title: Microcirculatory perfusion is preserved during off-pump but not on-pump cardiac surgery.
abstract: OBJECTIVE
  This study investigated the perioperative course of microcirculatory perfusion in off-pump compared with on-pump surgery. Additionally, the impact of changes in systemic hemodynamics, hematocrit, and body temperature was studied.
  
  
  METHODS
  Prospective, nonrandomized, observational study.
  
  
  METHODS
  Tertiary university hospital.
  
  
  METHODS
  Patients undergoing coronary artery bypass grafting with (n = 13) or without (n = 13) use of cardiopulmonary bypass.
  
  
  METHODS
  Microcirculatory measurements were obtained at 5 time points ranging from induction of anesthesia to ICU admission.
  
  
  RESULTS
  Microcirculatory recordings were performed with sublingual sidestream dark field imaging. Despite a comparable reduction in intraoperative blood pressure between groups, the perfused vessel density decreased more than 20% after onset of extracorporeal circulation but remained stable in the off-pump group. The reduction in microvascular perfusion in the on-pump group was further paralleled by decreased hematocrit and temperature. Although postbypass hematocrit levels and body temperature were restored to similar levels as in the off-pump group, the median microvascular flow index remained reduced after bypass (2.4 [2.3-2.7]) compared with baseline (2.8 [2.7-2.9]; p = 0.021).
  
  
  CONCLUSIONS
  Microcirculatory perfusion remained unaltered throughout off-pump surgery. In contrast, microvascular perfusion declined after initiation of cardiopulmonary bypass and did not recover in the early postoperative phase.
authors.affiliation: Department of Anesthesiology, VU University Medical Center, Amsterdam, The Netherlands; Department of Cardio-Thoracic Surgery, VU University Medical Center, Amsterdam, The Netherlands; Department of Cardio-Thoracic Surgery, VU University Medical Center, Amsterdam, The Netherlands. Electronic address: n.koning@vumc.nl.
authors.forename: Nick J
authors.initials: NJ
authors.lastname: Koning
authors.affiliation: Department of Cardio-Thoracic Surgery, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Alexander B A
authors.initials: AB
authors.lastname: Vonk
authors.affiliation: Department of Anesthesiology, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Michael I
authors.initials: MI
authors.lastname: Meesters
authors.affiliation: Department of Cardio-Thoracic Surgery, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Thomas
authors.initials: T
authors.lastname: Oomens
authors.affiliation: Department of Cardio-Thoracic Surgery, VU University Medical Center, Amsterdam, The Netherlands; Laboratory for Physiology, Institute for Cardiovascular Research, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Melissa
authors.initials: M
authors.lastname: Verkaik
authors.affiliation: Department of Cardio-Thoracic Surgery, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Evert K
authors.initials: EK
authors.lastname: Jansen
authors.affiliation: Department of Cardio-Vascular Surgery LUNAM University, Université d'Angers, Angers, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Baufreton
authors.affiliation: Department of Anesthesiology, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Christa
authors.initials: C
authors.lastname: Boer
mesh_terms: D000368:Aged; D000758:Anesthesia; D001794:Blood Pressure / Q000502:physiology; D001831:Body Temperature; D002302:Cardiac Output / Q000502:physiology; D002316:Cardiotonic Agents / Q000627:therapeutic use; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D047549:Coronary Artery Bypass, Off-Pump / Q000009:adverse effects*; D003422:Critical Care; D004298:Dopamine / Q000627:therapeutic use; D005260:Female; D006400:Hematocrit; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D008833:Microcirculation / Q000502:physiology*; D008875:Middle Aged; D005996:Nitroglycerin / Q000627:therapeutic use; D010477:Perfusion; D059035:Perioperative Period; D011446:Prospective Studies; D014665:Vasodilator Agents / Q000627:therapeutic use
chemical_list: D002316:Cardiotonic Agents; D014665:Vasodilator Agents; D005996:Nitroglycerin; D004298:Dopamine
keywords: cardiopulmonary bypass; coronary artery bypass; microcirculation; off-pump cardiac surgery