Related Experiment Video
Updated: Jan 20, 2026

Endotracheal Intubation in Mice via Direct Laryngoscopy Using an Otoscope
Published on: April 5, 2014
Effect of Head Elevation to Different Heights in Laryngeal Exposure with Direct Laryngoscopy
Pragya Acharya1, Anil Shrestha1, Arjun Gurung1
1Department of Anaesthesia, TUTH, Maharajgunj, Kathmandu, Nepal.
Background:
The purpose of this study was to determine the optimal pillow height for the best laryngoscopic view in adult patients scheduled for elective surgery under general anaesthesia.
Methods:
150 adult patients undergoing surgery under general anaesthesia with endotracheal intubation with no features suggestive of difficult airway were enrolled for the study. After induction of anaesthesia the assessment of direct laryngoscopic views was done at head positions without a pillow and with non-compressible pillows of heights 5cm and 10cm.
Results:
The laryngoscopic view with the 5cm pillow was significantly superior to other head position (p<0.01). The incidence of difficult laryngoscopy (Cormack and Lehane grade III) was 32.7% without a pillow which improved to (Cormack and Lehane grade III) 4% with 10cm pillow and there were no cases of difficult laryngoscopy with 5cm pillow.
Conclusions:
The use of 5cm pillow in the 'sniffing' position obtains the best laryngoscopic view during direct laryngoscopy.
More Related Videos
Related Concept Videos
Freezing Point Depression and Boiling Point Elevation
The boiling point of a liquid is the temperature at which its vapor pressure is equal to ambient atmospheric pressure. Since the vapor pressure of a solution is lowered due to the presence of nonvolatile solutes, it stands to reason that the solution’s boiling point will subsequently be increased. Vapor pressure increases with temperature, and so a solution will require a higher temperature than will pure solvent to achieve any given vapor pressure, including one...
Elevation of Intermediate Points on Vertical Curves
Muscles that Move the Head
The bilateral sternocleidomastoid, or SCM, and the suprahyoid and infrahyoid muscles are significant head flexors. The SCM muscles originate at the sternum and clavicle and attach to the mastoid process of the temporal bone. The SCM contracts bilaterally to bend the head forward, whereas...
Arteries of the Head and Neck
The internal carotid arteries supply blood to the anterior portion of the cerebrum. They enter the...
Veins of Head and Neck
On the other hand, the vertebral veins, unlike their arterial counterparts, are not primarily responsible for brain drainage. Instead, they drain the cervical vertebrae, spinal cord, and some small...
Directing Effect of Substituents: meta-Directing Groups

