title: Multivariable predictors of substantial blood loss in children undergoing craniosynostosis repair: implications for risk stratification.
abstract: BACKGROUND
  Operative treatment of craniosynostosis is associated with substantial blood loss, often requiring transfusion of packed red blood cells (PRBC) and coagulation products.
  
  
  OBJECTIVE
  The aim of this prospective study was to analyze thromboelastographic (TEG) parameters and platelet fibrinogen product to determine predictors of substantial blood loss, and the need for PRBC transfusion and coagulation products.
  
  
  METHODS
  With IRB approval, we enrolled 120 children undergoing craniosynostosis repair with a standardized anesthetic, fluid management, and TEG measurements at predefined times. Outcomes of interest were intraoperative blood loss, and need for PRBC transfusion and coagulation products. Multivariable logistic regression and receiver operating characteristic (ROC) curve analysis was applied to determine independent predictors of substantial blood loss and need for coagulation products.
  
  
  RESULTS
  One hundred and eighteen children were included in the analysis. Forty-four required PRBC transfusion (median 26 ml·kg(-1) ; IQR: 22-42) with median blood loss of 56 ml·kg(-1) (IQR: 43-83). Factors associated with the PRBC transfusion included type of surgery, duration of surgery, and three TEG parameters, α-angle, MA, and K-time (all P < 0.001). A predictive algorithm was developed by subgroup analysis of cranial vault reconstruction (CVR) patients for substantial intraoperative blood loss (defined as ≥60 ml·kg(-1) ) and need for coagulation products with ROC-derived cut-off values: platelet fibrinogen product, <343; α-angle, <62°; MA, <55 mm; K-time, >2.1 min. The best prognostic combination included at least two of these four predictors (sensitivity 89%, specificity 90%). Multivariable regression identified MA as the only independent predictor of coagulation product administration (P < 0.001) and ROC analysis identified MA <46 mm as the optimal cut-off (sensitivity 86%, specificity 94%).
  
  
  CONCLUSIONS
  Risk for substantial intraoperative blood loss can be assessed using TEG parameters and platelet fibrinogen product, whereas the need for coagulation products is strongly related to low MA. Patients susceptible to substantial blood loss can be risk stratified based on their TEG/platelet fibrinogen product profile.
authors: Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA.
authors: Petra M
authors: PM
authors: Meier
authors: Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA.
authors: David
authors: D
authors: Zurakowski
authors: Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA.
authors: Susan M
authors: SM
authors: Goobie
authors: Department of Neurosurgery, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA.
authors: Mark R
authors: MR
authors: Proctor
authors: Department of Plastic and Oral Surgery, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA.
authors: John G
authors: JG
authors: Meara
authors: Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA.
authors: Vanessa J
authors: VJ
authors: Young
authors: Department of Plastic Surgery, Children's National Medical Center, George Washington School of Medicine, Washington, DC, USA.
authors: Gary F
authors: GF
authors: Rogers
authors: Department of Anesthesiology, Perioperative and Pain Medicine, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA.
authors: James A
authors: JA
authors: DiNardo
mesh_terms: D016063:Blood Loss, Surgical / Q000706:statistics & numerical data*; D001803:Blood Transfusion / Q000706:statistics & numerical data*; D002675:Child, Preschool; D003398:Craniosynostoses; D005260:Female; D005340:Fibrinogen / Q000032:analysis*; D006801:Humans; D007223:Infant; D008297:Male; D011446:Prospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D013916:Thrombelastography / Q000379:methods*
chemical_list: D005340:Fibrinogen
keywords: blood component transfusion; craniosynostosis; hemorrhage; risk factors; thrombelastography