Cerebral injury after cardiac surgery - Identification of a group at extraordinary risk

Background and Purpose-Cerebral injury after cardiac surgery is now recogni zed as a serious and costly healthcare problem mandating immediate attentio n. To effect solution, those subgroups of patients at greatest risk must be identified, thereby allowing efficient implementation of new clinical stra tegies. No such subgroup has been identified; however, patients undergoing intracardiac surgery are thought to be at high risk, but comprehensive data regarding specific risk, impact on cost, and discharge disposition are not available. Methods-We prospectively studied 273 patients enrolled from 24 diverse US m edical centers, who were undergoing intracardiac and coronary artery surger y. Patient data were collected using standardized methods and included clin ical, historical, specialized testing, neurological outcome and autopsy dat a, and measures of resource utilization. Adverse outcomes were defined a pr iori and determined after database closure by a blinded independent panel. Stepwise logistic regression models were developed to estimate the relative risks associated with clinical history and intraoperative and postoperativ e events. Results-Adverse cerebral outcomes occurred in 16% of patients (43/273), bei ng nearly equally divided between type I outcomes (8.4%; 5 cerebral deaths, 16 nonfatal strokes, and 2 new TIAs) and type II outcomes (7.3%; 17 new in tellectual deterioration persisting at hospital discharge and 3 newly diagn osed seizures). Associated resource utilization was significantly increased -prolonging median intensive care unit stay from 3 days (no adverse cerebra l outcome) to 8 days (type I; P<0.001) and from 3 to 6 days (type II; P<0.0 01), and increasing hospitalization by 50% (type II, P=0.04) to 100% (type I, P<0.001). Furthermore, specialized care after hospital discharge was fre quently necessary in those with type I outcomes, in that only 31% returned home compared with 85% of patients without cerebral complications (P<0.001) . Significant risk factors for type I outcomes related primarily to embolic phenomena, including proximal aortic atherosclerosis, intracardiac thrombu s, and intermittent clamping of the aorta during surgery. For type II outco mes, risk factors again included proximal aortic atherosclerosis, as well a s a preoperative history of endocarditis, alcohol abuse, perioperative dysr hythmia or poorly controlled hypertension, and the development of a low-out put state after cardiopulmonary bypass. Conclusions-These prospective multicenter findings demonstrate that patient s undergoing intracardiac surgery combined with coronary revascularization are at formidable risk, in that 1 in 6 will develop cerebral complications that are frequently costly and devastating. Thus, new strategies for periop erative management-including technical and pharmacological interventions-ar e now mandated for this subgroup of cardiac surgery patients.