Impact of single clamp versus double clamp technique on neurologic outcome

Background Atherosclerotic disease of the aorta has been identified as a risk factor for neurologic complications following coronary artery bypass grafting (CABG) due to the use of aortic clamping and manipulation. We reviewed a change from double clamp to single clamp technique to determine its impact on neurologic outcomes. Methods Patients undergoing isolated CABG by a single surgeon were identified as having double clamp technique (DCT) (aortic cross clamp + sidebiting clamp) or single clamp technique (SCT) (aortic cross clamp only). Data were collected by study personnel and clinicians to determine stroke and neurologic injury (confusion, delirium, seizure, altered mental status, and agitation) outcomes for 461 patients. Results Two hundred seventy-two patients had DCT and 189 patients had SCT performed. There were no differences in mean age, previous stroke, hypertension, or diabetes. Intraoperatively, patients with SCT had shorter bypass times (115 minutes vs 128 minutes, p = 0.001), longer aortic cross clamp time (89 minutes vs 80 minutes, p = 0.001), fewer coronary grafts (2.8 vs 3.1, p = 0.001), and had higher mean arterial blood pressure on cardiopulmonary bypass (76 mm Hg vs 69 mm Hg, p = 0.001). Postoperatively, the SCT group had fewer strokes (1.1% vs 2.9%, NS), and neurologic injuries (3.2% vs 9.6%, p = 0.008). By multivariate analysis, the factors that were related to neurologic injury were DCT (p = 0.04), age (p = 0.001), and number of coronary grafts (p = 0.03). Conclusions This experience suggests that the use of the SCT may be important in reducing neurologic injury following CABG.