Evaluation of Vancomycin Loading Dose in Pediatric Patients
Background: In adult patients, a loading dose of vancomycin (VAN) has been shown to be safe and effective in improving the likelihood of attaining a desirable initial trough level (10-20 mg/L). Despite many years of experience, the appropriate PK/PD parameter to predict efficacy of VAN dosing in children is uncertain.
Methods: A retrospective analysis of VAN dosing, subsequent trough attainment, and demographic data was completed for pediatric inpatients > 3 months of age who received a VAN loading dose between 12/15/2012-4/1/2013 and had ≥ 1 recorded steady-state trough level. Only the first course of VAN for each patient was included in the analysis. Patients on VAN prior to admission or with renal dysfunction were excluded.
Results: 19 patients were identified for inclusion in the study. Figure 1 shows the dosing strategy and initial trough level for each patient. Initial VAN troughs were obtained after at least 3 maintenances doses in 58% (11/19) patients, and as late as before the 8th dose in 1 patient. All patients received only 1 loading dose. The median loading dose administered was 25 mg/kg (range: 18 – 27.8) with a median maintenance dose of 15 mg/kg every 6 hours. For the entire study population, the initial median trough concentration was 10.9 mg/L (range: <5 – 23.8). 52.5% (10/19) had trough concentrations between 10-20 mg/L and 36.8% (7/19) between 5-10 mg/L. Only 1 patient (5.3%) had an undetectable (<5 mg/L) trough concentration; however, the level was drawn ~45 minutes late. Additionally, 1 patient (5.3%) reported a supratherapeutic trough concentration of 23.8; however, no elevations in serum creatinine were noted. Of those who were initiated on a maintenance dose of 15 mg/kg/dose every 6 hours after the initial loading dose, the initial median trough concentration was 10.4 mg/L (range: <5 – 23.8). No cases of nephrotoxicity were reported.
Conclusion: Use of a loading dose was safe and resulted in achievement of goal initial median trough concentrations of 10 – 20 mg/L in this study population. This may suggest that more aggressive and standardized dosing strategies may benefit pediatric patients in achieving early target trough concentration on VAN therapy.
P. H. Bhagat,