Background and Goal of Study: 

Sore throat is one of the common complication after surgery under general anesthesia requiring tracheal intubation. However, the way to attenuate POST which is widely accepted single intervention, has not been existed. Smooth passage of tracheal tube through the pharynx may be useful to decrease POST. We presume that the combination of physical (thermal softened tube) and pharmacological (lidocaine jelly) intervention together for smooth passage is better than single intervention alone about reducing POST.

Materials and Methods: 

In this prospective, double-blind, single-center, randomized controlled trial, 144 patients aged 20 -70 years who were classified as ASA physical status I-III scheduled for laparoscopic surgery as an elective procedure, were enrolled. Computer-generated codes were used randomly group assignment. Group A, Room temperature ETT with saline; Group B, Room temperature ETT with lidocaine jelly; Group C, thermal softened ETT with saline; Group D, thermal softened ETT with lidocaine jelly. ETT used in Groups C and D was softened by warming at 40˚C.

By using direct question, the incidence of POST was collected. The degree of sore throat severity was measured using visual analogue scale (VAS). Any other postoperative complications and perioperative consumption of analgesic drugs were checked.

Results and Discussion:

The overall incidence of POST was different among four groups (P<0.05). Group D had signiﬁcantly lower overall incidence of POST compared with Groups A (54.3% vs. 79.4%, P=0.027), B (54.3% vs. 81.8%, P=0.015) and C (54.3% vs. 82.9%, P=0.01). But there was no signiﬁcant difference in the incidence and severity of POST at all time points. The incidence of hoarseness was similar among groups (P=0.715). And no dysphagia occurred. 

Conclusion(s):

In conclusion, the overall incidence of POST was significantly lower in the combination of thermal softened tube and lidocaine jelly intervention together than either conventional tube or lidocaine jelly alone for reducing overall incidence of POST. However, there were no differences in the other results such as incidence of POST at any time point, severity of sore throat, incidence of hoarseness and adverse effects.


06 / The effects of prewarmed endotracheal tubes and 2% lidocaine jelly on postoperative sore throat