Thorac Cardiovasc Surg 2016; 64(07): 569-574
DOI: 10.1055/s-0035-1566128
Original Cardiovascular
Georg Thieme Verlag KG Stuttgart · New York

Dynamic Cerebral Autoregulation after Cardiopulmonary Bypass

Claus Behrend Christiansen
1  Centre of Inflammation and Metabolism, University Hospital Rigshospitalet, Copenhagen, Denmark
2  Department of Anaesthesiology and Intensive Care, Nordsjællands Hospital, Copenhagen, Denmark
,
Ronan M. G. Berg
1  Centre of Inflammation and Metabolism, University Hospital Rigshospitalet, Copenhagen, Denmark
3  Department of Clinical Physiology, Nuclear Medicine & PET, University Hospital Rigshospitalet, Copenhagen, Denmark
,
Ronni Plovsing
4  Department of Intensive Care 4131, University Hospital Rigshospitalet, Copenhagen, Denmark
5  Department of Anaesthesiology and Intensive Care, Køge Hospital, Køge, Denmark
,
Andreas Ronit
6  Department of Infectious Diseases, University Hospital Rigshospitalet, Copenhagen, Denmark
,
Niels-Henrik Holstein-Rathlou
7  Renal and Vascular Research Section, Department of Biomedical Sciences, University of Copenhagen, Faculty of Health Sciences, Copenhagen, Denmark
,
Stig Yndgaard
8  The Heart Centre, University Hospital Aarhus, Aarhus, Denmark
,
Kirsten Møller
9  Neurointensive Care Unit 2093, Department of Neuroanaesthesia, University Hospital Rigshospitalet, Copenhagen, Denmark
› Author Affiliations
Further Information

Publication History

06 July 2015

14 September 2015

Publication Date:
26 October 2015 (online)

Abstract

Background Cerebral hemodynamic disturbances in the peri- or postoperative period may contribute to postoperative cognitive dysfunction (POCD) in patients undergoing coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB). We therefore examined dynamic cerebral autoregulation (dCA) post-CPB and changes in neurocognitive function in patients that had undergone CABG.

Materials and Methods We assessed dCA by transfer function analysis of spontaneous oscillations between arterial blood pressure and middle cerebral artery blood flow velocity measured by transcranial Doppler ultrasound in eight patients 6 hours after the cessation of CPB; 10 healthy volunteers served as controls. Neurocognitive function was assessed by four specific tests 1 day prior to and 3 days after CPB.

Results Even though patients exhibited systemic inflammation and anemic hypoxemia, dCA was similar to healthy volunteers (gain: 1.24 [0.94–1.49] vs. 1.22 [1.06–1.34] cm mm Hg−1 s−1, p = 0.97; phase: 0.33 [0.15–0.56] vs. 0.69 [0.50–0.77] rad, p = 0.09). Neurocognitive testing showed a perioperative decline in the Letter Digit Coding Score (p = 0.04), while weaker dCA was associated with a lower Stroop Color Word Test (rho =  − 0.90; p = 0.01).

Discussion and Conclusion We found no changes in dCA 6 hours after CPB. However, based on the data at hand, it cannot be ruled out that changes in dCA predispose to POCD, which calls for larger studies that assess the potential impact of dCA in the early postoperative period on POCD.