Role change by Laryngoscopist and Assistant for external laryngeal manipulation (ELM) and Intubation

Tracheal intubation is considered the gold standard in securing the airway in a variety of patient populations and operations. It is most commonly performed by using direct laryngoscopy technique.

External laryngeal manipulation is a simple maneuver that facilitates laryngeal visualization during laryngoscopy. It coordinates the operator’s right hand with what it is being simultaneously visualized, allowing fine tuning of the manipulation to maximize the laryngeal exposure.

ELM has been shown to improve laryngeal exposure and makes better intubating conditions. ELM used to be done by the intubating person to guide the assistant to the best way of doing it to maximize the laryngeal view.

This study will be designed to test the hypothesis that ELM done by the operator offers the best laryngeal view for intubation.

The aim of this study will be to examine the changes in laryngoscopic views after ELM done by the person doing laryngoscopy and ease of intubation done by the assistant.

Objective

Primary: to compare the laryngoscopic view between operator preformed ELM and assistant performed ELM.

Secondary objective: To assis the ease of intubation if intubation is done by assistant while operator is preforming ELM.

After getting ethical committee approval and CTRI registration, this study will be done on 200 patients of age 18 to 55 years, either sex, undergoing elective surgery under general anaesthesia with endotracheal intubation requiring ELM during laryngoscopy. Written & informed consent will be taken from all patients. Patients having difficult airway, obesity ASA grade III-IV pregnancy or require fiber-optic intubation will be excluded from the study.

Laryngoscopy will be done by experienced anaesthetists with curved Macintosh blades and a trained assistant will be available to assist. The operator will perform laryngoscopy and the assistant will do the ELM. Percentage of glottic opening scores and Cormack and Lehane scale will be recorded. Then the ELM will be done by operator and the assistant will perform intubation from right side of operator. Again the POGO score and CL grade will be noted. Percentage of glottic opening scores and Cormack and Lehane scale will be use as outcome measures for comparison between different views. A 3 point scale will be use to assis the ease of intubation.

POGO ranged from 0% to 100%. A POGO of 100% denotes full visualization of the larynx from the interarytenoid notch to the anterior commissure of the vocal cords and a POGO score of zero means none of the glottis opening is seen.

Cormack and Lehane scale consisted of four grades; Grade 1 full view of the glottis, Grade 2 partial view of the glottis or arytenoids, Grade 3 only epiglottis visible and Grade 4 neither glottis nor epiglottis visible.