title: Dexamethasone levels predict cortisol response after infant cardiopulmonary bypass.
abstract: OBJECTIVE
  We sought to evaluate whether there is variability in blood dexamethasone levels after a standard 1 mg/kg dose of dexamethasone administered before infant cardiopulmonary bypass. We hypothesized that postoperative dexamethasone drug levels are highly variable, and that the infant stress response is related inversely to the amount of dexamethasone measured in the blood.
  
  
  METHODS
  Thirty-two infants (age, ≤365 days) received 1 mg/kg of dexamethasone before cardiopulmonary bypass (CPB) initiation. Blood was analyzed for cortisol, adrenocorticotropin, and interleukin (IL)-6, IL-8, and IL-10 levels after anesthesia induction, after CPB, after intensive care unit (ICU) arrival, and 4, 8, 12, and 24 hours after surgery. Patients were grouped as high dexamethasone (≥15 μg/dL) or low dexamethasone (<15 μg/dL) based on their level at ICU arrival.
  
  
  RESULTS
  Dexamethasone levels varied significantly between the high (n = 22) and low (n = 10) dexamethasone groups throughout the entire postoperative course and were correlated highly with cortisol response. Patients with high dexamethasone levels had postoperative cortisol levels that were lower than their pre-CPB baseline cortisol levels. Cortisol levels remained low throughout the first 24 postoperative hours even after dexamethasone levels neared zero. There were no significant differences between groups in the duration of mechanical ventilation or ICU length of stay.
  
  
  CONCLUSIONS
  Dexamethasone levels are highly variable at ICU arrival, despite standardized 1 mg/kg dosing before CPB initiation.
authors.affiliation: Division of Pediatric Critical Care, Department of Pediatrics and Adolescent Medicine, Mayo Clinic, Rochester, Minn. Electronic address: Crow.sheri@mayo.edu.
authors.forename: Sheri S
authors.initials: SS
authors.lastname: Crow
authors.affiliation: Department of Anesthesiology, Mayo Clinic, Rochester, Minn.
authors.forename: William C
authors.initials: WC
authors.lastname: Oliver
authors.affiliation: Division of Cardiothoracic Surgery, Mayo Clinic, Rochester, Minn.
authors.forename: Jamie A
authors.initials: JA
authors.lastname: Kiefer
authors.affiliation: Department of Laboratory Medicine, Mayo Clinic, Rochester, Minn.
authors.forename: Melissa R
authors.initials: MR
authors.lastname: Snyder
authors.affiliation: Division of Cardiothoracic Surgery, Mayo Clinic, Rochester, Minn.
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Dearani
authors.affiliation: Division of Statistics, Mayo Clinic, Rochester, Minn.
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Li
authors.affiliation: Division of Cardiothoracic Surgery, Mayo Clinic, Rochester, Minn.
authors.forename: Harold M
authors.initials: HM
authors.lastname: Burkhart
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000097:blood; D015415:Biomarkers / Q000097:blood; D006348:Cardiac Surgical Procedures / Q000009:adverse effects; D002315:Cardiopulmonary Bypass / Q000009:adverse effects*; D003907:Dexamethasone / Q000097:blood* / Q000627:therapeutic use; D005260:Female; D005938:Glucocorticoids / Q000097:blood* / Q000627:therapeutic use; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D007223:Infant; D007231:Infant, Newborn; D015278:Intensive Care Units, Pediatric; D016753:Interleukin-10 / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D016209:Interleukin-8 / Q000097:blood; D008297:Male; D011183:Postoperative Complications / Q000097:blood / Q000517:prevention & control*; D011446:Prospective Studies; D013997:Time Factors
chemical_list: D015415:Biomarkers; C508606:CXCL8 protein, human; D005938:Glucocorticoids; C508609:IL10 protein, human; C508600:IL6 protein, human; D015850:Interleukin-6; D016209:Interleukin-8; D016753:Interleukin-10; D003907:Dexamethasone; D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone
keywords: 20; 41; 41.1; ACTH; CHD; CPB; HCT; ICU; IL; RACHES; Risk Adjustment for Congenital Heart Surgery; adrenocorticotropin; cardiopulmonary bypass; congenital heart disease; hematocrit; intensive care unit; interleukin