title: Are children undergoing cardiac surgery receiving antibiotics at subtherapeutic levels?
abstract: OBJECTIVE
  Perioperative antibiotics have decreased-but not eradicated-postoperative infections. In patients undergoing cardiac surgery with cardiopulmonary bypass, the dilutional effect of the priming and any additional volume given during the procedure may lead to subtherapeutic antibiotic levels. Our aim was to determine if children undergoing cardiac surgery with cardiopulmonary bypass receive perioperative antibiotics at subtherapeutic levels.
  
  
  METHODS
  Using published pharmacokinetic data on cefuroxime, we developed a computer simulation model to generate a nomogram predicting patients at risk for subtherapeutic cefuroxime levels based on time from initial dosing and additional volume given.
  
  
  RESULTS
  A computer-generated 1-compartment pharmacokinetic model was created to predict cefuroxime plasma levels over time for patients of all weights and additional volumes given for both a 25- and 50-mg/kg intravenous dose. For example, following a 25-mg/kg dose, a patient receiving an additional volume of 275 mL/kg is predicted to be subtherapeutic (<16 mg/L=4×minimum inhibitory concentration) at 4 hours. Our nomogram predicts all patients will be subtherapeutic at 8 hours, consistent with general pediatrics dosing schemes. Following a 50-mg/kg dose, levels are predicted to be subtherapeutic after an additional volume of 315 mL/kg at 5.5 hours.
  
  
  CONCLUSIONS
  Our model predicts which patients undergoing cardiac surgery with cardiopulmonary will have subtherapeutic cefuroxime levels. This nomogram enables providers to determine when to administer additional antibiotics in patients receiving large additional volumes during cardiac surgeries. This rational approach to perioperative antibiotic dosing may result in a reduction in postoperative infection in this vulnerable patient population.
authors: Division of Pediatric Cardiology, Doernbecher Children's Hospital, Oregon Health Science University, Portland, Ore. Electronic address: huangje@ohsu.edu.
authors: Jennifer H
authors: JH
authors: Huang
authors: Division of Pediatric Cardiac Surgery, Oregon Health Science University, Doernbecher Children's Hospital, Portland, Ore.
authors: Rachel
authors: R
authors: Sunstrom
authors: College of Pharmacy, Oregon State University, Corvallis, Ore.
authors: Myrna Y
authors: MY
authors: Munar
authors: College of Pharmacy, Oregon State University, Corvallis, Ore.
authors: Ganesh
authors: G
authors: Cherala
authors: Division of Pediatric Cardiology, Doernbecher Children's Hospital, Oregon Health Science University, Portland, Ore.
authors: Arthur
authors: A
authors: Legg
authors: College of Pharmacy, Oregon State University, Corvallis, Ore.
authors: Ali J
authors: AJ
authors: Olyeai
authors: Division of Pediatric Cardiac Surgery, Oregon Health Science University, Doernbecher Children's Hospital, Portland, Ore.
authors: Stephen M
authors: SM
authors: Langley
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D006348:Cardiac Surgical Procedures; D002444:Cefuroxime / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D002675:Child, Preschool; D003198:Computer Simulation; D006801:Humans; D007223:Infant; D011237:Predictive Value of Tests
chemical_list: D000900:Anti-Bacterial Agents; D002444:Cefuroxime