title: Is selective antegrade cerebral perfusion superior to retrograde cerebral perfusion for brain protection during deep hypothermic circulatory arrest? Metabolic evidence from microdialysis.
abstract: OBJECTIVE
  This study aimed to investigate whether selective antegrade cerebral perfusion or retrograde cerebral perfusion is a better technique for brain protection in deep hypothermic circulatory arrest by obtaining metabolic evidence from microdialysis.
  
  
  METHODS
  Randomized, animal study.
  
  
  METHODS
  Assisted circulation laboratory.
  
  
  METHODS
  Eighteen piglets of either sex (9.8 ± 3.1 kg).
  
  
  METHODS
  Animals were randomly assigned to 40 minutes of circulatory arrest at 18°C without cerebral perfusion (deep hypothermic circulatory arrest group, n = 6) or with selective antegrade cerebral perfusion (selective antegrade cerebral perfusion group, n = 6) or retrograde cerebral perfusion (retrograde cerebral perfusion group, n = 6). Reperfusion was continued for 3 hours.
  
  
  RESULTS
  Microdialysis (glucose, lactate, pyruvate, and glycerol) variables in the cortex dialysate were measured every 30 minutes. Intracerebral pressure and serum S-100 levels were also monitored. After 3 hours of reperfusion, cortical tissue was harvested for terminal deoxynucleotidyl transferase dUTP nick-end labeling staining. After 40 minutes of circulatory arrest, the deep hypothermic circulatory arrest group presented marked elevations of intracerebral pressure, and serum S-100 levels were higher in the deep hypothermic circulatory arrest group than in the other two groups (p < 0.001, respectively). The selective antegrade cerebral perfusion group exhibited higher glucose, lower lactate, and lower glycerol levels and a lower lactate-to-pyruvate ratio in comparison to the deep hypothermic circulatory arrest group (p < 0.05, respectively); the retrograde cerebral perfusion group had lower lactate and glycerol levels and a lower lactate-to-pyruvate ratio (p < 0.05, respectively) but similar glucose levels compared to deep hypothermic circulatory arrest alone. Furthermore, selective antegrade cerebral perfusion provided better preservation of energy and cell integrity than retrograde cerebral perfusion with higher glucose and lower glycerol levels (p < 0.05, respectively). After 3 hours of reperfusion, fewer apoptotic neurons were found in selective antegrade cerebral perfusion animals than in the other two groups (p < 0.05, respectively).
  
  
  CONCLUSIONS
  Both selective antegrade cerebral perfusion and retrograde cerebral perfusion were superior to deep hypothermic circulatory arrest alone during circulatory arrest. Retrograde cerebral perfusion was a moderate technique that had similar advantages with regard to less cerebral edema, better clearance of metabolic waste, and lower levels of biomarkers of injury than selective antegrade cerebral perfusion, but its capacity for energy preservation, maintenance of cellular integrity, and protection against apoptosis was lower than that of selective antegrade cerebral perfusion.
authors.affiliation: 1Department of Cardiac Surgery, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China. 2Department of Anesthesiology, Heart Center, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China.
authors.forename: Meng-Ya
authors.initials: MY
authors.lastname: Liang
authors.forename: Zhi-Xian
authors.initials: ZX
authors.lastname: Tang
authors.forename: Guang-Xian
authors.initials: GX
authors.lastname: Chen
authors.forename: Jian
authors.initials: J
authors.lastname: Rong
authors.forename: Jian-Ping
authors.initials: JP
authors.lastname: Yao
authors.forename: Zhen
authors.initials: Z
authors.lastname: Chen
authors.forename: Zhong-Kai
authors.initials: ZK
authors.lastname: Wu
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001921:Brain / Q000378:metabolism* / Q000473:pathology; D001930:Brain Injuries / Q000517:prevention & control*; D050792:Circulatory Arrest, Deep Hypothermia Induced / Q000009:adverse effects / Q000379:methods*; D005947:Glucose / Q000032:analysis; D005990:Glycerol / Q000032:analysis; D020287:In Situ Nick-End Labeling; D019344:Lactic Acid / Q000032:analysis; D017551:Microdialysis / Q000379:methods*; D011773:Pyruvates / Q000032:analysis; D011897:Random Allocation; D015424:Reperfusion / Q000379:methods; D009418:S100 Proteins / Q000032:analysis*; D013552:Swine
chemical_list: D011773:Pyruvates; D009418:S100 Proteins; D019344:Lactic Acid; D005947:Glucose; D005990:Glycerol