OBJECTIVE: The authors hypothesized that cardiopulmonary bypass (CPB) (on-pump) is associated with more severe changes in the microcirculatory blood flow and tissue oxygenation as compared with off-pump coronary artery bypass surgery. DESIGN: An observational study. SETTING: A university hospital and teaching hospital. PARTICIPANTS: Patients undergoing on-pump (n = 24) or off-pump (n = 24) cardiac surgery. INTERVENTIONS: Microcirculatory measurements were performed before CPB and 10 minutes after the switch to CPB or before and during cardiac luxation in off-pump patients. MEASUREMENTS AND MAIN RESULTS: Sublingual microcirculatory perfusion was investigated using side-stream dark field imaging, and sublingual microcirculatory oxygenation was measured using reflectance spectrophotometry. Conversion to CPB resulted in an increase in cardiac output from 4.0 ± 0.2 to 4.8 ± 0.3 L/min (p < 0.01) and a 40% reduction in arterial hemoglobin concentration. Cardiopulmonary bypass was associated with an increase in venular blood velocity from 349 ± 201 μm/s to 563 ± 227 μm/s (p < 0.05), a reduction in functional capillary density of 43%, and an increase in hemoglobin oxygenation of the red blood cells in the remaining filled capillaries from 47.2% ± 6.1% to 59.7% ± 5.2% (p < 0.001). The decrease in cardiac output during cardiac luxation from 4.5 ± 1.7 to 1.8 ± 0.8 L/min (p < 0.01) without hemoglobin changes was associated with a complete halt of capillary blood flow and a reduction in maximum capillary blood velocity from 895 ± 209 to 396 ± 178 μm/s (p < 0.01). The functional capillary density remained unchanged, whereas the hemoglobin oxygenation declined from 64.2% ± 9.1% to 48.6% ± 8.7% (p < 0.01). CONCLUSIONS: On-pump and off-pump cardiac surgery are associated with distinct alterations in sublingual microcirculatory perfusion and hemoglobin oxygenation. Although on-pump surgery results in a fall out of capillaries resulting in decreased oxygen extraction, off-pump surgery results in a cessation of flow during luxation resulting in decreased convection of oxygen transport.
OBJECTIVE: The authors hypothesized that cardiopulmonary bypass (CPB) (on-pump) is associated with more severe changes in the microcirculatory blood flow and tissue oxygenation as compared with off-pump coronary artery bypass surgery. DESIGN: An observational study. SETTING: A university hospital and teaching hospital. PARTICIPANTS: Patients undergoing on-pump (n = 24) or off-pump (n = 24) cardiac surgery. INTERVENTIONS: Microcirculatory measurements were performed before CPB and 10 minutes after the switch to CPB or before and during cardiac luxation in off-pump patients. MEASUREMENTS AND MAIN RESULTS: Sublingual microcirculatory perfusion was investigated using side-stream dark field imaging, and sublingual microcirculatory oxygenation was measured using reflectance spectrophotometry. Conversion to CPB resulted in an increase in cardiac output from 4.0 ± 0.2 to 4.8 ± 0.3 L/min (p < 0.01) and a 40% reduction in arterial hemoglobin concentration. Cardiopulmonary bypass was associated with an increase in venular blood velocity from 349 ± 201 μm/s to 563 ± 227 μm/s (p < 0.05), a reduction in functional capillary density of 43%, and an increase in hemoglobin oxygenation of the red blood cells in the remaining filled capillaries from 47.2% ± 6.1% to 59.7% ± 5.2% (p < 0.001). The decrease in cardiac output during cardiac luxation from 4.5 ± 1.7 to 1.8 ± 0.8 L/min (p < 0.01) without hemoglobin changes was associated with a complete halt of capillary blood flow and a reduction in maximum capillary blood velocity from 895 ± 209 to 396 ± 178 μm/s (p < 0.01). The functional capillary density remained unchanged, whereas the hemoglobin oxygenation declined from 64.2% ± 9.1% to 48.6% ± 8.7% (p < 0.01). CONCLUSIONS: On-pump and off-pump cardiac surgery are associated with distinct alterations in sublingual microcirculatory perfusion and hemoglobin oxygenation. Although on-pump surgery results in a fall out of capillaries resulting in decreased oxygen extraction, off-pump surgery results in a cessation of flow during luxation resulting in decreased convection of oxygen transport.
Authors: John C Greenwood; David H Jang; Stephen D Hallisey; Jacob T Gutsche; Jiri Horak; Michael A Acker; Christian A Bermudez; Victoria L Zhou; Shampa Chatterjee; Frances S Shofer; Todd J Kilbaugh; John G T Augoustides; Nuala J Meyer; Jan Bakker; Benjamin S Abella Journal: J Cardiothorac Vasc Anesth Date: 2020-05-14 Impact factor: 2.628
Authors: Koray Yuruk; Rick Bezemer; Mariska Euser; Dan M J Milstein; Hilde H R de Geus; Evert W Scholten; Bas A J M de Mol; Can Ince Journal: Interact Cardiovasc Thorac Surg Date: 2012-06-14
Authors: Can Ince; E Christiaan Boerma; Maurizio Cecconi; Daniel De Backer; Nathan I Shapiro; Jacques Duranteau; Michael R Pinsky; Antonio Artigas; Jean-Louis Teboul; Irwin K M Reiss; Cesar Aldecoa; Sam D Hutchings; Abele Donati; Marco Maggiorini; Fabio S Taccone; Glenn Hernandez; Didier Payen; Dick Tibboel; Daniel S Martin; Alexander Zarbock; Xavier Monnet; Arnaldo Dubin; Jan Bakker; Jean-Louis Vincent; Thomas W L Scheeren Journal: Intensive Care Med Date: 2018-02-06 Impact factor: 17.440