Comparative Evaluation of the Sniffing Position with Simple Head Extension for Laryngoscopic View and Intubation Difficulty in Adults Undergoing Elective Surgery

Table 5

Variables of the intubation difficulty scale.

	Sniffing position	Simple extension	𝑃 value
	(𝑛=275)	(𝑛=271)
Attempts > 1	20 (7.3)	34 (12.5)	0.010
Operators > 1	0 (0)	0 (0)	—
Cormack grade > 1	104 (37.8)	126 (46.5)	0.610
Increased lifting force	16 (5.8)	35 (12.9)	0.004
ELM	90 (32.7)	118 (43.5)	0.009
Alternative techniques	13 (4.7)	26 (9.6)	0.027
Vocal cords adducted	0 (0)	0 (0)	—

ELM: External laryngeal manipulation. Values are numbers (percent).