Conditions: Pharyngitis
Keywords: lidocaine tetracaine tracheal intubation pharyngitis
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 100
Healthy volunteers: no

Brief summary:
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.

Detailed description:
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of the inflation medium, intra cuff pressure, duration from intubation to extubation and volume of the inflation medium withdrawn from the cuff was noted.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.

Arms:
arm 1: air was used to inflate the cuff. arm 2: Normal saline was used to inflate the cuff. arm 3: 2% lidocaine was used to inflate the cuff. arm 4: 1% tetracaine was used to inflate the cuff.

Interventions: intervention 1: 2% lidocaine intervention 2: placebo intervention 3: 1% tetracaine intervention 4: N.S
Intervention descriptions: intervention 1: lidocaine: 2%, injected into the cuff to seal the space between the trachea and the tube at minimal volume intervention 2: Air injected into the cuff to seal the space between the trachea and the tube at minimal volume intervention 3: tetracaine: 1%, injected into the cuff to seal the space between the trachea and the tube at minimal volume intervention 4: 0.9% Normal saline injected into the cuff to seal the space between the trachea and the tube at minimal volume

Protocol document: