title: The Use of Epinephrine in Caudal Anesthesia Increases Stroke Volume and Cardiac Output in Children.
abstract: OBJECTIVE
  Caudal anesthesia is a common and effective regional anesthesia technique in pediatric patients. The addition of epinephrine to local anesthetics in caudal anesthesia is a frequent practice; however, changes in hemodynamic and cardiac parameters produced by epinephrine in caudal anesthesia are not well studied. Using data collected with the ICON noninvasive cardiac output monitor, we examined the hemodynamic changes associated with the administration of epinephrine containing local anesthetics during caudal anesthesia in children.
  
  
  METHODS
  We performed a retrospective analysis of 40 patients who received caudal anesthesia among 402 patients from whom we prospectively collected continuous noninvasive cardiac output data using the ICON monitor, which estimates cardiac output by measuring changes in thoracic bioimpedance during the cardiac cycle. Twenty-three children received epinephrine with local anesthetic (ELA), and 17 children received only local anesthetic (OLA) in their caudal blocks. We compared heart rate (HR), stroke volume (SV), cardiac output (CO), and cardiac index (CI) changes from baseline before caudal injection to 1-minute intervals over 15 minutes after caudal injection for both ELA and OLA groups (Table, Supplemental Digital Content 1, http://links.lww.com/AAP/A179). We also performed subgroup analysis of the same parameters comparing both ELA and OLA groups in infants younger than 6 months and in children 6 months or older.
  
  
  RESULTS
  Stroke volume, CO, and CI are significantly increased after caudal injection in the ELA group compared with baseline values at caudal injection time. Conversely, there were no statistically significant changes in SV, CO, and CI in the OLA group. There were no significant HR or blood pressure changes observed in either the ELA or OLA group within 15 minutes compared with baseline caudal injection time. In infants younger than 6 months, no significant differences were found in HR, SV, and CI in children in the ELA group compared with the OLA group. In children 6 months or older, SV and CI increased significantly in the ELA group compared with the OLA group.
  
  
  CONCLUSIONS
  Epinephrine added to local anesthetic injected for caudal anesthesia produces significant increases in SV, CO, and CI in children. Stroke volume and CI changes from epinephrine added to local anesthetic for caudal anesthesia seem to take place only in children 6 months or older.
authors.affiliation: From the Department of Anesthesiology, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA.
authors.forename: Chang Amber
authors.initials: CA
authors.lastname: Liu
authors.forename: Jinghu
authors.initials: J
authors.lastname: Sui
authors.forename: Charles J
authors.initials: CJ
authors.lastname: Coté
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Anderson
mesh_terms: D000316:Adrenergic alpha-Agonists / Q000494:pharmacology*; D000763:Anesthesia, Caudal; D000779:Anesthetics, Local; D002302:Cardiac Output / Q000187:drug effects*; D002648:Child; D002675:Child, Preschool; D004837:Epinephrine / Q000494:pharmacology*; D005260:Female; D006439:Hemodynamics; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D012189:Retrospective Studies; D013318:Stroke Volume / Q000187:drug effects*
chemical_list: D000316:Adrenergic alpha-Agonists; D000779:Anesthetics, Local; D004837:Epinephrine