Suppression of cough during emergence from general anesthesia: laryngotracheal lidocaine through a modified endotracheal tube.
OBJECTIVE
To ascertain if coughing during emergence from general anesthesia can be suppressed with a modified endotracheal tube.


METHODS
Randomized, double-blind, controlled study.


METHODS
Operating rooms at a university hospital.


METHODS
46 adult ASA physical status I, II, and III patients requiring elective surgery.


METHODS
Patients underwent general anesthesia with the laryngotracheal instillation of topical anesthesia (LITA) endotracheal tube (ETT). Thirty minutes before anticipated extubation, one investigator administered, via the LITA tube injection port onto the laryngotracheal mucosa, one of the following according to randomized preselection: 2 mg/kg with 4% lidocaine (Group I; n = 15); 4 mL with saline (Group 2;n = 16); and nothing (Control; n = 15). At the completion of surgery, with the patient adequately anesthetized, the oropharynx was gently suctioned, and the isoflurane was then turned off. When the isoflurane end-tidal concentration was < or =0.2%, the neuromuscular block was reversed and the inspiratory oxygen concentration was increased to 100% while awaiting the return of spontaneous ventilation.


METHODS
An observer who was blinded to the study drug regimens judged the presence or absence of cough upon emergence, over a 1-minute period. The observer noted the responses to the following verbal commands, in this order: 1) "open your eyes", 2) "grip my hand", and 3) "lift your head". Coughing was defined as any evidence of irritation from having a tube in the trachea. Blood samples for plasma lidocaine levels were taken at the time of extubation from patients who received lidocaine (Group 1).


RESULTS
Seventy-five percent of patients were found to have complete cough suppression upon emergence, while Group 2 (saline) had 14% and Group 3 (the control) only had 13% suppression.


CONCLUSIONS
The technique of laryngotracheal topical lidocaine administered by the LITA tube can, in most cases, provide a smooth emergence from general anesthesia without coughing.
Diachun
C A
CA
Department of Anesthesia, Stanford University School of Medicine, Stanford, CA 94305-5640, USA. Carol_Diachun@urmc.rochester.edu
Tunink
B P
BP
Brock-Utne
J G
JG
D000768:Anesthesia, General / Q000009:adverse effects*; D000779:Anesthetics, Local / Q000008:administration & dosage*; D003371:Cough / Q000517:prevention & control*; D004311:Double-Blind Method; D006801:Humans; D007442:Intubation, Intratracheal / Q000295:instrumentation*; D007830:Larynx / Q000187:drug effects*; D008012:Lidocaine / Q000008:administration & dosage*; D014132:Trachea / Q000187:drug effects*
D000779:Anesthetics, Local; D008012:Lidocaine