Plasma Concentrations of Lidocaine (Lignocaine) After Cranial Subcutaneous Injection During Neurosurgical Operations

Abstract

After cranial subcutaneous injection of lidocaine 0.8-3.7 mg/kg+adrenaline (epinephrine) 1:200,000 in neurosurgical patients, fast drug absorption was found with peak plasma concentrations of 0.6-1 microgram/ml in 5-10 min. However, the concentrations remained above the lowest effective antiarrhythmic level of 0.6 microgram/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 of a drug during induced hypotension from subcutaneous tissue is often erratic.

Plasma lidocaine concentrations after local anesthesia of the groin for cardiac catheterization

“…This is the first study investigating lidocaine plasma levels during cardiac catheterization. In concert with previously published data, we observed serum levels peaking around 15 min after infiltration of the groin [8]. However, the main finding of this study is that patients with arterial and venous access exhibit higher plasma levels than patients with only one arterial sheath.…”

Local Anesthesia in Hair Transplantation

“…In one study, rapid absorption was noted after subcutaneous infiltration of the scalp with 0.8–3.7 mg/kg of lidocaine (with 1:200,000 epinephrine). 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 .…”