treatment have not been assorted until date. Thus, we systematically reviewed the literature, to assess available data and evaluate whether any conclusions can be drawn regarding the effectiveness of utilized interventions on either preventing or treating bypass related CHS. We systematically reviewed PubMed & Cochrane Library from September 2008 to September 2018 according to PRISMA, to collect data regarding the effectiveness of pharmacologic interventions on the prevention (PRE) and treatment (TRE) of bypass-related CHS. We categorized interventions regarding their class of drugs and their combinations and calculated overall pooled estimates of the proportions of CHS development or improvement through random-effects meta-analyses of proportions using a Freeman-Tukey double arcsine transformation. Our search yielded 646 studies of which 40 fulfilled inclusion criteria. Meta-analysis of PRE included 23 studies/2041 cases. In group [A] (BP control) 202 out of 1174 pretreated cases developed CHS (23.3% pooled estimate; 95% CI 9.9-39.4), in group [B] (BP control + Free Radical Scavenger (FRS)) 10/263 pretreated cases developed CHS (0.3%; 95% CI 0.0-14.1), in group [C] (BP control + antiplatelet) 22/204 pretreated cases developed CHS (10.3%; 95% CI 5.1-16.7), and in group [D] (BP control + Postoperative sedation) 29/400 pretreated cases developed CHS (6.8%; 95% CI 4.4-9.6)]. Meta-analysis of TRE included 29 studies/144 cases that developed CHS. Pooled estimates of improvement ranged from 92.1% to 100.0%. Our data suggest that BP control alone as a pretreatment has not been proven effective in preventing CHS. However, BP control along with either postoperative sedation or an FRS or an antiplatelet agent seem to reduce the incidence of CHS. Once CHS has developed, BP control and/or FRS administration may ameliorate symptoms.