Cefuroxime Pharmacokinetics in Pediatric Cardiovascular Surgery Patients Undergoing Cardiopulmonary Bypass

Objectives The objective of this study was to determine the pharmacokinetics of cefuroxime in children undergoing cardiopulmonary bypass (CPB) for cardiovascular surgery. Design A prospective study. Setting A tertiary pediatric teaching hospital. Participants Infants and children undergoing CPB were enrolled in the study. Intervention An initial dose (mean, 24.2 ± 1.6 mg/kg) of cefuroxime was administered before surgical incision, and a second dose (mean, 14.4 ± 7.9 mg/kg) was administered in the CPB prime solution. Serial blood samples were obtained before, during, and after the CPB process. Samples were shipped on dry ice to the analytic laboratory and concentrations determined by a validated high-performance liquid chromatography method. A 2-compartment pharmacokinetic model was fitted to the data using maximum a priori–Bayesian estimation, with weight as a covariate. Monte Carlo simulations of a single-dose (25 mg/kg pre-CPB) approach and a 2-dose (25 mg/kg pre- and 12.5-mg/kg prime solution dose) approach were performed. Measurements and Main Results Fifteen subjects (9 males/6 females) were enrolled in the study, with median (range) age and weight of 11 (3-34) months and 9.5 (4.5-15.4) kg, respectively. The median (range) duration of CPB was 136 (71-243) minutes. Median and range cefuroxime pharmacokinetic parameters were as follows: maximum concentration (Cmax) dose, 1: 328 (150-512) μg/mL; systemic clearance, 0.050 (0.041-0.058) L/h/kg; steady-state volume of distribution, 0.213 (0.081-0.423) L/kg; volume of distribution in the central compartment, 0.081 (0.046-0.162) L/kg; and elimination half-life, 3.76 (1.03-6.81) hours. The median 8-hour post–dose-simulated cefuroxime concentrations were 26.5 and 16.0 mg/L for the 2-dose and single-dose regimens, respectively. Conclusion Manufacturers recommend that pediatric doses of cefuroxime (25-50 mg/kg) can be used in infants and children undergoing CPB to maintain adequate serum concentrations for surgical-site infection prophylaxis. A second intraoperative dose, administered through the CPB circuit, provides no additional prophylactic advantage

Commercial Very Low Energy Meal Replacements for Preoperative Weight Loss in Obese Patients: a Systematic Review

Background: This systematic review assessed feasibility and effectiveness of preoperative meal replacements to improve surgical outcomes for obese patients. Methods: PRISMA guidelines were followed and electronic databases searched for articles between January 1990 and March 2015. Results: Fifteen studies (942 participants including 351 controls) were included, 13 studies (n = 750) in bariatric patients. Adverse effects and dropout rates were minimal. Ten out of 14 studies achieved 5–10 % total weight loss. Six of six studies reporting liver volume achieved 10 % reduction. Endpoints for perioperative risks and outcomes were too varied to support definitive risk benefit. Conclusions: Commercial meal replacements are feasible, have minimal side effects and facilitate weight loss and liver shrinkage in free-living obese patients awaiting elective surgery. A reduction in surgical risk is unclear.Griffith Health, School of Allied Health SciencesNo Full Tex