What is the maximum dose/kg of lidocaine in injection form for children?

Fråga: What is the maximum dose/kg of lidocaine in injection form for children?

Sammanfattning: The maximum dose of lidocaine as a local anaesthetic in children is 3 mg/kg without adrenaline and 7 mg/kg with adrenaline according to a textbook. However, the original studies were not available. The maximum dose may differ with anaesthesia in different locations.

Svar: Lidocaine as a local anaesthetic drug is introduced as close as possible to the nerves to be blocked in accordance with the relevant anatomy and clinical response. The maximum dose for children should not exceed 3 mg/kg without adrenaline and 7 mg/kg with adrenaline (1).

The manufacturer of lidocaine has been contacted and no further information has been provided. The maximum dose in children was not given in FASS since it may differ with different indications and in different locations.

One study on the safety of continuous pleural lidocaine after thoracotomy to provide postoperative analgesia in 96 patients aged from 5 months to 24 years has shown that pleural lidocaine infusions in the dosage of 20-40 ug/kg/min is safe. Seven of the patients had serum lidocaine concentrations greater than 5.0 ug/ml, but less than 8 ug/ml, and none of them manifested signs of toxicity (2).

According to a previous Drugline document on topical lidocaine usage in children, side effects and toxic effects are not seldom seen at plasma lidocaine concentrations above 5-6 ug/ml (3).