Gentamicin trough levels using a simplified extended-interval dosing regimen in preterm and term newborns.
To evaluate a simplified gentamicin extended-interval dosing regimen in a large cohort of preterm and term newborns, we conducted a retrospective cohort study over a 4-year period. All inborn newborns who received gentamicin for the first episode of suspected or proven sepsis were eligible. Newborns received 4 mg/kg gentamicin intravenously 24-hourly, except for those at <28 weeks of gestation who received gentamicin 36-hourly. Trough levels were taken before the third dose and considered non-toxic if ≤2 μg/mL. Infants were analysed in gestational age subgroups: <28 weeks, 28-31 weeks, 32-35 weeks, 36-39 weeks and ≥40 weeks. Newborns who received indomethacin co-medication were analysed separately. Nine hundred ninety-three newborns, gestational age range 23(+2)-42(+1) weeks, birth weight range 397-5936 g, were included. The median (interquartile range (IQR)) gentamicin trough level for all newborns was 1.3 μg/mL (0.8-1.7). Ninety per cent of newborns had non-toxic trough levels. The incidence of trough levels >2 μg/mL was between 2.2 and 9.7 % in all subgroups except for infants born at 28-31 weeks of gestation, where 21.7 % of trough levels were >2 μg/mL. Indomethacin co-medication significantly increased the median gentamicin trough level in preterm infants at <32 weeks of gestation.


CONCLUSIONS
This study demonstrates that simplified gentamicin dosage regimens are feasible. Prospective evaluations are required to establish safety profiles.
Department of Paediatrics, Mercy Hospital for Women, 163 Studley Road, Melbourne, VIC, 3084, Australia, kaikonig@gmail.com.
Kai
K
König
Angelina
A
Lim
Anne
A
Miller
Suzanne
S
Saker
Katelyn J
KJ
Guy
Charles P
CP
Barfield
D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D005839:Gentamicins / Q000008:administration & dosage*; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D012189:Retrospective Studies; D018805:Sepsis / Q000188:drug therapy*; D047929:Term Birth
D000900:Anti-Bacterial Agents; D005839:Gentamicins