The Need for Pharmacokinetic Monitoring of Gentamicin Therapy in Critically III Neonates

Gentamicin dosing and pharmacokinetics in low birth weight infants.

“…If the kinetic parameters obtained later than one week of life when an enormous amount of insensible water loss ceases, a physiological diuretic phase is over, and distribution of body fluid is stabilized, were used, the prediction of steady-state serum concentrations in low birth weight infants would be improved or become more accurate as observed in children and adults. It seems impossible to predict the steady-state serum gentamicin concentrations in low birth weight infants, based on the parameters obtained during the oliguric phase because of the subsequent alteration in their apparent volume of distribution, although successful predictions of steady-state gentamicin concentrations have been reported (Edgren et al 1984; Kalenga et al 1984).…”

“…Several recent studies in preterm low birth weight infants have shown that a currently recommended gentamicin dosage for neonates in the first week of life, that is, an intravenous dose of 5 mg/kg/day divided into two doses (McCracken and Nelson 1977), would result in potentially toxic levels (Szefler et al 1980;Mulhall et al 1983 ; Husson et al 1984; Koren et al 1985). Although the toxic range of gentamicin in neonates has not been precisely defined, several reports suggest a new therapeutic range, such that trough concentrations should not exceed 2-3 ,u g/ ml and peak concentrations should maintain below 8-10 pg/ml (Taylor and Finn 1981; Rajchot et al 1984 ; Koren et al 1985 Kalenga et al 1984) have been recommended in an attempt to provide a maximum potential benefit with a minimum risk of possible toxicity associated with genteamicin therapy.…”