Tailoring cardiopulmonary bypass pump flow and mean arterial pressure to maintain renal oxygenation

Background Cerebral embolization is a primary cause of cardiac surgical neurologic morbidity. During cardiopulmonary bypass (CPB), there are well-defined periods of embolic risk. In theory, cerebral embolization might be reduced by an increase in pump flow during these periods. The purpose of this study was to determine the CPB flow-embolization relation in a canine model. Methods Twenty mongrel dogs underwent CPB at 35 degrees C with alpha-stat management and a fentanyl-midazolam anesthetic. In each animal, CPB flow was adjusted to achieve a mean arterial pressure of 65-75 mmHg. During CPB, an embolic load of 1.2 x 10(5) 67 microm fluorescent microspheres was injected into the arterial inflow line. Before and after embolization, cerebral blood flow was determined using 15-microm microspheres. Tissue was taken from 12 brain regions and microspheres were recovered. The relation between pump flow and embolization/g of brain was determined. Results The mean arterial pressure at embolization was 67 +/-4 mmHg, and the range of pump flow was 0.9-3.5 l x min(-1)x m(-2). Cerebral blood flow was independent of pump flow. At lower pump flow, the percentage of that flow delivered to the brain increased. There was a strong inverse relation between pump flow and cerebral embolization (r = -0.708, P < 0.000 by Spearman rank order correlation). Conclusions Cerebral embolization is determined by the CPB flow. At an unchanged mean arterial pressure, as pump flow is reduced, a progressively greater proportion of that flow is delivered to the brain.

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Support of mean arterial pressure during tepid cardiopulmonary bypass: Effects of phenylephrine and pump flow on systemic oxygen supply and demand

Journal of Cardiothoracic and Vascular Anesthesia ◽

10.1016/s1053-0770(99)90217-3 ◽

1999 ◽

Vol 13 (4) ◽

pp. 441-445 ◽

Cited By ~ 4

Author(s):

Walter Plöchl ◽

Thomas A. Orszulak ◽

David J. Cook ◽

Rajbir S. Sarpal ◽

David L. Dickerman

Keyword(s):

Cardiopulmonary Bypass ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Oxygen Supply ◽

Supply And Demand ◽

Pump Flow ◽

Systemic Oxygen

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CARDIOPULMONARY BYPASS (CPB) PUMP FLOW DOES NOT AFFECT CEREBRAL BLOOD FLOW (CBF) INDEPENDENT OF ITS EFFECT ON MEAN ARTERIAL PRESSURE (MAP) IN DOGS

Anesthesia & Analgesia ◽

10.1097/00000539-199902001-00103 ◽

1999 ◽

Vol 88 (Supplement) ◽

pp. 103S

Author(s):

H. Sungurtekin ◽

U. Boston ◽

D.J. Cook

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Cardiopulmonary Bypass ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Pump Flow

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Faculty of 1000 evaluation for Pilot alternating treatment design study of the splanchnic metabolic effects of two mean arterial pressure targets during cardiopulmonary bypass.

F1000 - Post-publication peer review of the biomedical literature ◽

10.3410/f.717976182.793472206 ◽

2013 ◽

Author(s):

Andreas Hoeft

Keyword(s):

Cardiopulmonary Bypass ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Metabolic Effects ◽

Design Study ◽

Alternating Treatment Design ◽

Treatment Design

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The effect of mean arterial pressure during cardiopulmonary bypass on clinical and para clinical parameters during and after coronary artery bypass graft surgery

European Journal of Anaesthesiology ◽

10.1097/00003643-201206001-00227 ◽

2012 ◽

Vol 29 ◽

pp. 69-70

Author(s):

O. Aghadavoudi Jolfaei ◽

K. Bagheri ◽

O. Motamedi ◽

M. Akbari

Keyword(s):

Cardiopulmonary Bypass ◽

Coronary Artery ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Coronary Artery Bypass Graft ◽

Coronary Artery Bypass ◽

Artery Bypass ◽

Bypass Graft ◽

Clinical Parameters ◽

Artery Bypass Graft

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Sodium thiopental and mean arterial pressure during cardiopulmonary bypass

Asian Cardiovascular and Thoracic Annals ◽

10.1177/0218492311411316 ◽

2011 ◽

Vol 19 (3-4) ◽

pp. 213-216 ◽

Cited By ~ 4

Author(s):

Ali Dabbagh ◽

Samira Rajaei ◽

Mohammad Reza Ahani

Keyword(s):

Cardiopulmonary Bypass ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Sodium Thiopental

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Defining an Intraoperative Hypotension Threshold in Association with Stroke in Cardiac Surgery

Anesthesiology ◽

10.1097/aln.0000000000002298 ◽

2018 ◽

Vol 129 (3) ◽

pp. 440-447 ◽

Cited By ~ 63

Author(s):

Louise Y. Sun ◽

Amy M. Chung ◽

Michael E. Farkouh ◽

Sean van Diepen ◽

Jesse Weinberger ◽

...

Keyword(s):

Cardiac Surgery ◽

Cardiopulmonary Bypass ◽

Mean Arterial Pressure ◽

Arterial Pressure ◽

Odds Ratio ◽

Adjusted Odds Ratio ◽

Bypass Graft ◽

Perioperative Stroke ◽

Intraoperative Hypotension ◽

Tertiary Center

Abstract What We Already Know about This Topic What This Article Tells Us That Is New Background Stroke is a leading cause of morbidity, mortality, and disability in patients undergoing cardiac surgery. Identifying modifiable perioperative stroke risk factors may lead to improved patient outcomes. The association between the severity and duration of intraoperative hypotension and postoperative stroke in patients undergoing cardiac surgery was evaluated. Methods A retrospective cohort study was conducted of adult patients who underwent cardiac surgery requiring cardiopulmonary bypass at a tertiary center between November 1, 2009, and March 31, 2015. The primary outcome was postoperative ischemic stroke. Intraoperative hypotension was defined as the number of minutes spent within mean arterial pressure bands of less than 55, 55 to 64, and 65 to 74 mmHg before, during, and after cardiopulmonary bypass. The association between stroke and hypotension was examined by using logistic regression with propensity score adjustment. Results Among the 7,457 patients included in this analysis, 111 (1.5%) had a confirmed postoperative diagnosis of stroke. Stroke was strongly associated with sustained mean arterial pressure of less than 64 mmHg during cardiopulmonary bypass (adjusted odds ratio 1.13; 95% CI, 1.05 to 1.21 for every 10 min of mean arterial pressure between 55 and 64 mmHg; adjusted odds ratio 1.16; 95% CI, 1.08 to 1.23 for every 10 min of mean arterial pressure less than 55 mmHg). Other factors that were independently associated with stroke were older age, hypertension, combined coronary artery bypass graft/valve surgery, emergent operative status, prolonged cardiopulmonary bypass duration, and postoperative new-onset atrial fibrillation. Conclusions Hypotension is a potentially modifiable risk factor for perioperative stroke. The study’s findings suggest that mean arterial pressure may be an important intraoperative therapeutic hemodynamic target to reduce the incidence of stroke in patients undergoing cardiopulmonary bypass.

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