The impact of temperature and pump flow rate during selective cerebral perfusion on regional blood flow in piglets

We conducted a prospective study to assess the impact of the blood pump flow rate (BFR) on the dialysis dose with a low dialysate flow rate. Seventeen patients were observed for 3 short hemodialysis sessions in which only the BFR was altered (300,350 and 450 mL/min). Kt/V urea increased from 0.54 ± 0.10 to 0.58 ± 0.08 and 0.61 ± 0.09 for BFR of 300, 400 and 450 mL/min. For the same BFR variations, the reduction ratio (RR) of β2microglobulin increased from 0.40 ± 0.07 to 0.45 ± 0.06 and 0.48 ± 0.06 and the RR phosphorus increased from 0.46 ± 0.1 to 0.48 ± 0.08 and 0.49 ± 0.07. In bivariate analysis accounting for repeated observations, an increasing BFR resulted in an increase in spKt/V (0.048 per 100 mL/min increment in BPR [p < 0.05, 95% CI (0.03–0.06)]) and an increase in the RR β2m (5% per 100 mL/min increment in BPR [p < 0.05, 95% CI (0.03–0.07)]). An increasing BFR with low dialysate improves the removal of urea and β2m but with a potentially limited clinical impact.

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A1107 CEREBRAL BLOOD FLOW AND METABOLISM ARE INDEPENDENT OF PUMP FLOW RATE DURING HYPOTHERMIC CARDIOPULMONARY BYPASS IN CHILDREN

Anesthesiology ◽

10.1097/00000542-199009001-01105 ◽

1990 ◽

Vol 73 (3A) ◽

pp. NA-NA

Author(s):

F H Kem ◽

W J Greeley ◽

R M Ungerleider ◽

T J Quill ◽

B. Baldwin ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Cardiopulmonary Bypass ◽

Flow Rate ◽

Hypothermic Cardiopulmonary Bypass ◽

Pump Flow ◽

Pump Flow Rate

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The effect of normothermic cardiopulmonary bypass on hepatic blood flow in the dog

Perfusion ◽

10.1177/026765918600100403 ◽

1986 ◽

Vol 1 (4) ◽

pp. 245-253 ◽

Cited By ~ 25

Author(s):

RT Mathie ◽

JB Desai ◽

KM Taylor

Keyword(s):

Blood Flow ◽

Cardiopulmonary Bypass ◽

Vascular Resistance ◽

Flow Rate ◽

Hepatic Blood Flow ◽

Liver Blood Flow ◽

Relative Reduction ◽

Blood Flows ◽

Pump Flow ◽

Pump Flow Rate

Hepatic blood flow was investigated in two groups of eight anaesthetized dogs during and after one hour of either pulsatile or non-pulsatile cardiopulmonary bypass (CPB). Mean perfusion pressure was maintained at 60 mmHg. Hepatic arterial (HA) and portal venous (PV) blood flows were measured using electromagnetic flow probes, and hepatic O 2 consumption determined. The results demonstrate that: (a) pulsatile CPB reduces peripheral vascular resistance during and after perfusion, and more effectively preserves pump flow rate and cardiac output than non-pulsatile CPB; (b) total liver blood flow is sustained more effectively by pulsatile CPB than by non-pulsatile CPB due to relative preservation of both HA and PV flows; (c) hepatic O2 consumption is only marginally better preserved during and after pulsatile CPB than with non-pulsatile perfusion. We conclude that: (a) pulsatile CPB tends to maintain hepatic blood flow through a relative reduction in HA vascular resistance and an improvement in PV flow produced passively by a greater pump flow rate; (b) pulsatile CPB less effectively benefits hepatic O2 consumption because of poor O2 uptake from the hepatic PV blood supply.

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Effect of pump flow rate on cerebral blood flow during hypothermic cardiopulmonary bypass in adults

Journal of Cardiothoracic and Vascular Anesthesia ◽

10.1016/s1053-0770(97)90047-1 ◽

1997 ◽

Vol 11 (4) ◽

pp. 415-419 ◽

Cited By ~ 27

Author(s):

David J. Cook ◽

Jacqueline A. Proper ◽

Thomas A. Orszulak ◽

Richard C. Daly ◽

William C. Oliver

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Cardiopulmonary Bypass ◽

Flow Rate ◽

Hypothermic Cardiopulmonary Bypass ◽

Pump Flow ◽

Pump Flow Rate

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Effect of altering pump flow rate on cerebral blood flow and metabolism in infants and children

The Annals of Thoracic Surgery ◽

10.1016/0003-4975(93)90683-9 ◽

1993 ◽

Vol 56 (6) ◽

pp. 1366-1372 ◽

Cited By ~ 37

Author(s):

Frank H. Kern ◽

Ross M. Ungerleider ◽

J.G. Reves ◽

Timothy Quill ◽

L.Richard Smith ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Flow Rate ◽

Infants And Children ◽

Pump Flow ◽

Pump Flow Rate ◽

In Infants And Children

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Chronic nonpulsatile blood flow. III. Effects of pump flow rate on oxygen transport and utilization in chronic nonpulsatile biventricular bypass

Journal of Thoracic and Cardiovascular Surgery ◽

10.1016/s0022-5223(96)70348-3 ◽

1996 ◽

Vol 111 (4) ◽

pp. 863-872 ◽

Cited By ~ 22

Author(s):

Ryuji Tominaga ◽

William Smith ◽

Alex Massiello ◽

Hiroaki Harasaki ◽

Leonard A.R. Golding

Keyword(s):

Blood Flow ◽

Flow Rate ◽

Oxygen Transport ◽

Pump Flow ◽

Pump Flow Rate

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Cardiac Bypass Pump Flow Management via NIRS Monitoring

Spectroscopy An International Journal ◽

10.1155/2003/693192 ◽

2003 ◽

Vol 17 (2-3) ◽

pp. 477-482

Author(s):

Andrew J. Macnab ◽

Roy E. Gagnon ◽

Faith A. Gagnon ◽

Derek Blackstock ◽

Jacques G. LeBlanc

Keyword(s):

Animal Model ◽

Blood Flow ◽

Flow Rate ◽

Blood Flow Rate ◽

Redox Status ◽

Status Change ◽

Flow Management ◽

Pump Flow ◽

Pump Flow Rate ◽

Cardiac Bypass

During cardiac surgery, bypass pumps rely on pressure monitors to evaluate flow. We studied whether it would be possible to optimize pump flow by monitoring changes in cerebral cytochromea,a3using NIRS to maintain cyt redox status at its pre-bypass level.Method: 18 healthy 7–45 kg swine were placed on bypass for repeated cycles of cooling and re-warming from 36 to 15 to 36°C in 3°C steps. Between each cycle, the swine's bypass pump blood flow rate was adjusted to restore cytochrome redox status to its pre-bypass value.Results: In all swine trials, the number of pump flow alterations imposed by NIRS monitoring ranged from 0 to 42, the average being 14 per trial. The best trial had 22 pump flow adjustments during which the range of cytochrome redox status change was 0.50±0.06μmol l–1. The average trial had a range of cytochrome redox status change of 1.50±0.22μmol l–1.Conclusion: NIRS-driven alterations in pump flow rate to maintain pre-bypass cytochrome redox status can be achieved successfully in the animal model.

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