title: Glial fibrillary acidic protein plasma levels are correlated with degree of hypothermia during cardiopulmonary bypass in congenital heart disease surgery.
abstract: Improved congenital heart defect (CHD) operations have reduced operative mortality to 3%. The major concern is now long-term neurological outcomes. We measured plasma glial fibrillary acidic protein (GFAP), an early marker of brain injury, during different phases of cardiopulmonary bypass (CPB), to correlate the increase of GFAP to clinical parameters or specific operative phases.
  
  
  
  We performed a prospective, single-centre, observational study in children undergoing cardiac operations. We studied 69 children with CHD and biventricular heart physiology: 26 had tetralogy of Fallot; 17 transposition of the great arteries; and 26 ventricular/atrial septal defects with or without associated arch defects. GFAP levels were measured by ELISA at different stages of CPB. We recorded clinical and surgical parameters and applied multivariable and logistic regressions to assess which parameters were independent predictors of variations in plasma GFAP.
  
  
  
  GFAP increased during CPB and peaked at the end of rewarming. Multivariable regression showed degree of hypothermia as the only significant independent predictor of GFAP increase, adjusted for age, prematurity, type of CHD, cyanosis, aortic cross-clamp time, haemodilution, neurological risk time interval and rewarming rate. Temperature nadir and neurological risk time interval were significant independent predictors of a GFAP value  > 0.46 ng/ml.
  
  
  
  Hypothermia degree during CPB is correlated with GFAP plasma increase in children with biventricular heart defects undergoing surgical repair. Rewarming is the most critical CPB phase for GFAP increase. The implication of high plasma GFAP is still under evaluation. Follow-up studies are ongoing to assess the reliability of GFAP as a marker of brain injury and/or as a predictor of neurodevelopmental abnormalities.
authors.affiliation: Critical Care Biology and PCare Laboratories, Pediatric Research Institute "Citta' della Speranza", Padova, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Vedovelli
authors.affiliation: Pediatric Cardiovascular Surgery Unit, Padova University Hospital, "V. Gallucci" Center, Padova, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Padalino
authors.affiliation: Department of Women's and Children's Health, Padova University Hospital, Padova, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: D'Aronco
authors.affiliation: Pediatric Cardiovascular Surgery Unit, Padova University Hospital, "V. Gallucci" Center, Padova, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Stellin
authors.affiliation: Department of Medicine DIMED, Padova University Hospital, Anesthesia and Resuscitation Institute, Padova, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Ori
authors.affiliation: Department of Clinical Sciences, Division of Neonatology, Polytechnic University of Marche and Azienda Ospedaliero-Universitaria Ospedali Riuniti, Ancona, Italy.
authors.forename: Virgilio P
authors.initials: VP
authors.lastname: Carnielli
authors.affiliation: Critical Care Biology and PCare Laboratories, Pediatric Research Institute "Citta' della Speranza", Padova, Italy.
authors.forename: Manuela
authors.initials: M
authors.lastname: Simonato
authors.affiliation: Department of Clinical and Experimental Medical Sciences, University of Udine, Udine, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Cogo
mesh_terms: D015415:Biomarkers / Q000097:blood; D001831:Body Temperature; D001930:Brain Injuries / Q000097:blood* / Q000209:etiology / Q000517:prevention & control; D002315:Cardiopulmonary Bypass / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D005904:Glial Fibrillary Acidic Protein / Q000097:blood*; D006330:Heart Defects, Congenital / Q000097:blood / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D007035:Hypothermia / Q000097:blood* / Q000150:complications / Q000175:diagnosis; D007036:Hypothermia, Induced / Q000009:adverse effects / Q000379:methods*; D007223:Infant; D008297:Male; D011446:Prospective Studies; D015203:Reproducibility of Results; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; D005904:Glial Fibrillary Acidic Protein
keywords: Biomarkers; Brain injury; Congenital heart disease; GFAP; Paediatrics; White matter