Plasma Concentrations of Lidocaine (Lignocaine) after Cranial Subcutaneous Injection during Neurosurgical Operations

Abstract

After cranial subcutaneous injection of lidocaine 0.8-3.7 mg/kgS adrenaline (epinephrine) 1:200,000 in neurosurgical patients, fast drug absorption was found with peak plasma concentrations of0.6-1 pg/ml in 5-10 min. However, the concentrations remained above the lowest effective antiarrhythmic level 0f0.6 pg/ml for only about 10 min. In one patient, simultaneously administered intravenous lidocaine had an additive effect on those levels. Induced hypotension (sodium nitroprusside) during aneurysm operations decreased the arterial plasma level of lidocaine and was followed by a new peak after discontinuation. Thus the absorption ofa drug during induced hypotension from subcutaneous tissue is often erratic. Received 4 A g w t , accepted f o r publication I2 December I979Plasma concentrations of lidocaine have been measured after endotracheal, intercostal, subcutaneous vaginal, epidural, and subcutaneous abdominal administrations

Local Anesthesia in Hair Transplantation

“…Plasma levels of lidocaine of 0.6-1 mg/ml were found within 5-10 minutes of injection. 31 In another study, after scalp lacerations were infiltrated with up to 300 mg of lidocaine in a 58 kg person (ie, 5.25 mg/kg) lidocaine plasma levels were undetectable. 32 It was presumed that this was due to vasoconstriction in traumatized tissues.…”