Felicita Livia Saldanha, Ananth Srikrishna Somayaji, Radhesh Hegde


Aims :

The most important step for optimal visualisation of the larynx is proper positioning of the head and neck. The objective of this study was to compare the incidence of difficult laryngoscopy and variables of the Intubation Difficulty Scale (IDS) between the sniffing position (SP) and the further head elevation (HE) (neck flexion) during laryngoscopy.

Materials and Methods :

Eighty patients were included in this study and randomly distributed to SP group (n=40) or HE group (n=40). SP was attained by flexing the neck on the chest with an incompressible head ring and maximal head extension at the atlanto-occipital joint whereas in the “HE” group,1.5-inch cushion was placed under the head to cause further neck flexion. Difficult laryngoscopy was graded using Cormack Lehane Grading and ease of intubation was assessed using the Intubation Difficulty Scale (IDS).

Results :

Patients in the HE group required more than one attempt at intubation, use of ELM, use of alternate techniques, and use of increased force during laryngoscopy and had higher Cormack Lehane grades (III and IV) as compared to those in the SP group.

Conclusion :

Sniffing position is superior to further neck flexion, as assessed by CLG and IDS and may be used as the standard position for laryngoscopy.


sniffing position, further neck flexion, intubation difficulty score

Full Text:



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