Effect of Intra-cuff Lidocaine and Tetracaine on Tracheal Tube-induced Emergence Phenomena

It has been proven that tracheal tube inflated with lidocaine could decrease the post-intubation sore throat in nitrous oxide anesthesia. In the study, the investigators would like to evaluate the effect of lidocaine inflation in non-nitrous oxide anesthesia and compare the effect of tetracaine, the best mucosal local anesthetics with lidocaine.

The female patients receiving gynecological surgeries were divided into air, saline and 2% lidocaine and 1% tetracaine groups of 25 each using sealed envelope technique. The cuff of the endotracheal tube was inflated by the inflation medium (with the help of intracuff pressure monitoring device) to occlude the leak around the tube by the Minimal Occlusive Volume Technique. This was done by the same anaesthesiologist in all the patients. The cuff volume and pressure were then recorded. The primary outcome of the study was to evaluate the post-intubation sore throat using the visual analogue scale 6h, 24h and 48h after extubation. The secondary outcomes were incidence of complications during emergence of anesthesia and after extubation. Intra-cuff pressure monitoring was done with a pressure monitor, which consisted of the pressure gauge, three-way stopcock whose one end was attached to the pressure monitoring line. Net volume of the inflation medium was noted. Volume of the inflation medium, intra cuff pressure, duration from intubation to extubation and volume of the inflation medium withdrawn from the cuff was noted. Incidence (Yes/No) of tube intolerance, coughing on tube, restlessness, hoarseness, sore throat, breathlessness and laryngospasm were analyzed by the anaesthesiologist who did not know which group the patient belonged to.

lidocaine: 2%, injected into the cuff to seal the space between the trachea and the tube at minimal volume

tetracaine: 1%, injected into the cuff to seal the space between the trachea and the tube at minimal volume

0.9% Normal saline injected into the cuff to seal the space between the trachea and the tube at minimal volume

visual analogue scale (VAS) was used to evaluate the post-intubation sore throat. The VAS was a well-recongnized standard tool for rating of pain. The VAS measures exactly 100 mm. 0 means no pain and 100 means the worst pain that one can image. Patient marks a point on the line that matches the amount of pain he or she feels.

Inclusion Criteria: patients of the age group 18-60 years patients belonging to ASA grade I and II undergoing gynecological surgeries in supine position under general anesthesia with controlled ventilation using Poly Vinyl Chloride ETT (same type and make in all patients) Exclusion Criteria: anticipated difficult intubation more than one attempt for intubation need for naso gastric tube episode of coughing and straining history of respiratory tract infection and smoking

Estebe JP, Delahaye S, Le Corre P, Dollo G, Le Naoures A, Chevanne F, Ecoffey C. Alkalinization of intra-cuff lidocaine and use of gel lubrication protect against tracheal tube-induced emergence phenomena. Br J Anaesth. 2004 Mar;92(3):361-6. doi: 10.1093/bja/aeh078.