TY - JOUR
T1 - Higher bypass temperature correlates with increased white cell activation in the microcirculation
AU - Anttila, Vesa
AU - Hagino, Ikuo
AU - Zurakowski, David
AU - Lidov, Hart G.W.
AU - Jonas, Richard A.
AU - Allen, Bradley
AU - Chitwood, W. Randolph
AU - DeCampli, William
AU - Kron, Irving L.
PY - 2004/6
Y1 - 2004/6
N2 - Objective: Cardiopulmonary bypass induces a systemic inflammatory response, which in turn promotes a cascade of leukocyte and endothelial cell activity. We investigated whether differences in bypass temperature and flow rate affect endothelial cell and leukocyte adhesion in the cerebral microcirculation. Methods: Thirty-six piglets (13.0 ± 1.1 kg) had a cranial window placed over the parietal cortex to evaluate the microcirculation by means of intravital microscopy. Animals were cooled to a temperature of 15°C, 25°C, or 34°C on cardiopulmonary bypass with hematocrit levels of 20% or 30% by using pH-stat management, followed by 60 minutes of reduced flow (10, 25, or 50 mL · kg-1 · min-11). Rhodamine staining was used to observe adherent and rolling leukocytes in post-capillary venules. Results: Higher bypass temperature correlated with significantly more adherent and rolling leukocytes during the full 60 minutes of low-flow bypass (P < .05). Poisson regression revealed more adherent leukocytes at 34°C than at 15°C and at a flow rate of 10 mL · kg-1 · min-1 compared with a flow rate of 50 mL · kg-1 · min-1. There was an inverse correlation between flow rate and the number of adherent and rolling leukocytes at 30, 45, and 60 minutes of low-flow bypass (P < .05). Temperature was a multivariable predictor of histologic score, with greater neurologic damage found after bypass at 34°C (P < .01). Conclusions: Leukocyte activation in cerebral microcirculation is increased with higher temperature and lower flow rate, suggesting that these variables influence the inflammatory response during cardiopulmonary bypass.
AB - Objective: Cardiopulmonary bypass induces a systemic inflammatory response, which in turn promotes a cascade of leukocyte and endothelial cell activity. We investigated whether differences in bypass temperature and flow rate affect endothelial cell and leukocyte adhesion in the cerebral microcirculation. Methods: Thirty-six piglets (13.0 ± 1.1 kg) had a cranial window placed over the parietal cortex to evaluate the microcirculation by means of intravital microscopy. Animals were cooled to a temperature of 15°C, 25°C, or 34°C on cardiopulmonary bypass with hematocrit levels of 20% or 30% by using pH-stat management, followed by 60 minutes of reduced flow (10, 25, or 50 mL · kg-1 · min-11). Rhodamine staining was used to observe adherent and rolling leukocytes in post-capillary venules. Results: Higher bypass temperature correlated with significantly more adherent and rolling leukocytes during the full 60 minutes of low-flow bypass (P < .05). Poisson regression revealed more adherent leukocytes at 34°C than at 15°C and at a flow rate of 10 mL · kg-1 · min-1 compared with a flow rate of 50 mL · kg-1 · min-1. There was an inverse correlation between flow rate and the number of adherent and rolling leukocytes at 30, 45, and 60 minutes of low-flow bypass (P < .05). Temperature was a multivariable predictor of histologic score, with greater neurologic damage found after bypass at 34°C (P < .01). Conclusions: Leukocyte activation in cerebral microcirculation is increased with higher temperature and lower flow rate, suggesting that these variables influence the inflammatory response during cardiopulmonary bypass.
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U2 - 10.1016/j.jtcvs.2004.01.037
DO - 10.1016/j.jtcvs.2004.01.037
M3 - Article
C2 - 15173737
AN - SCOPUS:2642510797
SN - 0022-5223
VL - 127
SP - 1781
EP - 1788
JO - Journal of Thoracic and Cardiovascular Surgery
JF - Journal of Thoracic and Cardiovascular Surgery
IS - 6
ER -