Endotracheal lidocaine administration via an esophageal combitube

• Published in: The Journal of emergency medicine 2000-02, Vol.18 (2), p.153-157
• Main Authors: Palmer, Robert B, Mautz, Douglas S, Cox, Kathy, Kharasch, Evan D
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Anesthesia, General - methods; Anesthetics, Local - administration & dosage; Anesthetics, Local - pharmacokinetics; Biological and medical sciences; Biological Availability; Chromatography, Gas; Combitube; endotracheal; Equipment Design; esophageal; Female; General pharmacology; Humans; Intubation, Intratracheal - instrumentation; Intubation, Intratracheal - methods; lidocaine; Lidocaine - administration & dosage; Lidocaine - pharmacokinetics; Male; Medical sciences; Middle Aged; pharmacokinetics; Pharmacokinetics. Pharmacogenetics. Drug-receptor interactions; Pharmacology. Drug treatments; Reference Values; Time Factors
• ISSN: 0736-4679; 2352-5029
• DOI: 10.1016/S0736-4679(99)00186-9

The purpose of this study was to test the hypothesis that lidocaine is systemically absorbed after administration via a Combitube placed in the esophagus, and that therapeutically significant plasma lidocaine concentrations can be attained using this route with standard endotracheal doses (2.0 mg/kg). During general anesthesia, 27 elective surgical patients received 2.0 mg/kg lidocaine (diluted as necessary with 0.9% saline to a minimum total volume of 10 mL) via a Combitube (study group, n = 13) or an endotracheal tube (control group, n = 14). Venous blood samples were drawn for 3 h after lidocaine administration and plasma concentrations determined by gas chromatography using a nitrogen-phosphorus detector (NPD). Overall, average lidocaine concentrations were maximal after 5 min, reaching 0.8 ± 0.7 and 1.7 ± 0.7 μg/mL in the Combitube and endotracheal tube groups, respectively. Individual patient peak concentrations averaged 1.0 ± 0.7 and 2.2 ± 1.1 μg/mL in the same two groups, 19 ± 16 and 10 ± 15 min after lidocaine administration, respectively. No patients reported chest discomfort or dyspnea upon awakening, and no other side effects were noted. In support of the hypothesis, administration of lidocaine via an esophageal Combitube results in systemic drug uptake; however, at conventional endotracheal doses, plasma concentrations are subtherapeutic. It remains to be determined whether higher doses of lidocaine administered via an esophageal Combitube will result in therapeutic plasma concentrations.