Modification of intravenous lidocaine-induced convulsions by epinephrine in rats.
We studied intravenous lidocaine-induced convulsions in rats to determine whether added epinephrine influences the provocation of lidocaine toxicity. Wistar rats (200-250 g) were divided into three groups of ten, depending on the concentration of epinephrine added to lidocaine. Group 1: plain 1.5% lidocaine; Group 2: 1.5% lidocaine with 1:200,000 epinephrine; Group 3: 1.5% lidocaine with 1:100,000 epinephrine. After surgical preparation and recovery from anaesthesia, all rats received a continuous i.v. infusion of lidocaine (15 mg.ml-1) at a rate of 4.0 mg.kg-1 x min-1 until generalized convulsions occurred. The epinephrine-treated animals developed acute hypertension after one minute of lidocaine infusion (105 +/- 2 to 141 +/- 2 mmHg in Group 2 and 103 +/- 2 to 151 +/- 2 mmHg in Group 3). The PaO2 values in the epinephrine groups at the onset of convulsions were decreased significantly (88.3 +/- 1.0 to 84.0 +/- 1.5 mmHg in Group 2 P < 0.05 and 86.9 +/- 1.2 to 78.1 +/- 2.4 mmHg in Group 3 P < 0.01). However, these values were still within physiological ranges. Serum potassium concentrations in all groups were decreased P < 0.05, (4.24 +/- 0.09 to 3.52 +/- 0.12 mEq.L-1 in Group 1, 4.02 +/- 0.09 to 3.63 +/- 0.17 mEq.L-1 in Group 2, and 4.15 +/- 0.10 to 3.69 +/- 0.17 mEq.L-1 in Group 3).(ABSTRACT TRUNCATED AT 250 WORDS)
Yokoyama
M
M
Department of Anesthesiology, University of Kansas Medical Center, Kansas City 66160-7415.
Goto
H
H
Ueda
W
W
Hirakawa
M
M
Arakawa
K
K
D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D001794:Blood Pressure / Q000187:drug effects; D001923:Brain Chemistry; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004837:Epinephrine / Q000008:administration & dosage / Q000494:pharmacology*; D006339:Heart Rate / Q000187:drug effects; D007260:Infusion Pumps; D007275:Injections, Intravenous; D008012:Lidocaine / Q000008:administration & dosage / Q000009:adverse effects* / Q000032:analysis / Q000097:blood; D008297:Male; D010100:Oxygen / Q000097:blood; D011188:Potassium / Q000097:blood; D051381:Rats; D017208:Rats, Wistar; D012640:Seizures / Q000097:blood / Q000139:chemically induced* / Q000503:physiopathology
D001786:Blood Glucose; D008012:Lidocaine; D011188:Potassium; D010100:Oxygen; D004837:Epinephrine