title: Fibrin Network Changes in Neonates after Cardiopulmonary Bypass.
abstract: Quantitative and qualitative differences in the hemostatic systems exist between neonates and adults, including the presence of "fetal" fibrinogen, a qualitatively dysfunctional form of fibrinogen that exists until 1 yr of age. The consequences of "fetal" fibrinogen on clot structure in neonates, particularly in the context of surgery-associated bleeding, have not been well characterized. Here, the authors examine the sequential changes in clotting components and resultant clot structure in a small sample of neonates undergoing cardiac surgery and cardiopulmonary bypass (CPB).
  
  
  
  Blood samples were collected from neonates (n = 10) before surgery, immediately after CPB, and after the transfusion of cryoprecipitate (i.e., adult fibrinogen component). Clots were formed from patient samples or purified neonatal and adult fibrinogen. Clot structure was analyzed using confocal microscopy.
  
  
  
  Clots formed from plasma obtained after CPB and after transfusion were more porous than baseline clots. Analysis of clots formed from purified neonatal and adult fibrinogen demonstrated that at equivalent fibrinogen concentrations, neonatal clots lack three-dimensional structure, whereas adult clots were denser with significant three-dimensional structure. Clots formed from a combination of purified neonatal and adult fibrinogen were less homogenous than those formed from either purified adult or neonatal fibrinogen.
  
  
  
  The results of this study confirm that significant differences exist in clot structure between neonates and adults and that neonatal and adult fibrinogen may not integrate well. These findings suggest that differential treatment strategies for neonates should be pursued to reduce the demonstrated morbidity of blood product transfusion.
authors.affiliation: From the Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina at Chapel Hill, Raleigh, North Carolina (A.C.B.); The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia (R.H., L.H.T., T.H.B.); Division of Cardiology, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia (L.H.T.); and Department of Anesthesiology, Emory University School of Medicine, Children's Healthcare of Atlanta at Egleston, Atlanta, Georgia (J.D.F., N.A.G.).
authors.forename: Ashley C
authors.initials: AC
authors.lastname: Brown
authors.forename: Riley T
authors.initials: RT
authors.lastname: Hannan
authors.forename: Lucas H
authors.initials: LH
authors.lastname: Timmins
authors.forename: Janet D
authors.initials: JD
authors.lastname: Fernandez
authors.forename: Thomas H
authors.initials: TH
authors.lastname: Barker
authors.forename: Nina A
authors.initials: NA
authors.lastname: Guzzetta
mesh_terms: D000328:Adult; D001777:Blood Coagulation; D016063:Blood Loss, Surgical; D001803:Blood Transfusion; D002315:Cardiopulmonary Bypass / Q000009:adverse effects*; D005176:Factor XIII / Q000032:analysis; D005260:Female; D005337:Fibrin; D005340:Fibrinogen / Q000378:metabolism; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D018613:Microscopy, Confocal; D011516:Prothrombin / Q000032:analysis
chemical_list: D011516:Prothrombin; D005337:Fibrin; D005340:Fibrinogen; D005176:Factor XIII