Carbon Dioxide Insufflation in Routine Colonoscopy Is Safe and More Comfortable: Results of a Randomized Controlled Double-Blinded Trial

Table 2

Parameters of colonoscopy in CO₂ and room air group.

	CO2 group	Room air group	𝑃 value
Propofol	134 mg ± 56	120 mg ± 120	.9
Nasal oxygen substitution; if O2 saturation <90%	10%	20.2%	.02
Ileum intubation rate	95.5%^1	97.2% ^1	.22
Time to ileum	7.7±4.7 min	6.7±4.1 min	.18
Withdrawal time	13.6±6.0 min	13.3±6.1 min	.99
Intervention time	3.3±4.5 min	3.2±4.6 min	.99
Polyps	68.2%	68.8%	.11
>1 cm	8.2%	7.3%
0.5–1 cm	17.3%	16.6%
<0.5 cm	63.6%	66.1%
Findings			.77
Carcinoma	0.9%	1.8%
Relevant polyp^2	10.9%	7.3%
Small adenoma^3	34.5%	33.9%
Hyperplastic	13.6%	14.7%
CO2 (mmHg)
at start	33.4±4.7	34.6±5.1	.59
at ileum	37.3±5.2	37.0±5.2	.62
end of examination	35.2±4.3	35.6±6.0	.01
Maximal CO2 rise	4.2±3.7	2.9±4.4	.77

¹0.9% stenosis (e.g., tumor, or sigmoid stenosis due to diverticulosis) in both groups, reaching coecum in 99% in both groups.
²Relevant polyps defined as polyp >1 cm, serrated, and villous ± high-grade dysplasia.
³Polyps size <1 cm.