BACKGROUND: Caudal administration of levobupivacaine (2.5 mg/kg) in children is used frequently in some hospitals. However, no reports of levobupivacaine concentrations have been published with this dosing scheme. We report the results of a study on the pharmacokinetics of levobupivacaine (2.5 mg/kg) after caudal administration in children younger than 3 yr. METHODS: Ten children, aged 1-36 mo and scheduled for subumbilical surgery were studied under sevoflurane anesthesia. After caudal injection of 0.25% levobupivacaine (2.5 mg/kg), serial venous blood samples were taken for 3 h to measure total plasma concentration levels of levobupivacaine. Median (range) levobupivacaine Cmax and Tmax measured were 1.48 (0.62-2.40) microg/mL and 37 (10-60) min. The highest individual Cmax was observed in a 1-mo-old infant 30 min after caudal block. CONCLUSIONS: The highest Cmax reached in this study was close to the toxic threshold of adult patients. Although no adverse events have been reported, care must be taken, especially in small infants, after caudal administration of levobupivacaine (2.5 mg/kg).
BACKGROUND: Caudal administration of levobupivacaine (2.5 mg/kg) in children is used frequently in some hospitals. However, no reports of levobupivacaine concentrations have been published with this dosing scheme. We report the results of a study on the pharmacokinetics of levobupivacaine (2.5 mg/kg) after caudal administration in children younger than 3 yr. METHODS: Ten children, aged 1-36 mo and scheduled for subumbilical surgery were studied under sevoflurane anesthesia. After caudal injection of 0.25% levobupivacaine (2.5 mg/kg), serial venous blood samples were taken for 3 h to measure total plasma concentration levels of levobupivacaine. Median (range) levobupivacaine Cmax and Tmax measured were 1.48 (0.62-2.40) microg/mL and 37 (10-60) min. The highest individual Cmax was observed in a 1-mo-old infant 30 min after caudal block. CONCLUSIONS: The highest Cmax reached in this study was close to the toxic threshold of adult patients. Although no adverse events have been reported, care must be taken, especially in small infants, after caudal administration of levobupivacaine (2.5 mg/kg).