Prospective Trial to Compare Direct and Indirect Laryngoscopy Using C-MAC PM® with Macintosh Blade and D-Blade® in a Simulated Difficult Airway

Table 3

Improvement of ETI.

	No BURP			BURP			No BURP → BURP
	DM→VM	DM→VD	VM→VD	DM→VM	DM→VD	VM→VD	DM→DM	DM→VM	VM→VM	VD→VD	DM→VD
No improvement	26	6	5	18	1	0	32	18	17	1	1
Improvement	6	26	13	7	28	15	0	14	1	4	31
p value	0.01	<0.001	<0.001	<0.001	<0.001	<0.001	0.433	<0.001	0.0657	0.111	<0.001
Description	Improvement: changing from direct to indirect laryngoscopy with a Macintosh blade without BURP	Improvement: changing from direct to indirect laryngoscopy and a Macintosh to D-Blade® without BURP	Improvement: changing from a Macintosh to D-Blade® in indirect laryngoscopy without BURP	Improvement: changing from direct to indirect laryngoscopy with a Macintosh blade with BURP	Improvement: changing from direct to indirect laryngoscopy and a Macintosh to D-Blade® with BURP	Improvement: changing from a Macintosh to D-Blade® in indirect laryngoscopy with BURP	No Improvement: using additional BURP when performing direct laryngoscopy with a Macintosh blade	Improvement: changing from direct to indirect laryngoscopy with a Macintosh blade with BURP	No Improvement: using additional BURP when performing indirect laryngoscopy with a Macintosh blade	No Improvement: using additional BURP when performing indirect laryngoscopy with D-Blade®	Improvement: changing from direct to indirect laryngoscopy and a Macintosh to D-Blade® with BURP

Since only changes based on Cormack-Lehane grades 3 and 4 were examined and not changes based on grades 2a, 2b, and 1, this table shows differently evaluated numbers of analyzed patients.
Data dichotomized into improvement or no improvement when changing technique or blade.
p value calculated using Fisher’s exact test. Level of significance p < .05.
Improvement = change from poor to good view.
No improvement = persistent poor view.
DM = direct laryngoscopy Macintosh blade.
VM = videolaryngoscopy Macintosh blade.
VD = videolaryngoscopy D-Blade.