DOI: 10.17632/26j5zyrwnx.1
title: Sore throat following routine tracheal intubation with a single-use plastic laryngoscope blade versus a reusable metal laryngoscope blade: A multicenter, prospective, randomized, single-blind controlled study

description: Background
Sore throat occurs in 30% of patients following tracheal intubation using a reusable metal blade. We observed an increase in the frequency of sore throat of 10% after the implementation of the Heine single-use plastic blade in our operating rooms. Sore throats induced by plastic blades have not been investigated. We aimed to evaluate the frequency of sore throat induced by this plastic blade in comparison with the Heine reusable metal blade after tracheal intubation.
Methods
This was a multicenter, prospective, randomized, and single-blind controlled trial.
A total of 693 adult patients, without predictive criteria for difficult tracheal intubation, scheduled for surgery with tracheal intubation, performed using a plastic or reusable blade according to a 60 s step-limit tracheal intubation algorithm, were included. The primary endpoint was the frequency of sore throat without swallowing, 24 h after tracheal intubation. The first secondary endpoint was the incidence of unexpectedly difficult tracheal intubation (Intubation Difficulty Score  1). 
Results
The frequency of sore throat was not significantly higher in the plastic group, at 24 h: 81 (23.1%) vs. 61 (17.8%); difference, 5.3%; 95% Confidence Interval, – 0.8 - 11.2; P = 0.087; The frequency of unexpected difficult tracheal intubations was significantly higher in the plastic group: 194 (55.3%) vs. 146 (42.7%); difference, 12.6%; 95% Confidence Interval, 12.3 - 12.8; P = 0.0009.

CONLUSION
The protective tracheal intubation algorithm used may explain the low incidence of sore throat in the two groups and the absence of significant difference despite a higher frequency of unexpectedly difficult tracheal intubation related to poor laryngeal view. 

Highlights
•	The Heine single-use plastic laryngoscope blade induces infrequent sore throat.
•	Poor laryngoscopy should lead to a rapid switch to an alternative technique.
•	A 60 s step-limit tracheal intubation algorithm potentially avoids injuries.
•	A protective algorithm with laryngoscope plastic blades may reduce sore throat.
•	A protective tracheal intubation algorithm would deserve implementation in theaters at the time of video-assisted laryngoscopes.

The data show numerous columns:
- Patients history
- Randomization number
- Patient predictive criteria for difficult tracheal intubation
- Sore Throat intensity separating patients without sore throat VAS 0/100 (no pain) from patient presenting with sore throat (VAS > 0/100)
- Description of tracheal intubation performed by a nurse anesthesist or by an anesthesiologist: POGO - GAET score - Cormack-Lehane score - Intubation Difficulty (IDS) score - Tracheal intubation duration - Use of alternative techniques (angle-tip introducer, Aitraq, head repositioning).
- Use of morphine in postoperative period : no difference.
- The two groups are already sorted in Plastic blade group and Metal blade groupe. Then, the randomization numbers are not in the numerical order.